can you guess what is inside of this box? how can a designer show on a drawing what is hidden from...
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Can you guess what is inside of this box?Can you guess what is inside of this box?
How can a Designer show on a drawing what is hidden from view?
If you had the Invisible Women’s powers you could make the box invisible and see what is hidden from view.
This is done by using the technique of drawing…
SECTION VIEWSSECTION VIEWS
A Section Drawing of a V-Type Four Stroke Diesel Engine
Section Views: Section Views: are used to show inside features of objects that would otherwise be unseen.Section Views: Section Views: are used to show inside features of objects that would otherwise be unseen.
The Unit OrganizerLAST UNIT/ Experience
Basic DimensioningCURRENT UNIT
PRODUCE SECTION VIEW DRAWINGSNEXT UNIT/ Experience
Auxiliary Views
Techniques used on Working Detail Drawings
The Big Picture
1. What determines the need for a section view?2. What are some types of section views?3. How are webs, ribs and spokes represented in a section view? And why?
UN
IT S
ELF-
TEST
Q
UES
TIO
NS
UN
IT RELATIO
NSH
IPS
Have many
types
Are
Labe
led
by
When
omittedSection Views
Inside feature are not visible
Types of Section Views
C.P.L. Elements & Placement
Principles & Exceptions
Section Lines (X-Hatch)
Are identified by
Required When
Hand out Unit organizers
LAST UNIT/ Experience
Basic DimensioningCURRENT UNIT
PRODUCE SECTION VIEW DRAWINGSNEXT UNIT/ Experience
Auxiliary Views
2-col note vocab
Hand-outs
worksheets
Jeopardy Game
Drawings
Quizzes
Unit Test
The Unit Organizer
UNIT SCHEDULE
Section ViewsInside feature are not visible
Types of Section Views
C.P.L. Elements & Placement
Principles & Exceptions
Section Lines (X-Hatch)
Techniques used on Working Detail Drawings
The Big Picture
1. What determines the need for a section view?2. What are some types of section views?3. How are webs, ribs and spokes represented in a section view? And why?
UN
IT S
ELF-
TEST
Q
UES
TIO
NS
UN
IT RELATIO
NSH
IPS
Have many
types
Are
Labe
led
by
Are identified by
When
omitted
Required When
ObjectivesObjectives• Explain why section views are necessary. • Explain and accurately draw a cutting- plane line
and X-hatch (cross-hatch) lines.• Recognize and appropriately use the following
section view types on a drawing: Full sectionFull section, Half sectionHalf section and Offset sectionOffset section.
Section Views:
Section Views: are used to
show inside features
inside features of objects that
would otherwise be unseen.
Section Views:
Section Views: are used to
show inside features
inside features of objects that
would otherwise be unseen.
Why Use Section Why Use Section Views?Views?
How can we dimension to these interior features without using the hidden lines?
ANSIstandard
Thick line
Thick line
JIS & ISOstandard
Thin line
CUTTING PLANE LINESTYLESCUTTING PLANE LINESTYLES
Viewingdirection
Viewingdirection
Viewingdirection
This course
SECTION LININGSECTION LININGSection lines or cross-hatch lines are used to
indicate the surfaces that are cut by the cutting
plane.
Sectionlines
Drawn with thin dark lines usually at a 45 degree angle45 degree angle.
SECTION LINES SYMBOLSSECTION LINES SYMBOLS
The section lines are different for each of
material types.
Cast iron,Malleable iron
Steel Concrete Sand Wood
For practical purposes, the cast iron symbol is
used most often for any materials.
SECTION LINING PRACTICESECTION LINING PRACTICE
The spaces between lines may vary from .125125 inches
for small sections to .25 .25 inches for large sections.
COMMON MISTAKE
SECTION LINING PRACTICESECTION LINING PRACTICE
Section lines should notshould not be drawn parallel or
perpendicular to contour of the view.
COMMON MISTAKE
FULL SECTION VIEWFULL SECTION VIEWThe view is made by passing the straightstraight cutting
plane completely through the entire part.
HALF SECTION VIEWHALF SECTION VIEWThe view is made by passing the cutting plane halfway
through an object and removing a quarter of it.
HALF SECTION VIEWHALF SECTION VIEWA center line is used to separate the sectioned half
from the unsectioned half of the view.Hidden lines are omitted in the unsectioned half of the view.
OFFSET SECTION VIEWOFFSET SECTION VIEWThe view is made by passing the bended cutting
plane completely through the part.
Do not show the edge viewsof the cutting plane.
The Unit OrganizerLAST UNIT/ Experience
Basic DimensioningCURRENT UNIT
PRODUCE SECTION VIEW DRAWINGSNEXT UNIT/ Experience
Auxiliary Views
2-col note vocab
Hand-outs
worksheets
Jeopardy Game
Drawings
Quizzes
Unit Test
UNIT SCHEDULE
Section ViewsInside feature are not visible
Types of Section Views
C.P.L. Elements & Placement
Principles & Exceptions
Section Lines (X-Hatch)
Techniques used on Working Detail Drawings
The Big Picture
1. What determines the need for a section view?2. What are some types of section views?3. How are webs, ribs and spokes represented in a section view? And why?
UN
IT S
ELF-
TEST
Q
UES
TIO
NS
UN
IT RELATIO
NSH
IPS
To show the inside features of mech. parts
•Full section•Half section•Offset section •Line types
•Arrows•Labeling
•Surfaces•Direction•Spacing•Angle•Material specifications
Required When
Have many
types
Are
Labe
led
by
Are identified by
When
omitted
ObjectivesObjectives• Recognize and appropriately use the
following section view types on a drawing: Removed sectionRemoved section, Revolved Revolved sectionsection and Broken-out sectionBroken-out section.
• Explain how hidden lines are used in section views.
• Accurately draw RibsRibs, WebsWebs, SpokesSpokes and LugsLugs in section views.
Example : Revolved vs. removed sections.
Revolved section Removed section
REMOVED SECTION VIEWREMOVED SECTION VIEW
Example : Situation that removed section is preferred.REMOVED SECTION VIEWREMOVED SECTION VIEW
PreferredPoor
Too messy !!
Example : Multiple removed section viewsREMOVED SECTION VIEWREMOVED SECTION VIEW
A
A
B
B
SECTION A – A
SECTION B – B
REVOLVED SECTION VIEWREVOLVED SECTION VIEW
Basic concept
Given
Step 1
a. Assign position of cutting plane.
b. Draw axis of rotation in front view.
Steps in construction
REVOLVED SECTION VIEWREVOLVED SECTION VIEW
Edge view of Edge view of cross-sectioncross-section
Steps in construction
Given
a. Transfer the depth dimension to
the front view.
REVOLVED SECTION VIEWREVOLVED SECTION VIEW
Step 2
Steps in construction
Given
REVOLVED SECTION VIEWREVOLVED SECTION VIEW
a. Draw the revolved section.
Step 3
b. Add section lines.
Steps in construction
Given
REVOLVED SECTION VIEWREVOLVED SECTION VIEW
FINAL PICTURE
Placement of revolved section
1. Superimposed to orthographic view.
SuperimposedBreak
2. Break from orthographic view.
REVOLVED SECTION VIEWREVOLVED SECTION VIEW
The view is made by passing the cutting plane normal
to the viewing direction and removing the portion of an
object in front of it.
BROKEN-OUT SECTION VIEWBROKEN-OUT SECTION VIEW
EXAMPLE : Comparison among several section techniques
The Unit OrganizerLAST UNIT/ Experience
Basic DimensioningCURRENT UNIT
PRODUCE SECTION VIEW DRAWINGSNEXT UNIT/ Experience
Auxiliary Views
2-col note vocab
Hand-outs
worksheets
Jeopardy Game
Drawings
Quizzes
Unit Test
UNIT SCHEDULE
Section ViewsInside feature are not visible
Types of Section Views
C.P.L. Elements & Placement
Principles & Exceptions
Section Lines (X-Hatch)
Techniques used on Working Detail Drawings
The Big Picture
1. What determines the need for a section view?2. What are some types of section views?3. How are webs, ribs and spokes represented in a section view? And why?
UN
IT S
ELF-
TEST
Q
UES
TIO
NS
UN
IT RELATIO
NSH
IPS
To show the inside features of mech. parts
•Full section•Half section•Offset section•Removed section•Revolved section•Broken-out section•Aligned section
•Line types•Arrows•Labeling
•Surfaces•Direction•Spacing•Angle•Material specifications
Required When
Have many
types
Are
Labe
led
by
Are identified by
When
omitted
TREATMENT OF HIDDEN LINESTREATMENT OF HIDDEN LINES
Hidden lines are normally omitted from section
views.
The Unit OrganizerLAST UNIT/ Experience
Basic DimensioningCURRENT UNIT
PRODUCE SECTION VIEW DRAWINGSNEXT UNIT/ Experience
Auxiliary Views
2-col note vocab
Hand-outs
worksheets
Jeopardy Game
Drawings
Quizzes
Unit Test
UNIT SCHEDULE
Section ViewsInside feature are not visible
Types of Section Views
C.P.L. Elements & Placement
Principles & Exceptions
Section Lines (X-Hatch)
Techniques used on Working Detail Drawings
The Big Picture
1. What determines the need for a section view?2. What are some types of section views?3. How are webs, ribs and spokes represented in a section view? And why?
UN
IT S
ELF-
TEST
Q
UES
TIO
NS
UN
IT RELATIO
NSH
IPS
To show the inside features of mech. parts
•Full section•Half section•Offset section•Removed section•Revolved section•Broken-out section•Aligned section
•Line types•Arrows•Labeling
•Surfaces•Direction•Spacing•Angle•Material specifications
Ribs, Webs , Spokes, hidden lines & dimensions
Required When
Have many
types
Are
Labe
led
by
Are identified by
When
omitted
RIBS AND WEBSRIBS AND WEBS
RibsRibs and WebsWebs are thin, flat features of an object used for
bracing or adding strength.
RibsRibs and WebsWebs are thin, flat features of an object used for
bracing or adding strength.
Rib RibWeb
EXAMPLE : RIB
Normal multiview drawing
Normal section view
Section view drawing with convention
EXAMPLE : WEB : flatwise cut
Normal multiview drawing
Normal section view
Section view drawing with convention
EXAMPLE : WEB : crosswise cut
EXAMPLE : WEB : multiple section view
Rim
SpokeSpoke:: One of several bars
attaching a hub to the rim of a wheel
Spoke
Spoke
Rim
HubHub
SPOKESSPOKES
EXAMPLE : SPOKE
Misleading impression
Lug:Lug: An ear-like projection used for attachment.Lug:Lug: An ear-like projection used for attachment.
LUGSLUGS
Lug:Lug: An ear-like projection used for attachment.Lug:Lug: An ear-like projection used for attachment.
LUGSLUGS
EXAMPLE : LUG
CONVENTIONAL PRACTICE
Omit the section lines on the section view of
Rib, Web and Lug, if the cutting plane is
passed flatwise through.
Spoke, if the cutting plane is passed longwise
through.
Aligned Section
ObjectivesObjectives• RXxxXXx
• XxxxxxxxxxxxxxxxXxxx
• X xxx xxxxxxxxxxxx
DEFINITION
Aligned section is a section view that is drawn
by imaginary rotating the object’s features
appeared in a principal view about symmetry
axis
Example : Hole
Gives the impression that this
holes are at unsymmetrical
position.
Example : Hole
Example : Rib
Example : Ribs & Holes
Example : Aligned section of keywayExample : Spoke & Keyway
Example : Lug
Conventional Break
CONVENTIONAL PRACTICE
For long objects that have to draw in a small
scale to fit them on the paper, it is recommended
to remove its long portion (which contains no
important information) and draw the break lines
at the broken ends.
SCALE 1:1
Example
Example
SCALE 2:1
STANDARD BREAK LINES
Rectangularcross section
Wood
Metal
Cylindricalcross section
Tubularcross section
TO DRAW CYLINDRICAL BREAK
R
R/3 R/3
30o
30o
800
TO DIMENSION A BROKEN PART
Typicaldimensioning
method
16
not to scale dimensions
16
800
