"structure" 1. "what exactly is a structure? can you give examples? what other words...
TRANSCRIPT
Structure1 What exactly IS a ldquostructurerdquo Can you give examples What other words come
to mind
2List questions you want answered today
3 Then add your Post itregs to designated papers on wall
Welcome to an IncreDIble Illinois
Structure WorkshopStructure WorkshopPlease check in 1230- 100 pm
Brainstorming One idea per Post itreg
What is a Structure
bull A structure is anything made up of a number of parts that are held together in a particular way and has a base or foundation
bull All structures give support or provide a framework You can find structures everywhere Bridges buildings chairs shoes plants spider webs tables and even your own body are all structures A structures shape size and what its made of depend on what the structure does and how strong it needs to be
bull Form and FunctionEvery structure has form and function Form and Function are interconnected
The shape (or form) of something affects its purpose (or function)
Something with a certain shape can have more than one purpose or function
bull Forces of Tension and CompressionEvery structure is affected by forces
The force of one structure can affect another
The affect can go back and forth with a push and pull force
Compression and Tension are examples of push and pull forces
Compression the state of a material pressed together or forced into less space
Tension a stress on a material made by the pull of forces extending outwards
Structures in the Real World
You can find inspiration all around you if you just lookYou can find inspiration all around you if you just look
6 Flags ndash Texas Giant6 Flags ndash Texas Giant
6 Flags ndash G Force6 Flags ndash G Force
6 Flags ndash Bob Sled6 Flags ndash Bob Sled
6 Flags ndash Judge Roy Scream Roller Coaster6 Flags ndash Judge Roy Scream Roller Coaster
Construction Project ndash Masonry ScaffoldingConstruction Project ndash Masonry Scaffolding
DFW Airport ndash Tower Cranes used constructing new TerminalDFW Airport ndash Tower Cranes used constructing new Terminal
Six Flags ndash The TitanSix Flags ndash The Titan
DFW Airport ndash Doppler RadarDFW Airport ndash Doppler Radar
Six Flags ndash Mister FreezeSix Flags ndash Mister Freeze
Electrical Wire Transmission TowerElectrical Wire Transmission Tower
Six Flags Oil DerrickSix Flags Oil Derrick
DFW Airport - Scaffolding holding up concrete formsDFW Airport - Scaffolding holding up concrete forms
BasicConcepts
ampDefinitions
Intro to teaching basic structure
bull Wood
bull Jigs
bull Forces
bull Glue
bull Tools and More Tools
bull Construction Area
bull This yearrsquos Challenge
bull The Duct Tape Challenge
bull Summary
Construction Area
A large open table where team can place building jigs weigh wood saw and cut materials assemble amp finish structures
Cover the table top (sheet of thick plastic or masonite)Make sure that work areas are kept well ventilated especially when teams are using glues with harmful vapors
Cutting Tools and EquipmentCutting Tools and Equipment
Helping teams learnabout wood characteristics
bull Wood
ndash Wood comes in a variety of dimensions (sticks and planks)
ndash Hobby stores carry balsa and basswood (basswood generally denser and heavier)
ndash USA Balsa and SIG has a large assortment of wood (wwwsigmfgcom) ndash Factors to consider
bull Weightbull Strengthbull Ease of use
Wood Hands on
bull Examine the wood forndash Texturendash Grainndash Smoothnessndash Kerf marks
bull How porous is itbull How easy does a stick bendbull How much does it weigh
Sanding Balsa Wood prior to sortingSanding Balsa Wood prior to sorting
Comparison of woods
Species Wt
lbscf
StiffnessStrength
BendingStrength
CompressionStrength
Balsa 8 72 70 75
Balsa 14 156 161 149
Spruce 28 230 260 289
Basswood
26 261 288 288
Wood Characteristics
bull Anistropic means having properties that differ depending on direction
bull Wood has grain to it and will react differently depending on the grain
bull Consider how grain affects how wood reacts and build your structure with this in mind
Moisture
bull Wood absorbs moisture from the air (especially balsa wood)
bull When weight is a consideration teams may want to consider ways to remove moisture from their structure
bull Many teams try to control the moisture absorption by the wood
bull Others try to remove moisture prior to weigh in
Moisture
bull Teams may find that certain glues degrade when exposed to extreme heat(thus the structure is weaker after drying)
bull Teams should brainstorm quantify and test any techniques they consider for removing moisture from their structure
General Definitions
bull Structure
bull Column
bull Brace
bull Member
bull Stress (Forces)
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
What is a Structure
bull A structure is anything made up of a number of parts that are held together in a particular way and has a base or foundation
bull All structures give support or provide a framework You can find structures everywhere Bridges buildings chairs shoes plants spider webs tables and even your own body are all structures A structures shape size and what its made of depend on what the structure does and how strong it needs to be
bull Form and FunctionEvery structure has form and function Form and Function are interconnected
The shape (or form) of something affects its purpose (or function)
Something with a certain shape can have more than one purpose or function
bull Forces of Tension and CompressionEvery structure is affected by forces
The force of one structure can affect another
The affect can go back and forth with a push and pull force
Compression and Tension are examples of push and pull forces
Compression the state of a material pressed together or forced into less space
Tension a stress on a material made by the pull of forces extending outwards
Structures in the Real World
You can find inspiration all around you if you just lookYou can find inspiration all around you if you just look
6 Flags ndash Texas Giant6 Flags ndash Texas Giant
6 Flags ndash G Force6 Flags ndash G Force
6 Flags ndash Bob Sled6 Flags ndash Bob Sled
6 Flags ndash Judge Roy Scream Roller Coaster6 Flags ndash Judge Roy Scream Roller Coaster
Construction Project ndash Masonry ScaffoldingConstruction Project ndash Masonry Scaffolding
DFW Airport ndash Tower Cranes used constructing new TerminalDFW Airport ndash Tower Cranes used constructing new Terminal
Six Flags ndash The TitanSix Flags ndash The Titan
DFW Airport ndash Doppler RadarDFW Airport ndash Doppler Radar
Six Flags ndash Mister FreezeSix Flags ndash Mister Freeze
Electrical Wire Transmission TowerElectrical Wire Transmission Tower
Six Flags Oil DerrickSix Flags Oil Derrick
DFW Airport - Scaffolding holding up concrete formsDFW Airport - Scaffolding holding up concrete forms
BasicConcepts
ampDefinitions
Intro to teaching basic structure
bull Wood
bull Jigs
bull Forces
bull Glue
bull Tools and More Tools
bull Construction Area
bull This yearrsquos Challenge
bull The Duct Tape Challenge
bull Summary
Construction Area
A large open table where team can place building jigs weigh wood saw and cut materials assemble amp finish structures
Cover the table top (sheet of thick plastic or masonite)Make sure that work areas are kept well ventilated especially when teams are using glues with harmful vapors
Cutting Tools and EquipmentCutting Tools and Equipment
Helping teams learnabout wood characteristics
bull Wood
ndash Wood comes in a variety of dimensions (sticks and planks)
ndash Hobby stores carry balsa and basswood (basswood generally denser and heavier)
ndash USA Balsa and SIG has a large assortment of wood (wwwsigmfgcom) ndash Factors to consider
bull Weightbull Strengthbull Ease of use
Wood Hands on
bull Examine the wood forndash Texturendash Grainndash Smoothnessndash Kerf marks
bull How porous is itbull How easy does a stick bendbull How much does it weigh
Sanding Balsa Wood prior to sortingSanding Balsa Wood prior to sorting
Comparison of woods
Species Wt
lbscf
StiffnessStrength
BendingStrength
CompressionStrength
Balsa 8 72 70 75
Balsa 14 156 161 149
Spruce 28 230 260 289
Basswood
26 261 288 288
Wood Characteristics
bull Anistropic means having properties that differ depending on direction
bull Wood has grain to it and will react differently depending on the grain
bull Consider how grain affects how wood reacts and build your structure with this in mind
Moisture
bull Wood absorbs moisture from the air (especially balsa wood)
bull When weight is a consideration teams may want to consider ways to remove moisture from their structure
bull Many teams try to control the moisture absorption by the wood
bull Others try to remove moisture prior to weigh in
Moisture
bull Teams may find that certain glues degrade when exposed to extreme heat(thus the structure is weaker after drying)
bull Teams should brainstorm quantify and test any techniques they consider for removing moisture from their structure
General Definitions
bull Structure
bull Column
bull Brace
bull Member
bull Stress (Forces)
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
bull Form and FunctionEvery structure has form and function Form and Function are interconnected
The shape (or form) of something affects its purpose (or function)
Something with a certain shape can have more than one purpose or function
bull Forces of Tension and CompressionEvery structure is affected by forces
The force of one structure can affect another
The affect can go back and forth with a push and pull force
Compression and Tension are examples of push and pull forces
Compression the state of a material pressed together or forced into less space
Tension a stress on a material made by the pull of forces extending outwards
Structures in the Real World
You can find inspiration all around you if you just lookYou can find inspiration all around you if you just look
6 Flags ndash Texas Giant6 Flags ndash Texas Giant
6 Flags ndash G Force6 Flags ndash G Force
6 Flags ndash Bob Sled6 Flags ndash Bob Sled
6 Flags ndash Judge Roy Scream Roller Coaster6 Flags ndash Judge Roy Scream Roller Coaster
Construction Project ndash Masonry ScaffoldingConstruction Project ndash Masonry Scaffolding
DFW Airport ndash Tower Cranes used constructing new TerminalDFW Airport ndash Tower Cranes used constructing new Terminal
Six Flags ndash The TitanSix Flags ndash The Titan
DFW Airport ndash Doppler RadarDFW Airport ndash Doppler Radar
Six Flags ndash Mister FreezeSix Flags ndash Mister Freeze
Electrical Wire Transmission TowerElectrical Wire Transmission Tower
Six Flags Oil DerrickSix Flags Oil Derrick
DFW Airport - Scaffolding holding up concrete formsDFW Airport - Scaffolding holding up concrete forms
BasicConcepts
ampDefinitions
Intro to teaching basic structure
bull Wood
bull Jigs
bull Forces
bull Glue
bull Tools and More Tools
bull Construction Area
bull This yearrsquos Challenge
bull The Duct Tape Challenge
bull Summary
Construction Area
A large open table where team can place building jigs weigh wood saw and cut materials assemble amp finish structures
Cover the table top (sheet of thick plastic or masonite)Make sure that work areas are kept well ventilated especially when teams are using glues with harmful vapors
Cutting Tools and EquipmentCutting Tools and Equipment
Helping teams learnabout wood characteristics
bull Wood
ndash Wood comes in a variety of dimensions (sticks and planks)
ndash Hobby stores carry balsa and basswood (basswood generally denser and heavier)
ndash USA Balsa and SIG has a large assortment of wood (wwwsigmfgcom) ndash Factors to consider
bull Weightbull Strengthbull Ease of use
Wood Hands on
bull Examine the wood forndash Texturendash Grainndash Smoothnessndash Kerf marks
bull How porous is itbull How easy does a stick bendbull How much does it weigh
Sanding Balsa Wood prior to sortingSanding Balsa Wood prior to sorting
Comparison of woods
Species Wt
lbscf
StiffnessStrength
BendingStrength
CompressionStrength
Balsa 8 72 70 75
Balsa 14 156 161 149
Spruce 28 230 260 289
Basswood
26 261 288 288
Wood Characteristics
bull Anistropic means having properties that differ depending on direction
bull Wood has grain to it and will react differently depending on the grain
bull Consider how grain affects how wood reacts and build your structure with this in mind
Moisture
bull Wood absorbs moisture from the air (especially balsa wood)
bull When weight is a consideration teams may want to consider ways to remove moisture from their structure
bull Many teams try to control the moisture absorption by the wood
bull Others try to remove moisture prior to weigh in
Moisture
bull Teams may find that certain glues degrade when exposed to extreme heat(thus the structure is weaker after drying)
bull Teams should brainstorm quantify and test any techniques they consider for removing moisture from their structure
General Definitions
bull Structure
bull Column
bull Brace
bull Member
bull Stress (Forces)
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Structures in the Real World
You can find inspiration all around you if you just lookYou can find inspiration all around you if you just look
6 Flags ndash Texas Giant6 Flags ndash Texas Giant
6 Flags ndash G Force6 Flags ndash G Force
6 Flags ndash Bob Sled6 Flags ndash Bob Sled
6 Flags ndash Judge Roy Scream Roller Coaster6 Flags ndash Judge Roy Scream Roller Coaster
Construction Project ndash Masonry ScaffoldingConstruction Project ndash Masonry Scaffolding
DFW Airport ndash Tower Cranes used constructing new TerminalDFW Airport ndash Tower Cranes used constructing new Terminal
Six Flags ndash The TitanSix Flags ndash The Titan
DFW Airport ndash Doppler RadarDFW Airport ndash Doppler Radar
Six Flags ndash Mister FreezeSix Flags ndash Mister Freeze
Electrical Wire Transmission TowerElectrical Wire Transmission Tower
Six Flags Oil DerrickSix Flags Oil Derrick
DFW Airport - Scaffolding holding up concrete formsDFW Airport - Scaffolding holding up concrete forms
BasicConcepts
ampDefinitions
Intro to teaching basic structure
bull Wood
bull Jigs
bull Forces
bull Glue
bull Tools and More Tools
bull Construction Area
bull This yearrsquos Challenge
bull The Duct Tape Challenge
bull Summary
Construction Area
A large open table where team can place building jigs weigh wood saw and cut materials assemble amp finish structures
Cover the table top (sheet of thick plastic or masonite)Make sure that work areas are kept well ventilated especially when teams are using glues with harmful vapors
Cutting Tools and EquipmentCutting Tools and Equipment
Helping teams learnabout wood characteristics
bull Wood
ndash Wood comes in a variety of dimensions (sticks and planks)
ndash Hobby stores carry balsa and basswood (basswood generally denser and heavier)
ndash USA Balsa and SIG has a large assortment of wood (wwwsigmfgcom) ndash Factors to consider
bull Weightbull Strengthbull Ease of use
Wood Hands on
bull Examine the wood forndash Texturendash Grainndash Smoothnessndash Kerf marks
bull How porous is itbull How easy does a stick bendbull How much does it weigh
Sanding Balsa Wood prior to sortingSanding Balsa Wood prior to sorting
Comparison of woods
Species Wt
lbscf
StiffnessStrength
BendingStrength
CompressionStrength
Balsa 8 72 70 75
Balsa 14 156 161 149
Spruce 28 230 260 289
Basswood
26 261 288 288
Wood Characteristics
bull Anistropic means having properties that differ depending on direction
bull Wood has grain to it and will react differently depending on the grain
bull Consider how grain affects how wood reacts and build your structure with this in mind
Moisture
bull Wood absorbs moisture from the air (especially balsa wood)
bull When weight is a consideration teams may want to consider ways to remove moisture from their structure
bull Many teams try to control the moisture absorption by the wood
bull Others try to remove moisture prior to weigh in
Moisture
bull Teams may find that certain glues degrade when exposed to extreme heat(thus the structure is weaker after drying)
bull Teams should brainstorm quantify and test any techniques they consider for removing moisture from their structure
General Definitions
bull Structure
bull Column
bull Brace
bull Member
bull Stress (Forces)
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
6 Flags ndash Texas Giant6 Flags ndash Texas Giant
6 Flags ndash G Force6 Flags ndash G Force
6 Flags ndash Bob Sled6 Flags ndash Bob Sled
6 Flags ndash Judge Roy Scream Roller Coaster6 Flags ndash Judge Roy Scream Roller Coaster
Construction Project ndash Masonry ScaffoldingConstruction Project ndash Masonry Scaffolding
DFW Airport ndash Tower Cranes used constructing new TerminalDFW Airport ndash Tower Cranes used constructing new Terminal
Six Flags ndash The TitanSix Flags ndash The Titan
DFW Airport ndash Doppler RadarDFW Airport ndash Doppler Radar
Six Flags ndash Mister FreezeSix Flags ndash Mister Freeze
Electrical Wire Transmission TowerElectrical Wire Transmission Tower
Six Flags Oil DerrickSix Flags Oil Derrick
DFW Airport - Scaffolding holding up concrete formsDFW Airport - Scaffolding holding up concrete forms
BasicConcepts
ampDefinitions
Intro to teaching basic structure
bull Wood
bull Jigs
bull Forces
bull Glue
bull Tools and More Tools
bull Construction Area
bull This yearrsquos Challenge
bull The Duct Tape Challenge
bull Summary
Construction Area
A large open table where team can place building jigs weigh wood saw and cut materials assemble amp finish structures
Cover the table top (sheet of thick plastic or masonite)Make sure that work areas are kept well ventilated especially when teams are using glues with harmful vapors
Cutting Tools and EquipmentCutting Tools and Equipment
Helping teams learnabout wood characteristics
bull Wood
ndash Wood comes in a variety of dimensions (sticks and planks)
ndash Hobby stores carry balsa and basswood (basswood generally denser and heavier)
ndash USA Balsa and SIG has a large assortment of wood (wwwsigmfgcom) ndash Factors to consider
bull Weightbull Strengthbull Ease of use
Wood Hands on
bull Examine the wood forndash Texturendash Grainndash Smoothnessndash Kerf marks
bull How porous is itbull How easy does a stick bendbull How much does it weigh
Sanding Balsa Wood prior to sortingSanding Balsa Wood prior to sorting
Comparison of woods
Species Wt
lbscf
StiffnessStrength
BendingStrength
CompressionStrength
Balsa 8 72 70 75
Balsa 14 156 161 149
Spruce 28 230 260 289
Basswood
26 261 288 288
Wood Characteristics
bull Anistropic means having properties that differ depending on direction
bull Wood has grain to it and will react differently depending on the grain
bull Consider how grain affects how wood reacts and build your structure with this in mind
Moisture
bull Wood absorbs moisture from the air (especially balsa wood)
bull When weight is a consideration teams may want to consider ways to remove moisture from their structure
bull Many teams try to control the moisture absorption by the wood
bull Others try to remove moisture prior to weigh in
Moisture
bull Teams may find that certain glues degrade when exposed to extreme heat(thus the structure is weaker after drying)
bull Teams should brainstorm quantify and test any techniques they consider for removing moisture from their structure
General Definitions
bull Structure
bull Column
bull Brace
bull Member
bull Stress (Forces)
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
6 Flags ndash G Force6 Flags ndash G Force
6 Flags ndash Bob Sled6 Flags ndash Bob Sled
6 Flags ndash Judge Roy Scream Roller Coaster6 Flags ndash Judge Roy Scream Roller Coaster
Construction Project ndash Masonry ScaffoldingConstruction Project ndash Masonry Scaffolding
DFW Airport ndash Tower Cranes used constructing new TerminalDFW Airport ndash Tower Cranes used constructing new Terminal
Six Flags ndash The TitanSix Flags ndash The Titan
DFW Airport ndash Doppler RadarDFW Airport ndash Doppler Radar
Six Flags ndash Mister FreezeSix Flags ndash Mister Freeze
Electrical Wire Transmission TowerElectrical Wire Transmission Tower
Six Flags Oil DerrickSix Flags Oil Derrick
DFW Airport - Scaffolding holding up concrete formsDFW Airport - Scaffolding holding up concrete forms
BasicConcepts
ampDefinitions
Intro to teaching basic structure
bull Wood
bull Jigs
bull Forces
bull Glue
bull Tools and More Tools
bull Construction Area
bull This yearrsquos Challenge
bull The Duct Tape Challenge
bull Summary
Construction Area
A large open table where team can place building jigs weigh wood saw and cut materials assemble amp finish structures
Cover the table top (sheet of thick plastic or masonite)Make sure that work areas are kept well ventilated especially when teams are using glues with harmful vapors
Cutting Tools and EquipmentCutting Tools and Equipment
Helping teams learnabout wood characteristics
bull Wood
ndash Wood comes in a variety of dimensions (sticks and planks)
ndash Hobby stores carry balsa and basswood (basswood generally denser and heavier)
ndash USA Balsa and SIG has a large assortment of wood (wwwsigmfgcom) ndash Factors to consider
bull Weightbull Strengthbull Ease of use
Wood Hands on
bull Examine the wood forndash Texturendash Grainndash Smoothnessndash Kerf marks
bull How porous is itbull How easy does a stick bendbull How much does it weigh
Sanding Balsa Wood prior to sortingSanding Balsa Wood prior to sorting
Comparison of woods
Species Wt
lbscf
StiffnessStrength
BendingStrength
CompressionStrength
Balsa 8 72 70 75
Balsa 14 156 161 149
Spruce 28 230 260 289
Basswood
26 261 288 288
Wood Characteristics
bull Anistropic means having properties that differ depending on direction
bull Wood has grain to it and will react differently depending on the grain
bull Consider how grain affects how wood reacts and build your structure with this in mind
Moisture
bull Wood absorbs moisture from the air (especially balsa wood)
bull When weight is a consideration teams may want to consider ways to remove moisture from their structure
bull Many teams try to control the moisture absorption by the wood
bull Others try to remove moisture prior to weigh in
Moisture
bull Teams may find that certain glues degrade when exposed to extreme heat(thus the structure is weaker after drying)
bull Teams should brainstorm quantify and test any techniques they consider for removing moisture from their structure
General Definitions
bull Structure
bull Column
bull Brace
bull Member
bull Stress (Forces)
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
6 Flags ndash Bob Sled6 Flags ndash Bob Sled
6 Flags ndash Judge Roy Scream Roller Coaster6 Flags ndash Judge Roy Scream Roller Coaster
Construction Project ndash Masonry ScaffoldingConstruction Project ndash Masonry Scaffolding
DFW Airport ndash Tower Cranes used constructing new TerminalDFW Airport ndash Tower Cranes used constructing new Terminal
Six Flags ndash The TitanSix Flags ndash The Titan
DFW Airport ndash Doppler RadarDFW Airport ndash Doppler Radar
Six Flags ndash Mister FreezeSix Flags ndash Mister Freeze
Electrical Wire Transmission TowerElectrical Wire Transmission Tower
Six Flags Oil DerrickSix Flags Oil Derrick
DFW Airport - Scaffolding holding up concrete formsDFW Airport - Scaffolding holding up concrete forms
BasicConcepts
ampDefinitions
Intro to teaching basic structure
bull Wood
bull Jigs
bull Forces
bull Glue
bull Tools and More Tools
bull Construction Area
bull This yearrsquos Challenge
bull The Duct Tape Challenge
bull Summary
Construction Area
A large open table where team can place building jigs weigh wood saw and cut materials assemble amp finish structures
Cover the table top (sheet of thick plastic or masonite)Make sure that work areas are kept well ventilated especially when teams are using glues with harmful vapors
Cutting Tools and EquipmentCutting Tools and Equipment
Helping teams learnabout wood characteristics
bull Wood
ndash Wood comes in a variety of dimensions (sticks and planks)
ndash Hobby stores carry balsa and basswood (basswood generally denser and heavier)
ndash USA Balsa and SIG has a large assortment of wood (wwwsigmfgcom) ndash Factors to consider
bull Weightbull Strengthbull Ease of use
Wood Hands on
bull Examine the wood forndash Texturendash Grainndash Smoothnessndash Kerf marks
bull How porous is itbull How easy does a stick bendbull How much does it weigh
Sanding Balsa Wood prior to sortingSanding Balsa Wood prior to sorting
Comparison of woods
Species Wt
lbscf
StiffnessStrength
BendingStrength
CompressionStrength
Balsa 8 72 70 75
Balsa 14 156 161 149
Spruce 28 230 260 289
Basswood
26 261 288 288
Wood Characteristics
bull Anistropic means having properties that differ depending on direction
bull Wood has grain to it and will react differently depending on the grain
bull Consider how grain affects how wood reacts and build your structure with this in mind
Moisture
bull Wood absorbs moisture from the air (especially balsa wood)
bull When weight is a consideration teams may want to consider ways to remove moisture from their structure
bull Many teams try to control the moisture absorption by the wood
bull Others try to remove moisture prior to weigh in
Moisture
bull Teams may find that certain glues degrade when exposed to extreme heat(thus the structure is weaker after drying)
bull Teams should brainstorm quantify and test any techniques they consider for removing moisture from their structure
General Definitions
bull Structure
bull Column
bull Brace
bull Member
bull Stress (Forces)
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
6 Flags ndash Judge Roy Scream Roller Coaster6 Flags ndash Judge Roy Scream Roller Coaster
Construction Project ndash Masonry ScaffoldingConstruction Project ndash Masonry Scaffolding
DFW Airport ndash Tower Cranes used constructing new TerminalDFW Airport ndash Tower Cranes used constructing new Terminal
Six Flags ndash The TitanSix Flags ndash The Titan
DFW Airport ndash Doppler RadarDFW Airport ndash Doppler Radar
Six Flags ndash Mister FreezeSix Flags ndash Mister Freeze
Electrical Wire Transmission TowerElectrical Wire Transmission Tower
Six Flags Oil DerrickSix Flags Oil Derrick
DFW Airport - Scaffolding holding up concrete formsDFW Airport - Scaffolding holding up concrete forms
BasicConcepts
ampDefinitions
Intro to teaching basic structure
bull Wood
bull Jigs
bull Forces
bull Glue
bull Tools and More Tools
bull Construction Area
bull This yearrsquos Challenge
bull The Duct Tape Challenge
bull Summary
Construction Area
A large open table where team can place building jigs weigh wood saw and cut materials assemble amp finish structures
Cover the table top (sheet of thick plastic or masonite)Make sure that work areas are kept well ventilated especially when teams are using glues with harmful vapors
Cutting Tools and EquipmentCutting Tools and Equipment
Helping teams learnabout wood characteristics
bull Wood
ndash Wood comes in a variety of dimensions (sticks and planks)
ndash Hobby stores carry balsa and basswood (basswood generally denser and heavier)
ndash USA Balsa and SIG has a large assortment of wood (wwwsigmfgcom) ndash Factors to consider
bull Weightbull Strengthbull Ease of use
Wood Hands on
bull Examine the wood forndash Texturendash Grainndash Smoothnessndash Kerf marks
bull How porous is itbull How easy does a stick bendbull How much does it weigh
Sanding Balsa Wood prior to sortingSanding Balsa Wood prior to sorting
Comparison of woods
Species Wt
lbscf
StiffnessStrength
BendingStrength
CompressionStrength
Balsa 8 72 70 75
Balsa 14 156 161 149
Spruce 28 230 260 289
Basswood
26 261 288 288
Wood Characteristics
bull Anistropic means having properties that differ depending on direction
bull Wood has grain to it and will react differently depending on the grain
bull Consider how grain affects how wood reacts and build your structure with this in mind
Moisture
bull Wood absorbs moisture from the air (especially balsa wood)
bull When weight is a consideration teams may want to consider ways to remove moisture from their structure
bull Many teams try to control the moisture absorption by the wood
bull Others try to remove moisture prior to weigh in
Moisture
bull Teams may find that certain glues degrade when exposed to extreme heat(thus the structure is weaker after drying)
bull Teams should brainstorm quantify and test any techniques they consider for removing moisture from their structure
General Definitions
bull Structure
bull Column
bull Brace
bull Member
bull Stress (Forces)
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Construction Project ndash Masonry ScaffoldingConstruction Project ndash Masonry Scaffolding
DFW Airport ndash Tower Cranes used constructing new TerminalDFW Airport ndash Tower Cranes used constructing new Terminal
Six Flags ndash The TitanSix Flags ndash The Titan
DFW Airport ndash Doppler RadarDFW Airport ndash Doppler Radar
Six Flags ndash Mister FreezeSix Flags ndash Mister Freeze
Electrical Wire Transmission TowerElectrical Wire Transmission Tower
Six Flags Oil DerrickSix Flags Oil Derrick
DFW Airport - Scaffolding holding up concrete formsDFW Airport - Scaffolding holding up concrete forms
BasicConcepts
ampDefinitions
Intro to teaching basic structure
bull Wood
bull Jigs
bull Forces
bull Glue
bull Tools and More Tools
bull Construction Area
bull This yearrsquos Challenge
bull The Duct Tape Challenge
bull Summary
Construction Area
A large open table where team can place building jigs weigh wood saw and cut materials assemble amp finish structures
Cover the table top (sheet of thick plastic or masonite)Make sure that work areas are kept well ventilated especially when teams are using glues with harmful vapors
Cutting Tools and EquipmentCutting Tools and Equipment
Helping teams learnabout wood characteristics
bull Wood
ndash Wood comes in a variety of dimensions (sticks and planks)
ndash Hobby stores carry balsa and basswood (basswood generally denser and heavier)
ndash USA Balsa and SIG has a large assortment of wood (wwwsigmfgcom) ndash Factors to consider
bull Weightbull Strengthbull Ease of use
Wood Hands on
bull Examine the wood forndash Texturendash Grainndash Smoothnessndash Kerf marks
bull How porous is itbull How easy does a stick bendbull How much does it weigh
Sanding Balsa Wood prior to sortingSanding Balsa Wood prior to sorting
Comparison of woods
Species Wt
lbscf
StiffnessStrength
BendingStrength
CompressionStrength
Balsa 8 72 70 75
Balsa 14 156 161 149
Spruce 28 230 260 289
Basswood
26 261 288 288
Wood Characteristics
bull Anistropic means having properties that differ depending on direction
bull Wood has grain to it and will react differently depending on the grain
bull Consider how grain affects how wood reacts and build your structure with this in mind
Moisture
bull Wood absorbs moisture from the air (especially balsa wood)
bull When weight is a consideration teams may want to consider ways to remove moisture from their structure
bull Many teams try to control the moisture absorption by the wood
bull Others try to remove moisture prior to weigh in
Moisture
bull Teams may find that certain glues degrade when exposed to extreme heat(thus the structure is weaker after drying)
bull Teams should brainstorm quantify and test any techniques they consider for removing moisture from their structure
General Definitions
bull Structure
bull Column
bull Brace
bull Member
bull Stress (Forces)
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
DFW Airport ndash Tower Cranes used constructing new TerminalDFW Airport ndash Tower Cranes used constructing new Terminal
Six Flags ndash The TitanSix Flags ndash The Titan
DFW Airport ndash Doppler RadarDFW Airport ndash Doppler Radar
Six Flags ndash Mister FreezeSix Flags ndash Mister Freeze
Electrical Wire Transmission TowerElectrical Wire Transmission Tower
Six Flags Oil DerrickSix Flags Oil Derrick
DFW Airport - Scaffolding holding up concrete formsDFW Airport - Scaffolding holding up concrete forms
BasicConcepts
ampDefinitions
Intro to teaching basic structure
bull Wood
bull Jigs
bull Forces
bull Glue
bull Tools and More Tools
bull Construction Area
bull This yearrsquos Challenge
bull The Duct Tape Challenge
bull Summary
Construction Area
A large open table where team can place building jigs weigh wood saw and cut materials assemble amp finish structures
Cover the table top (sheet of thick plastic or masonite)Make sure that work areas are kept well ventilated especially when teams are using glues with harmful vapors
Cutting Tools and EquipmentCutting Tools and Equipment
Helping teams learnabout wood characteristics
bull Wood
ndash Wood comes in a variety of dimensions (sticks and planks)
ndash Hobby stores carry balsa and basswood (basswood generally denser and heavier)
ndash USA Balsa and SIG has a large assortment of wood (wwwsigmfgcom) ndash Factors to consider
bull Weightbull Strengthbull Ease of use
Wood Hands on
bull Examine the wood forndash Texturendash Grainndash Smoothnessndash Kerf marks
bull How porous is itbull How easy does a stick bendbull How much does it weigh
Sanding Balsa Wood prior to sortingSanding Balsa Wood prior to sorting
Comparison of woods
Species Wt
lbscf
StiffnessStrength
BendingStrength
CompressionStrength
Balsa 8 72 70 75
Balsa 14 156 161 149
Spruce 28 230 260 289
Basswood
26 261 288 288
Wood Characteristics
bull Anistropic means having properties that differ depending on direction
bull Wood has grain to it and will react differently depending on the grain
bull Consider how grain affects how wood reacts and build your structure with this in mind
Moisture
bull Wood absorbs moisture from the air (especially balsa wood)
bull When weight is a consideration teams may want to consider ways to remove moisture from their structure
bull Many teams try to control the moisture absorption by the wood
bull Others try to remove moisture prior to weigh in
Moisture
bull Teams may find that certain glues degrade when exposed to extreme heat(thus the structure is weaker after drying)
bull Teams should brainstorm quantify and test any techniques they consider for removing moisture from their structure
General Definitions
bull Structure
bull Column
bull Brace
bull Member
bull Stress (Forces)
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Six Flags ndash The TitanSix Flags ndash The Titan
DFW Airport ndash Doppler RadarDFW Airport ndash Doppler Radar
Six Flags ndash Mister FreezeSix Flags ndash Mister Freeze
Electrical Wire Transmission TowerElectrical Wire Transmission Tower
Six Flags Oil DerrickSix Flags Oil Derrick
DFW Airport - Scaffolding holding up concrete formsDFW Airport - Scaffolding holding up concrete forms
BasicConcepts
ampDefinitions
Intro to teaching basic structure
bull Wood
bull Jigs
bull Forces
bull Glue
bull Tools and More Tools
bull Construction Area
bull This yearrsquos Challenge
bull The Duct Tape Challenge
bull Summary
Construction Area
A large open table where team can place building jigs weigh wood saw and cut materials assemble amp finish structures
Cover the table top (sheet of thick plastic or masonite)Make sure that work areas are kept well ventilated especially when teams are using glues with harmful vapors
Cutting Tools and EquipmentCutting Tools and Equipment
Helping teams learnabout wood characteristics
bull Wood
ndash Wood comes in a variety of dimensions (sticks and planks)
ndash Hobby stores carry balsa and basswood (basswood generally denser and heavier)
ndash USA Balsa and SIG has a large assortment of wood (wwwsigmfgcom) ndash Factors to consider
bull Weightbull Strengthbull Ease of use
Wood Hands on
bull Examine the wood forndash Texturendash Grainndash Smoothnessndash Kerf marks
bull How porous is itbull How easy does a stick bendbull How much does it weigh
Sanding Balsa Wood prior to sortingSanding Balsa Wood prior to sorting
Comparison of woods
Species Wt
lbscf
StiffnessStrength
BendingStrength
CompressionStrength
Balsa 8 72 70 75
Balsa 14 156 161 149
Spruce 28 230 260 289
Basswood
26 261 288 288
Wood Characteristics
bull Anistropic means having properties that differ depending on direction
bull Wood has grain to it and will react differently depending on the grain
bull Consider how grain affects how wood reacts and build your structure with this in mind
Moisture
bull Wood absorbs moisture from the air (especially balsa wood)
bull When weight is a consideration teams may want to consider ways to remove moisture from their structure
bull Many teams try to control the moisture absorption by the wood
bull Others try to remove moisture prior to weigh in
Moisture
bull Teams may find that certain glues degrade when exposed to extreme heat(thus the structure is weaker after drying)
bull Teams should brainstorm quantify and test any techniques they consider for removing moisture from their structure
General Definitions
bull Structure
bull Column
bull Brace
bull Member
bull Stress (Forces)
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
DFW Airport ndash Doppler RadarDFW Airport ndash Doppler Radar
Six Flags ndash Mister FreezeSix Flags ndash Mister Freeze
Electrical Wire Transmission TowerElectrical Wire Transmission Tower
Six Flags Oil DerrickSix Flags Oil Derrick
DFW Airport - Scaffolding holding up concrete formsDFW Airport - Scaffolding holding up concrete forms
BasicConcepts
ampDefinitions
Intro to teaching basic structure
bull Wood
bull Jigs
bull Forces
bull Glue
bull Tools and More Tools
bull Construction Area
bull This yearrsquos Challenge
bull The Duct Tape Challenge
bull Summary
Construction Area
A large open table where team can place building jigs weigh wood saw and cut materials assemble amp finish structures
Cover the table top (sheet of thick plastic or masonite)Make sure that work areas are kept well ventilated especially when teams are using glues with harmful vapors
Cutting Tools and EquipmentCutting Tools and Equipment
Helping teams learnabout wood characteristics
bull Wood
ndash Wood comes in a variety of dimensions (sticks and planks)
ndash Hobby stores carry balsa and basswood (basswood generally denser and heavier)
ndash USA Balsa and SIG has a large assortment of wood (wwwsigmfgcom) ndash Factors to consider
bull Weightbull Strengthbull Ease of use
Wood Hands on
bull Examine the wood forndash Texturendash Grainndash Smoothnessndash Kerf marks
bull How porous is itbull How easy does a stick bendbull How much does it weigh
Sanding Balsa Wood prior to sortingSanding Balsa Wood prior to sorting
Comparison of woods
Species Wt
lbscf
StiffnessStrength
BendingStrength
CompressionStrength
Balsa 8 72 70 75
Balsa 14 156 161 149
Spruce 28 230 260 289
Basswood
26 261 288 288
Wood Characteristics
bull Anistropic means having properties that differ depending on direction
bull Wood has grain to it and will react differently depending on the grain
bull Consider how grain affects how wood reacts and build your structure with this in mind
Moisture
bull Wood absorbs moisture from the air (especially balsa wood)
bull When weight is a consideration teams may want to consider ways to remove moisture from their structure
bull Many teams try to control the moisture absorption by the wood
bull Others try to remove moisture prior to weigh in
Moisture
bull Teams may find that certain glues degrade when exposed to extreme heat(thus the structure is weaker after drying)
bull Teams should brainstorm quantify and test any techniques they consider for removing moisture from their structure
General Definitions
bull Structure
bull Column
bull Brace
bull Member
bull Stress (Forces)
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Six Flags ndash Mister FreezeSix Flags ndash Mister Freeze
Electrical Wire Transmission TowerElectrical Wire Transmission Tower
Six Flags Oil DerrickSix Flags Oil Derrick
DFW Airport - Scaffolding holding up concrete formsDFW Airport - Scaffolding holding up concrete forms
BasicConcepts
ampDefinitions
Intro to teaching basic structure
bull Wood
bull Jigs
bull Forces
bull Glue
bull Tools and More Tools
bull Construction Area
bull This yearrsquos Challenge
bull The Duct Tape Challenge
bull Summary
Construction Area
A large open table where team can place building jigs weigh wood saw and cut materials assemble amp finish structures
Cover the table top (sheet of thick plastic or masonite)Make sure that work areas are kept well ventilated especially when teams are using glues with harmful vapors
Cutting Tools and EquipmentCutting Tools and Equipment
Helping teams learnabout wood characteristics
bull Wood
ndash Wood comes in a variety of dimensions (sticks and planks)
ndash Hobby stores carry balsa and basswood (basswood generally denser and heavier)
ndash USA Balsa and SIG has a large assortment of wood (wwwsigmfgcom) ndash Factors to consider
bull Weightbull Strengthbull Ease of use
Wood Hands on
bull Examine the wood forndash Texturendash Grainndash Smoothnessndash Kerf marks
bull How porous is itbull How easy does a stick bendbull How much does it weigh
Sanding Balsa Wood prior to sortingSanding Balsa Wood prior to sorting
Comparison of woods
Species Wt
lbscf
StiffnessStrength
BendingStrength
CompressionStrength
Balsa 8 72 70 75
Balsa 14 156 161 149
Spruce 28 230 260 289
Basswood
26 261 288 288
Wood Characteristics
bull Anistropic means having properties that differ depending on direction
bull Wood has grain to it and will react differently depending on the grain
bull Consider how grain affects how wood reacts and build your structure with this in mind
Moisture
bull Wood absorbs moisture from the air (especially balsa wood)
bull When weight is a consideration teams may want to consider ways to remove moisture from their structure
bull Many teams try to control the moisture absorption by the wood
bull Others try to remove moisture prior to weigh in
Moisture
bull Teams may find that certain glues degrade when exposed to extreme heat(thus the structure is weaker after drying)
bull Teams should brainstorm quantify and test any techniques they consider for removing moisture from their structure
General Definitions
bull Structure
bull Column
bull Brace
bull Member
bull Stress (Forces)
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Electrical Wire Transmission TowerElectrical Wire Transmission Tower
Six Flags Oil DerrickSix Flags Oil Derrick
DFW Airport - Scaffolding holding up concrete formsDFW Airport - Scaffolding holding up concrete forms
BasicConcepts
ampDefinitions
Intro to teaching basic structure
bull Wood
bull Jigs
bull Forces
bull Glue
bull Tools and More Tools
bull Construction Area
bull This yearrsquos Challenge
bull The Duct Tape Challenge
bull Summary
Construction Area
A large open table where team can place building jigs weigh wood saw and cut materials assemble amp finish structures
Cover the table top (sheet of thick plastic or masonite)Make sure that work areas are kept well ventilated especially when teams are using glues with harmful vapors
Cutting Tools and EquipmentCutting Tools and Equipment
Helping teams learnabout wood characteristics
bull Wood
ndash Wood comes in a variety of dimensions (sticks and planks)
ndash Hobby stores carry balsa and basswood (basswood generally denser and heavier)
ndash USA Balsa and SIG has a large assortment of wood (wwwsigmfgcom) ndash Factors to consider
bull Weightbull Strengthbull Ease of use
Wood Hands on
bull Examine the wood forndash Texturendash Grainndash Smoothnessndash Kerf marks
bull How porous is itbull How easy does a stick bendbull How much does it weigh
Sanding Balsa Wood prior to sortingSanding Balsa Wood prior to sorting
Comparison of woods
Species Wt
lbscf
StiffnessStrength
BendingStrength
CompressionStrength
Balsa 8 72 70 75
Balsa 14 156 161 149
Spruce 28 230 260 289
Basswood
26 261 288 288
Wood Characteristics
bull Anistropic means having properties that differ depending on direction
bull Wood has grain to it and will react differently depending on the grain
bull Consider how grain affects how wood reacts and build your structure with this in mind
Moisture
bull Wood absorbs moisture from the air (especially balsa wood)
bull When weight is a consideration teams may want to consider ways to remove moisture from their structure
bull Many teams try to control the moisture absorption by the wood
bull Others try to remove moisture prior to weigh in
Moisture
bull Teams may find that certain glues degrade when exposed to extreme heat(thus the structure is weaker after drying)
bull Teams should brainstorm quantify and test any techniques they consider for removing moisture from their structure
General Definitions
bull Structure
bull Column
bull Brace
bull Member
bull Stress (Forces)
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Six Flags Oil DerrickSix Flags Oil Derrick
DFW Airport - Scaffolding holding up concrete formsDFW Airport - Scaffolding holding up concrete forms
BasicConcepts
ampDefinitions
Intro to teaching basic structure
bull Wood
bull Jigs
bull Forces
bull Glue
bull Tools and More Tools
bull Construction Area
bull This yearrsquos Challenge
bull The Duct Tape Challenge
bull Summary
Construction Area
A large open table where team can place building jigs weigh wood saw and cut materials assemble amp finish structures
Cover the table top (sheet of thick plastic or masonite)Make sure that work areas are kept well ventilated especially when teams are using glues with harmful vapors
Cutting Tools and EquipmentCutting Tools and Equipment
Helping teams learnabout wood characteristics
bull Wood
ndash Wood comes in a variety of dimensions (sticks and planks)
ndash Hobby stores carry balsa and basswood (basswood generally denser and heavier)
ndash USA Balsa and SIG has a large assortment of wood (wwwsigmfgcom) ndash Factors to consider
bull Weightbull Strengthbull Ease of use
Wood Hands on
bull Examine the wood forndash Texturendash Grainndash Smoothnessndash Kerf marks
bull How porous is itbull How easy does a stick bendbull How much does it weigh
Sanding Balsa Wood prior to sortingSanding Balsa Wood prior to sorting
Comparison of woods
Species Wt
lbscf
StiffnessStrength
BendingStrength
CompressionStrength
Balsa 8 72 70 75
Balsa 14 156 161 149
Spruce 28 230 260 289
Basswood
26 261 288 288
Wood Characteristics
bull Anistropic means having properties that differ depending on direction
bull Wood has grain to it and will react differently depending on the grain
bull Consider how grain affects how wood reacts and build your structure with this in mind
Moisture
bull Wood absorbs moisture from the air (especially balsa wood)
bull When weight is a consideration teams may want to consider ways to remove moisture from their structure
bull Many teams try to control the moisture absorption by the wood
bull Others try to remove moisture prior to weigh in
Moisture
bull Teams may find that certain glues degrade when exposed to extreme heat(thus the structure is weaker after drying)
bull Teams should brainstorm quantify and test any techniques they consider for removing moisture from their structure
General Definitions
bull Structure
bull Column
bull Brace
bull Member
bull Stress (Forces)
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
DFW Airport - Scaffolding holding up concrete formsDFW Airport - Scaffolding holding up concrete forms
BasicConcepts
ampDefinitions
Intro to teaching basic structure
bull Wood
bull Jigs
bull Forces
bull Glue
bull Tools and More Tools
bull Construction Area
bull This yearrsquos Challenge
bull The Duct Tape Challenge
bull Summary
Construction Area
A large open table where team can place building jigs weigh wood saw and cut materials assemble amp finish structures
Cover the table top (sheet of thick plastic or masonite)Make sure that work areas are kept well ventilated especially when teams are using glues with harmful vapors
Cutting Tools and EquipmentCutting Tools and Equipment
Helping teams learnabout wood characteristics
bull Wood
ndash Wood comes in a variety of dimensions (sticks and planks)
ndash Hobby stores carry balsa and basswood (basswood generally denser and heavier)
ndash USA Balsa and SIG has a large assortment of wood (wwwsigmfgcom) ndash Factors to consider
bull Weightbull Strengthbull Ease of use
Wood Hands on
bull Examine the wood forndash Texturendash Grainndash Smoothnessndash Kerf marks
bull How porous is itbull How easy does a stick bendbull How much does it weigh
Sanding Balsa Wood prior to sortingSanding Balsa Wood prior to sorting
Comparison of woods
Species Wt
lbscf
StiffnessStrength
BendingStrength
CompressionStrength
Balsa 8 72 70 75
Balsa 14 156 161 149
Spruce 28 230 260 289
Basswood
26 261 288 288
Wood Characteristics
bull Anistropic means having properties that differ depending on direction
bull Wood has grain to it and will react differently depending on the grain
bull Consider how grain affects how wood reacts and build your structure with this in mind
Moisture
bull Wood absorbs moisture from the air (especially balsa wood)
bull When weight is a consideration teams may want to consider ways to remove moisture from their structure
bull Many teams try to control the moisture absorption by the wood
bull Others try to remove moisture prior to weigh in
Moisture
bull Teams may find that certain glues degrade when exposed to extreme heat(thus the structure is weaker after drying)
bull Teams should brainstorm quantify and test any techniques they consider for removing moisture from their structure
General Definitions
bull Structure
bull Column
bull Brace
bull Member
bull Stress (Forces)
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
BasicConcepts
ampDefinitions
Intro to teaching basic structure
bull Wood
bull Jigs
bull Forces
bull Glue
bull Tools and More Tools
bull Construction Area
bull This yearrsquos Challenge
bull The Duct Tape Challenge
bull Summary
Construction Area
A large open table where team can place building jigs weigh wood saw and cut materials assemble amp finish structures
Cover the table top (sheet of thick plastic or masonite)Make sure that work areas are kept well ventilated especially when teams are using glues with harmful vapors
Cutting Tools and EquipmentCutting Tools and Equipment
Helping teams learnabout wood characteristics
bull Wood
ndash Wood comes in a variety of dimensions (sticks and planks)
ndash Hobby stores carry balsa and basswood (basswood generally denser and heavier)
ndash USA Balsa and SIG has a large assortment of wood (wwwsigmfgcom) ndash Factors to consider
bull Weightbull Strengthbull Ease of use
Wood Hands on
bull Examine the wood forndash Texturendash Grainndash Smoothnessndash Kerf marks
bull How porous is itbull How easy does a stick bendbull How much does it weigh
Sanding Balsa Wood prior to sortingSanding Balsa Wood prior to sorting
Comparison of woods
Species Wt
lbscf
StiffnessStrength
BendingStrength
CompressionStrength
Balsa 8 72 70 75
Balsa 14 156 161 149
Spruce 28 230 260 289
Basswood
26 261 288 288
Wood Characteristics
bull Anistropic means having properties that differ depending on direction
bull Wood has grain to it and will react differently depending on the grain
bull Consider how grain affects how wood reacts and build your structure with this in mind
Moisture
bull Wood absorbs moisture from the air (especially balsa wood)
bull When weight is a consideration teams may want to consider ways to remove moisture from their structure
bull Many teams try to control the moisture absorption by the wood
bull Others try to remove moisture prior to weigh in
Moisture
bull Teams may find that certain glues degrade when exposed to extreme heat(thus the structure is weaker after drying)
bull Teams should brainstorm quantify and test any techniques they consider for removing moisture from their structure
General Definitions
bull Structure
bull Column
bull Brace
bull Member
bull Stress (Forces)
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Intro to teaching basic structure
bull Wood
bull Jigs
bull Forces
bull Glue
bull Tools and More Tools
bull Construction Area
bull This yearrsquos Challenge
bull The Duct Tape Challenge
bull Summary
Construction Area
A large open table where team can place building jigs weigh wood saw and cut materials assemble amp finish structures
Cover the table top (sheet of thick plastic or masonite)Make sure that work areas are kept well ventilated especially when teams are using glues with harmful vapors
Cutting Tools and EquipmentCutting Tools and Equipment
Helping teams learnabout wood characteristics
bull Wood
ndash Wood comes in a variety of dimensions (sticks and planks)
ndash Hobby stores carry balsa and basswood (basswood generally denser and heavier)
ndash USA Balsa and SIG has a large assortment of wood (wwwsigmfgcom) ndash Factors to consider
bull Weightbull Strengthbull Ease of use
Wood Hands on
bull Examine the wood forndash Texturendash Grainndash Smoothnessndash Kerf marks
bull How porous is itbull How easy does a stick bendbull How much does it weigh
Sanding Balsa Wood prior to sortingSanding Balsa Wood prior to sorting
Comparison of woods
Species Wt
lbscf
StiffnessStrength
BendingStrength
CompressionStrength
Balsa 8 72 70 75
Balsa 14 156 161 149
Spruce 28 230 260 289
Basswood
26 261 288 288
Wood Characteristics
bull Anistropic means having properties that differ depending on direction
bull Wood has grain to it and will react differently depending on the grain
bull Consider how grain affects how wood reacts and build your structure with this in mind
Moisture
bull Wood absorbs moisture from the air (especially balsa wood)
bull When weight is a consideration teams may want to consider ways to remove moisture from their structure
bull Many teams try to control the moisture absorption by the wood
bull Others try to remove moisture prior to weigh in
Moisture
bull Teams may find that certain glues degrade when exposed to extreme heat(thus the structure is weaker after drying)
bull Teams should brainstorm quantify and test any techniques they consider for removing moisture from their structure
General Definitions
bull Structure
bull Column
bull Brace
bull Member
bull Stress (Forces)
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Construction Area
A large open table where team can place building jigs weigh wood saw and cut materials assemble amp finish structures
Cover the table top (sheet of thick plastic or masonite)Make sure that work areas are kept well ventilated especially when teams are using glues with harmful vapors
Cutting Tools and EquipmentCutting Tools and Equipment
Helping teams learnabout wood characteristics
bull Wood
ndash Wood comes in a variety of dimensions (sticks and planks)
ndash Hobby stores carry balsa and basswood (basswood generally denser and heavier)
ndash USA Balsa and SIG has a large assortment of wood (wwwsigmfgcom) ndash Factors to consider
bull Weightbull Strengthbull Ease of use
Wood Hands on
bull Examine the wood forndash Texturendash Grainndash Smoothnessndash Kerf marks
bull How porous is itbull How easy does a stick bendbull How much does it weigh
Sanding Balsa Wood prior to sortingSanding Balsa Wood prior to sorting
Comparison of woods
Species Wt
lbscf
StiffnessStrength
BendingStrength
CompressionStrength
Balsa 8 72 70 75
Balsa 14 156 161 149
Spruce 28 230 260 289
Basswood
26 261 288 288
Wood Characteristics
bull Anistropic means having properties that differ depending on direction
bull Wood has grain to it and will react differently depending on the grain
bull Consider how grain affects how wood reacts and build your structure with this in mind
Moisture
bull Wood absorbs moisture from the air (especially balsa wood)
bull When weight is a consideration teams may want to consider ways to remove moisture from their structure
bull Many teams try to control the moisture absorption by the wood
bull Others try to remove moisture prior to weigh in
Moisture
bull Teams may find that certain glues degrade when exposed to extreme heat(thus the structure is weaker after drying)
bull Teams should brainstorm quantify and test any techniques they consider for removing moisture from their structure
General Definitions
bull Structure
bull Column
bull Brace
bull Member
bull Stress (Forces)
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Cutting Tools and EquipmentCutting Tools and Equipment
Helping teams learnabout wood characteristics
bull Wood
ndash Wood comes in a variety of dimensions (sticks and planks)
ndash Hobby stores carry balsa and basswood (basswood generally denser and heavier)
ndash USA Balsa and SIG has a large assortment of wood (wwwsigmfgcom) ndash Factors to consider
bull Weightbull Strengthbull Ease of use
Wood Hands on
bull Examine the wood forndash Texturendash Grainndash Smoothnessndash Kerf marks
bull How porous is itbull How easy does a stick bendbull How much does it weigh
Sanding Balsa Wood prior to sortingSanding Balsa Wood prior to sorting
Comparison of woods
Species Wt
lbscf
StiffnessStrength
BendingStrength
CompressionStrength
Balsa 8 72 70 75
Balsa 14 156 161 149
Spruce 28 230 260 289
Basswood
26 261 288 288
Wood Characteristics
bull Anistropic means having properties that differ depending on direction
bull Wood has grain to it and will react differently depending on the grain
bull Consider how grain affects how wood reacts and build your structure with this in mind
Moisture
bull Wood absorbs moisture from the air (especially balsa wood)
bull When weight is a consideration teams may want to consider ways to remove moisture from their structure
bull Many teams try to control the moisture absorption by the wood
bull Others try to remove moisture prior to weigh in
Moisture
bull Teams may find that certain glues degrade when exposed to extreme heat(thus the structure is weaker after drying)
bull Teams should brainstorm quantify and test any techniques they consider for removing moisture from their structure
General Definitions
bull Structure
bull Column
bull Brace
bull Member
bull Stress (Forces)
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Helping teams learnabout wood characteristics
bull Wood
ndash Wood comes in a variety of dimensions (sticks and planks)
ndash Hobby stores carry balsa and basswood (basswood generally denser and heavier)
ndash USA Balsa and SIG has a large assortment of wood (wwwsigmfgcom) ndash Factors to consider
bull Weightbull Strengthbull Ease of use
Wood Hands on
bull Examine the wood forndash Texturendash Grainndash Smoothnessndash Kerf marks
bull How porous is itbull How easy does a stick bendbull How much does it weigh
Sanding Balsa Wood prior to sortingSanding Balsa Wood prior to sorting
Comparison of woods
Species Wt
lbscf
StiffnessStrength
BendingStrength
CompressionStrength
Balsa 8 72 70 75
Balsa 14 156 161 149
Spruce 28 230 260 289
Basswood
26 261 288 288
Wood Characteristics
bull Anistropic means having properties that differ depending on direction
bull Wood has grain to it and will react differently depending on the grain
bull Consider how grain affects how wood reacts and build your structure with this in mind
Moisture
bull Wood absorbs moisture from the air (especially balsa wood)
bull When weight is a consideration teams may want to consider ways to remove moisture from their structure
bull Many teams try to control the moisture absorption by the wood
bull Others try to remove moisture prior to weigh in
Moisture
bull Teams may find that certain glues degrade when exposed to extreme heat(thus the structure is weaker after drying)
bull Teams should brainstorm quantify and test any techniques they consider for removing moisture from their structure
General Definitions
bull Structure
bull Column
bull Brace
bull Member
bull Stress (Forces)
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Wood Hands on
bull Examine the wood forndash Texturendash Grainndash Smoothnessndash Kerf marks
bull How porous is itbull How easy does a stick bendbull How much does it weigh
Sanding Balsa Wood prior to sortingSanding Balsa Wood prior to sorting
Comparison of woods
Species Wt
lbscf
StiffnessStrength
BendingStrength
CompressionStrength
Balsa 8 72 70 75
Balsa 14 156 161 149
Spruce 28 230 260 289
Basswood
26 261 288 288
Wood Characteristics
bull Anistropic means having properties that differ depending on direction
bull Wood has grain to it and will react differently depending on the grain
bull Consider how grain affects how wood reacts and build your structure with this in mind
Moisture
bull Wood absorbs moisture from the air (especially balsa wood)
bull When weight is a consideration teams may want to consider ways to remove moisture from their structure
bull Many teams try to control the moisture absorption by the wood
bull Others try to remove moisture prior to weigh in
Moisture
bull Teams may find that certain glues degrade when exposed to extreme heat(thus the structure is weaker after drying)
bull Teams should brainstorm quantify and test any techniques they consider for removing moisture from their structure
General Definitions
bull Structure
bull Column
bull Brace
bull Member
bull Stress (Forces)
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Sanding Balsa Wood prior to sortingSanding Balsa Wood prior to sorting
Comparison of woods
Species Wt
lbscf
StiffnessStrength
BendingStrength
CompressionStrength
Balsa 8 72 70 75
Balsa 14 156 161 149
Spruce 28 230 260 289
Basswood
26 261 288 288
Wood Characteristics
bull Anistropic means having properties that differ depending on direction
bull Wood has grain to it and will react differently depending on the grain
bull Consider how grain affects how wood reacts and build your structure with this in mind
Moisture
bull Wood absorbs moisture from the air (especially balsa wood)
bull When weight is a consideration teams may want to consider ways to remove moisture from their structure
bull Many teams try to control the moisture absorption by the wood
bull Others try to remove moisture prior to weigh in
Moisture
bull Teams may find that certain glues degrade when exposed to extreme heat(thus the structure is weaker after drying)
bull Teams should brainstorm quantify and test any techniques they consider for removing moisture from their structure
General Definitions
bull Structure
bull Column
bull Brace
bull Member
bull Stress (Forces)
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Comparison of woods
Species Wt
lbscf
StiffnessStrength
BendingStrength
CompressionStrength
Balsa 8 72 70 75
Balsa 14 156 161 149
Spruce 28 230 260 289
Basswood
26 261 288 288
Wood Characteristics
bull Anistropic means having properties that differ depending on direction
bull Wood has grain to it and will react differently depending on the grain
bull Consider how grain affects how wood reacts and build your structure with this in mind
Moisture
bull Wood absorbs moisture from the air (especially balsa wood)
bull When weight is a consideration teams may want to consider ways to remove moisture from their structure
bull Many teams try to control the moisture absorption by the wood
bull Others try to remove moisture prior to weigh in
Moisture
bull Teams may find that certain glues degrade when exposed to extreme heat(thus the structure is weaker after drying)
bull Teams should brainstorm quantify and test any techniques they consider for removing moisture from their structure
General Definitions
bull Structure
bull Column
bull Brace
bull Member
bull Stress (Forces)
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Wood Characteristics
bull Anistropic means having properties that differ depending on direction
bull Wood has grain to it and will react differently depending on the grain
bull Consider how grain affects how wood reacts and build your structure with this in mind
Moisture
bull Wood absorbs moisture from the air (especially balsa wood)
bull When weight is a consideration teams may want to consider ways to remove moisture from their structure
bull Many teams try to control the moisture absorption by the wood
bull Others try to remove moisture prior to weigh in
Moisture
bull Teams may find that certain glues degrade when exposed to extreme heat(thus the structure is weaker after drying)
bull Teams should brainstorm quantify and test any techniques they consider for removing moisture from their structure
General Definitions
bull Structure
bull Column
bull Brace
bull Member
bull Stress (Forces)
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Moisture
bull Wood absorbs moisture from the air (especially balsa wood)
bull When weight is a consideration teams may want to consider ways to remove moisture from their structure
bull Many teams try to control the moisture absorption by the wood
bull Others try to remove moisture prior to weigh in
Moisture
bull Teams may find that certain glues degrade when exposed to extreme heat(thus the structure is weaker after drying)
bull Teams should brainstorm quantify and test any techniques they consider for removing moisture from their structure
General Definitions
bull Structure
bull Column
bull Brace
bull Member
bull Stress (Forces)
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Moisture
bull Teams may find that certain glues degrade when exposed to extreme heat(thus the structure is weaker after drying)
bull Teams should brainstorm quantify and test any techniques they consider for removing moisture from their structure
General Definitions
bull Structure
bull Column
bull Brace
bull Member
bull Stress (Forces)
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
General Definitions
bull Structure
bull Column
bull Brace
bull Member
bull Stress (Forces)
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Stress (Forces)that act on a structure
bull Compression
bull Tension
bull Shear
bull Twisting Rotation
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Compression
Compression forces try to ldquocrushrdquo thingsCompression forces try to ldquocrushrdquo things
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Compression
Compression forces also try to buckle thingsCompression forces also try to buckle things
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Tension
Tension forces try to pull things apartTension forces try to pull things apart
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Shear
Shear forces try to ldquobreak thingsrdquoShear forces try to ldquobreak thingsrdquo
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Hands on
bull Take a 12rdquo piece of wood ndash Stand on its end and push down on it
You are putting the wood in compressionndash Now try to pull it apartndash Now lay it frac12 over the edge of your table
and press down on the outside piece
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
More DefinitionsConcepts
bull Buckling load ndash The amount of weight required to cause a
structure to fail
bull Critical Lengthndash The length where wood no longer bends
but crushes
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Law of Squares (cont)
bull If I have a 12rdquo column and a 4rdquo column constructed from the same material the 4rdquo column will hold 9 times as much weight as the 12rdquo column
bull 4rdquo = 13 of 12rdquo So Invert 13 to get 3 and then square it to get 9
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Hands OnLaw of Squares
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Balsa Balsa Estimate Weight
Balsa Actual Weight
Weight Held Estimate
Weight Held Actual
36rdquo X X
18rdquo
12rdquo
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Demonstrations
The next few slides come from a computer program that allows a user to build a structure on screen and then test
the structure We are using screen shots form this program to demonstrate
a few of these concepts
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Simple 4 column 8rdquo tall structure with compression loadSimple 4 column 8rdquo tall structure with compression load
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Held 110 grams of weightHeld 110 grams of weight
11074 grams
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Simple Tower ndash horizontal braces in middleSimple Tower ndash horizontal braces in middle
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Tested to failure 4 x 110 = 440 gramsTested to failure 4 x 110 = 440 grams
44468 grams
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Columns are now braced twice (13 length)Columns are now braced twice (13 length)
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Tested to failureTested to failure
89923 grams
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Not testing to failureNot testing to failure
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Adding another force acting on the side of the structure (only 1 gram)Adding another force acting on the side of the structure (only 1 gram)
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Disaster strikesDisaster strikes
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Correcting the problemCorrecting the problem
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
The Diagonal Braces kept the structure stableThe Diagonal Braces kept the structure stable
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Bracing
bull Horizontal Bracingndash Typically ndash horizontal bracing is used to
resist buckling in a column
bull Diagonal Bracingndash Typically ndash diagonal bracing resists twisting
in the structure (adds stability)
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
With compression force applied straight down ndash column held 3505 grams With compression force applied straight down ndash column held 3505 grams
3505 grams
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
4 x 35 = 1404 x 35 = 140
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Total Column height is 12rdquo Total Column height is 12rdquo
14038 grams
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Cutting
bull Cut (donrsquot ldquosquashrdquo) the wood
bull Cutting can damage cells at end of the piece
bull Think of ways to keep that from happening
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Cut by rocking blade straight back and forthCut by rocking blade straight back and forth
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Helping teams learn about glue characteristics
bull Gluendash Expose team to many different types of glue
read directionsbull Hot gluebull Super glue
ndash CYANOACRYLATE (pronounced sigh-ano-ack-relate) adhesive specially formulated to meet the tough demands of building and flying model airplanes Available in three different viscosities Each viscosity has different application and cure characteristics
bull Wood glue (Gorilla glue)bull Epoxybull Carpenterrsquos wood glue (Elmerrsquos)
ndash Factors to considerbull Strengthbull Drying timebull Weightbull Ease of use
Provide Adequate Ventilation
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Airplane Glue
Gorilla Glue
Glass Surface to build on
Wood Glues
CA ldquoSuperrdquo Glues
Acetone
Extra CA Glue Tips
Old Razor - to clean glass
Pill bottles to clean CA Glue Tips
GluesGlues
Contact Cement
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Glue Testing Device
bull Teams may want to construct testing devices to test the different types of glues
bull Plans for a device for testing glue strength are available at
httpwwwspecializedbalsacomstrength_test_instructionsphp
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Glue Safety Rules
bull No Horseplay
bull Read and Follow Safety Instructions
bull If you canrsquot use it safely ndash donrsquot use it
bull Donrsquot mix glues together
bull If using CA Glue ndash keep Acetone on hand
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Tools amp Safety
bull Tools such as saws X-acto knives and razors can be used to cut wood When any sharp tool is used sharp edges should always be directed away from flesh
bull Let team members experiment with cutting sawing and sanding wood with various tools Encourage them to explore any tool they think will allow them to build bettereasier
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Useful tools
bull X-acto fine tooth razor sawbull Plastic holder holding a single edge razor blade
bull small aluminum mitre box for razor saw
Other useful building itemsbull Flat tile or mirrorbull Building squarebull Emery boards sand paper
All tools should be readily available to consumers and of the teamrsquos own choosing
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
LevelStraight Edge
Levels are usually used to see if a surface is perfectly level (meaning it wonrsquot tilt up or down) They can also be used to draw a straight edge
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Other Useful Things to Have
bull Gram scale accurate to 01 gramsndash Permits weighing wood and completed
structuresndash Ohaus has a low-cost one (lt$90) but
you can probably borrow or get access to one (school lab workplace post office police station (ask for confiscated scales)
ndash Ebay frequently has ldquodealsrdquo
bull Hair Dryerndash Speeds up glue dryingndash Removes excess moisture from wood
(weight)
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
More Useful Things to Havebull Structure Tester
ndash TM or other parents are allowed to construct a tester for the team
ndash Instructions are available (httpwwwfarnorthdiorgTRAININGHow_to_build_testerdoc)
ndash Try borrowing a tester
bull Weightsndash Olympic style (2 inch hole)
flat metal weights
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Clear Plastic Ruler comes in handy when yoursquore cutting sticks of balsa wood When you mark the balsa wood make sure of three things One make sure that you have the edge of the ruler aligned with the edge of the stick Two make sure you mark the length with a single dot Otherwise if you mark it with a line it will be crooked for sure Three once yoursquove measured it be sure to measure it again There is an old woodworking saying ldquoMeasure twice cut oncerdquo Thatrsquos because it is a lot easier to fix a mistake before you make it than afterwards
Woodworking Basics
Measuring Tools
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Woodworking Basics
Measuring Tools
Top T square is used to put one piece of wood at a right angle to another
Bottom L Square
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Woodworking Basics
Measuring Tools
bull A combination square is used to mark a line lengthwise down the middle of a long piece of wood A combination square consists of two main parts The first part is a foot long metal ruler with a notch at the end to hold a pencil The second part is an adjustable steel bar that slides This lets you adjust where you want the mark to be
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Jigs
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Jig (template)
bull A gauge pattern or mold used as a guide to the form of a piece being made
bull Jigs can be 2 dimensional or 3 dimensional
bull It is not necessary to use a Jigbull A Jig helps you to build consistentlybull ANY jigs used by the team must be
BUILT by the team
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Sample materials that can be used to make templatesSample materials that can be used to make templates
Aluminum Square Tube from hardware store
Plastic and brass square tube from Hobby store
Steel keystock from hardware store
1x1 from lumber yard
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
This Yearrsquos ChallengeE The Inside DImension
If walls could talkhellip
Educational Focus Architectural Design StructuralEngineering Construction Research Innovationand Design Process Mathematics Theater Arts
Teamwork
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
AAAAHHHHHHH
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Inside DImensionStructure Specification Details (applies to both structures)
ndash 7 12rdquo le height above tester surface le 9rdquo
ndash Combined wt of both structures le 140 grams
ndash Weight difference between 2 structures le 20 grams
ndash fits over 2rdquo cylinder
ndash Any wood allowed as long as it is just natural wood (no plywood laminates composites coatings)
ndash Glue may only be used as an adhesive
ndash Glue may not extend beyond frac14rdquo of a joint
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Closeup of a Tester
bull Base alone
bull Loaded with structure presser board amp weights
Presser BoardPresser Boardsupported supported about 1rdquoabout 1rdquoaboveabove
corner postscorner postsbyby
structurestructure
The Presser Board amp weights are fully supported by structureThe Presser Board amp weights are fully supported by structure
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Tester setup
Team Designed Structures
Floor surface
Metal Weights
Traditional Tester Supporting Blocks
Pressure Board
75rdquo to 9rdquo
2nd structure inside first structure
Top of red tape is 1rdquo below top of pole
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
More Hands on
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
The Duct Tape ChallengeFocus The Testing process for structure challenges
Architectural Design Structural Engineering Construction Teamwork
The Destination Where This Challenge Will Take You
bull One of the keys to building REALLY strong structures is to spend the time lsquofollowing through on the detailsrsquo Without doing so could turn a wonderfully constructed structure into a lsquoleaning tower of Pisardquo unless it is checked to be sure it is ldquoplumbrdquo
bull The process of placing weights on the structure is an area many first-time structure teams do not give sufficient attention
bull What happens if all the parts of the structure that have to carry ldquoloadrdquo do not actually contact the upper and lower surfaces of the tester What happens when the weights are placed on the structure Is there a way to anticipate those things and plan for them
bull This goal of this challenge is to help teams anticipate these questions and develop a team plan Teams that plan practice and brainstorm issues in advance will have a plan ndash and a contingency plans- so they donrsquot have to make ldquosnap decisionsrdquo at tournament that they might regret
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
bull Your team will
bull 1048720 Build and test a Structure made completely of Wood and Tape 1048720 bull Time Limit The team must complete the solution on site within one hour which will include weigh-in and testing of the
structure bull Team Materials Required Teams will provide their own duct tape and masking tapes and may prefer to bring a ruler for
their use The pre-cut balsa wood for the structure a ldquotemplaterdquo and ldquojigrdquo gram scale for weighing it testing device and Olympic weights will be provided by the Trainers
bull Roadmap for Success Teams must work together and plan a strategy in order to successfully solve this Challenge bull a Team will open kit and construct the structurebull b When complete they can raise their hand and let the Trainer know they are ready for ldquoweigh-inrdquo bull c The team will test the strength of their Structure by stacking weights on the Pressure Board of a Structure Tester while
the Structure rests on the Tester Basebull d The testing will result in an Official Weight Held Normally at each level of competition the Structures with the highest
Official Weight Held score will receive 160 points The score for all other teams in that Level would be based on the percentage of that Official Weight Held for that competition Level In this challenge the focus is not on the weight held but on how well the teams can place the weights on their structure so that it will hold as much weight as possible
bull Building the Structures Specificationsbull a A ldquolevel playing fieldrdquo has been ensured for all teams in regard to the design and the materials of the structure The
test here will be in how they construct and TEST the structure bull b Height of Structures Each Structure must have a minimum height of 75in (191cm) and a maximum height of 8 in
(219cm)bull c Weight of Structures The weight for Middle and Secondary team Structures may not exceed 40 grams The
weight for all other levels is unlimited but the teams will want to know what it is for their records and to note the efficiency of their structure
bull d The Structures are designed to support weights stacked on the Pressure Board of the Structure Tester bull e The Structures must have an opening running their entire height which can accept a circular column with an outside
diameter of 2in (51cm) The Structure must rest upon the Tester Base and fit over the Safety Pole The Structure must fit entirely on the Tester Base and may not touch any of the Safety Supports or the Safety Pole
bull f The Structures will be constructed using ONLY natural Wood and Tape- Duct tape and Masking Tape no other materials will be allowed The Balsa Wood included in the kit was not weighed in advance and has not been screened in any way Pieces were placed randomly in the kits
bull Laminates in the Structures Team may use duct tape as a laminate in this structure but should realize it will add to the weight of the finished product
bull Jig provided is a simple block of wood with L square
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Weight Placement
bull Practice practice practice
bull Have a plan
bull Be prepared to modify your plan
bull What will happen when you mishandle a weight
bull How can you protect your fingers from being pinched
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Analyzing
bull Analyze broken structure to determine what failed
bull Use safety shields and watch what happens ndash make notes
bull Analyze the video tapes
bull Use a sports camera
bull Incremental testing
Analyzing tested structures is the best way to discover where you can improveAnalyzing tested structures is the best way to discover where you can improve
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Design Considerations
bull Record pertinent information about every structurendash Glues usedndash Materials usedndash Weight and weight held
bull Donrsquot change too many variables between tests
Donrsquot change too many things at onceDonrsquot change too many things at once
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Whatrsquos the Secret
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Thoughts onthe Tournament
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Tournament Day Considerations
bull How are your going to transport your structure safely to tournament
bull What supplies do you need for repairs
bull What will you store your structures in when you turn them over to the Appraisers
Tournament Day ThoughtsTournament Day Thoughts
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
(continued)
bull Before tournament do your own mock check in with the structure ndash does it meet the challenge specifications
bull Do you think you need a spare structure
Tournament Day ThoughtsTournament Day Thoughts
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Closing Thoughts
bull Good structures look good
bull Keep it simple
bull Keep in Level
bull Keep it Well-glued
bull Have Fun
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Questions
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
Good Luck
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-
AcknowledgementsVictor Tom Bill Allen Pre-engineering Corp (pictures) Reggie Bunis
Ernie Chang
Special thanks to Charles Compton Arlington TX for creating the structure of this presentation and offering
suggestions corrections technicalexplanations and commentary
- Tester setup
-