Group 9St Francis xavier universityAPRIL 4TH 2015

The E-Z PlateRethinking the Barbell

Final ReportPrepared by: Tristan Martel, Caitlyn Peddigrew, Simon Pellerin, and Michael Scarth

Prepared for: Dr. Emeka Oguejiofor and Mr. Paul Doiron

April 1st, 2016

St. Francis Xavier University 3034 Physical Science CentreAntigonish, Nova Scotia BOH 1X0

Subject: Letter of Transmittal

Dear Dr. Emeka Oguejiofor and Paul Doiron,

The members of group 9 are pleased to present our report The E-Z Plate for academic credit in the course Design and Communications II. This report addresses the concerns regarding the loading and unloading of weight-lifting plates on to a barbell that is resting on the ground and the implementation of a new design.

As active citizens who benefit from the services provided at recreational facilities we feel there is need for improvement in the design of standard weightlifting plates. Weightlifting plates have been designed to easily slide on to the collars of barbells that are elevated on a rack. This design is insufficient when loading and unloading a barbell that is on the floor because the perimeter of the plate is subject to friction from the ground as the weightlifter attempts to slide the plate onto the barbell. Therefore our goal regarding the design and implementation of The E-Z Plate is to improve an athlete’s workout by removing the deficiencies associated with the loading and unloading of weightlifting plates on to a barbell that is resting on the ground. Following several meetings with the Senior Machinist and Design Technician of STFX, Steven Macdonald, the design of our plate was re-evaluated and improved to enhance the efficiency of our final product.

The formulation of this report was a valuable and rewarding experience as it brought with it many challenges that enhanced our engineering skills in strength of materials, problem-solving, and graphics and design. As aspiring engineers we hope that we have presented a detailed description and sufficient model of our design so as to fully aid the understanding of the problem and our solution.

If you have any furthers questions or concerns regarding our design, please contact one of the group members.

Best Regards,

Michael Scarth Tristan Martel Simon Pellerin Caitlyn Peddigrew

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Table of Contents

LETTER OF TRANSMITTAL 2

LIST OF ILLUSTRATIONS 4

EXECUTIVE SUMMARY 5

ABSTRACT 6

1.0 INTRODUCTION 6

1.1 TERMINOLOGY 61.1.0 GENERAL WEIGHT LIFTING TERMINOLOGY 71.1.1 OUR DESIGN TERMINOLOGY 7

1.2 PROJECT DESCRIPTION 7

2.0 THE PROJECT PHASES 8

2.1 INITIATION PHASE 8

2.2 PLANNING PHASE 8

2.3 EXECUTION PHASE 122.3.0 CARDBOARD PROTOTYPE 122.3.1 MACHINING A PROTOTYPE 132.3.2 DESIGNING THE FINAL PROTOTYPE 15

2.4 CLOSING PHASE 19

3.0 PRODUCTION AND COST 19

4.0 RECCOMENDATIONS 21

5.0 CONCLUSION 21

REFERENCES 23

APPENDIX A 24

APPENDIX B 25

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List of Illustrations

CONCEPT A 9

CONCEPT B 9

CONCEPT C 9

CONCEPT D 9

MODIFIED CONCEPT C 10

CARDBOARD PROTOTYPE 12

MACHINED PROTOTYPE 13

PROTOTYPE CONTRAST 15

LOADING SCENARIOS 17

DEFLECTION EQUATION 18

SHEAR STRESS EQUATION 18

CENTROID EQUATION 19

APPENDIX A 24A.1 BARBELL DIAGRAM 24A.2 COMPONENT LABELS25A.3 PLATE DETAIL26A.4 SLIDER DETAIL 27

APPENDIX B 28B.1 BARBELL DIAGRAM 28B.2 MASS AND CENTROID CALCULATIONS 29

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Executive Summary

Professional athletes and frequent gym users are constantly putting themselves at

an unnecessary risk for injury due to the inefficiency associated with the design of

standard weight lifting plates. Group 9 has set forth a goal to re-engineer the standard

weight lifting plate so as to provide enhanced efficiency when loading and unloading a

barbell that is resting on the ground. This report provides insight into the design and

implementation of The E-Z Plate as developed by the members of Group 9 for our term

project in Design and Communications II.

Standard weight lifting plates are designed so that they can easily slide onto the

collar of a barbell that is elevated on a rack. The problem associated with this design is

that the perimeter of the plate is subject to friction from the surface when the user is

attempting to slide a plate onto a barbell that is resting on the ground. This can put the

user at risk for injury because they are required to partially lift the barbell off the ground

with one hand while simultaneously sliding the weight on to the collar with the other.

This can lead to back problems and is overall an inefficient process for users. As various

exercises that require the loading and unloading of barbells on the ground become

increasingly popular, the current design of the standard weight lifting plate has become a

prominent problem.

We determined a new way to design the standard weight lifting plate so as to

eliminate the deficiencies associated with the loading and unloading of plates onto the

collar of a barbell that is resting on the ground. Our design uses a sliding locking

mechanism that changes how the plate can be loaded or unloaded from the barbell. After

consultation with Paul Doiron of the AH Roy & Associates team, our group was able to

narrow our design down to one concept of the five possibilities we had considered. After

further consultation with Steven Macdonald, Senior Machinist and Design Technician at

STFX, the implementation of the proposed locking mechanism on a 10-lb plate was

achieved. The physical 10-lb model only accounts for the performance of the locking

mechanism. Proper calculations and re-designing of the standard 25 kilogram weight

were performed on a virtual model to display the proposed re-modeling that would need

to be done if our design were to be carried out for production.

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ABSTRACTThe standard weight lifting plate is designed to easily slide onto the collar of a barbell

that is elevated on a rack. This design is inadequate for exercises that require loading to

occur on the ground as the perimeter of the plate is subject to friction from the surface

and therefore puts a strain on users. This report describes a redesign of the weight lifting

plate to make the process of loading barbells on the ground more efficient. The design

consists of an enlarged whole and a sliding locking mechanism. The sliding locking

mechanism is built to support the loading of 25-kilogram plates and is simple to use. We

recommend the design to be implemented into new gyms and targeted towards highly

trained athletes.

1.0 INTRODUCTIONThe aim of The E-Z Plate project is to improve the design of a standard weight lifting

plate by removing the deficiencies associated with the loading and unloading of plates

onto the collar of a barbell that is resting on the ground. This report presents designs of

the various concepts our group considered, a description of the design and analysis of the

operational efficiency of each, and the necessary calculations. The E-Z Plate is aimed at

the upper end of the market and is suitable for experienced athletes and weight lifting

trainees.

1.1 TERMINOLOGYThis report includes terminology that describes various aspects of weight lifting and the

equipment used. To avoid confusion the following sections use visuals and descriptions

to assist in understanding these terms.

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1.1.0 GENERAL WEIGHT LIFTING TERMINOLOGYThe barbell refers to the bar that is used in various weight lifting exercises. The barbell

collars are the ends of the bar in which the plates are loaded onto (see appendix A.1). The

plates come in standard sizes depending on their weight and can vary in mass distribution

and material.

1.1.1 OUR DESIGN TERMINOLOGYThe sliding/locking mechanism is the term used to address the machined component that

slides within the curved cutout in the plate and then locks once in place. The sliders refers

to the two curved steel pieces that make up the sliding mechanism. The slider rods are the

individual steel rods that connect the two curved pieces together. The handle refers to the

protrusion on one of the sliders and the indentation on the opposing side is the groove in

which the plates will fit together in when stacked (see appendix A.2).

1.2 PROJECT DESCRIPTIONThe standard weight lifting plate has been designed to easily slide on to the collar of a

barbell that is elevated on a rack. The problem associated with this design is that the

perimeter of the plate is subject to friction from the ground as the user attempts to slide

the plate onto the collar of the barbell. To avoid this problem, users are required to lift the

partially loaded barbell off the ground with one hand while simultaneously trying to slide

additional plates (up to twenty five kilograms each) onto the collar with the other. This is

difficult to perform and produces a risk for injury. Currently, barbell jacks have been

used to elevate the bar a few inches of the ground. Jacks have helped reduce the problem,

however they are expensive, bulky and many public gyms do not have them.

There are many exercises that require the barbell to be loaded on the ground, some of

which include the deadlift, snatch, and the clean and jerk. These exercises have become

increasingly popular for both the average gym enthusiast and professional athlete and

therefore the inefficient loading process has become a more prominent problem. The E-Z

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Plate is designed to eliminate this problem by improving the efficiency of the plate while

still maintaining the standard weight of the current existing plates.

Five concepts were discussed and analyzed to assist in the development and

implementation of our final product.

2.0 THE PROJECT PHASESThe goals Group 9 set forth at the beginning of the design project were constantly

addressed throughout the various stages of the project. These goals included creating a

product that was efficient, durable and low in cost. In doing so we were able to

successfully invent a new design of the standard weight lifting plate that reduces the

problem associated with the loading and unloading of plates on to the collars of barbells

resting on the ground. The phases of the project are broken down into their component

tasks and displayed on the Gantt Chart (see Appendix B.1). The following sections

outline the steps taken to create our final product.

2.1 INTIATION PHASEDuring the initiation phase of the project, our group met to discuss and brainstorm

possible ideas and problems that are encountered in our everyday life. The problems were

analyzed and possible solutions were considered. Group 9 narrowed down the range of

ideas based on feasibility, complexity and general interest in the subject matter. Once the

conclusion was made on the design project, we met with Dr. Emeka Oguejiofor to discuss

our ideas and get the design approved.

2.2 PLANNING PHASEDuring the planning phase the main focus was on determining the best design approach to

re-engineer the standard plate so that it could easily slide onto the collar of a barbell on

the ground. The original design, dubbed Concept A, which was presented during the

individual proposals, consisted of a pin mechanism and an elongated hole in which a

plate could be dropped onto the collar of a barbell and be locked in (see Concept ‘A’ on

the next page). Concept B resulted from a small adjustment in the design of Concept A

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(see Concept ‘B’ on the next page). By eliminating the extension of the inner hole to the

outer perimeter of the plate, Concept B would reduce the impacts the design has on the

mass balance and center of mass. Concept C eliminated the horizontal pin mechanism

and replaced it with a curved locking mechanism as we felt the horizontal pin mechanism

was impractical and less efficient (see Concept ‘C’ below). In addition, the curvature

increased the surface area the barbell has in contact with the sliders, dispersing the force

acting on the sliders. The main challenge with Concept A, B and C was that the designs

were non-symmetrical and therefore posed a problem because standard weight lifting

plates are designed so as to have a center of mass at the middle of the collar hole because

when on a barbell they need to have the ability to rotate freely around the bar. Concept D

originated as a solution to this problem, as it consisted of a spinning locking mechanism

and ensured full symmetry (see Concept ‘D’ below).

*Note: Dimensioned in millimeters

Having Concept A, B, C and D as a foundation for the design project a meeting was

scheduled with Paul Doiron of the A.H. Roy & Associates team. Mr. Doiron assisted in

helping determine which concept would be most feasible. He also suggested a list of

criteria Group 9 would need to assess in order to successfully design a more efficient

weight lifting plate. These included overcoming safety problems and keeping costs of the

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design and assembly low in order to be competitive.  Following the meeting with Mr.

Doiron, Group 9 met to analyze the designs and discuss other alternatives. Concept D

was discarded as a possible solution due to the complexity of the system and the

difficulty associated with ensuring the strength and safety of the plate when locked into

its static position. Concept C was concluded to be the most sufficient design, however

many adjustments were made along the course of the execution phase and are discuss

later in greater detail. Originally the locking mechanism was intended to only move along

a quarter circle. It was decided that by extending the cut out to a half circle, the overall

design would be more symmetrical and would assist with maintaining the mass balance

about its center (see Modified Concept ‘C’ below). It should be noted that the following

modified concept includes the letters “E-Z” and the “25 kg” however these are aesthetic

and will only be painted on following the production of the plate.

After making the necessary conclusions regarding Concept C, a meeting was scheduled

with the Senior Machinist and Design Technician at STFX, Steven Macdonald. Steven

provided the group with practical feedback with regards to material selections, feasibility

of construction for the locking mechanism and the possibility of constructing a model or

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prototype for testing and presentation. The following recommendations were made

during the meeting:

I. Cast Iron should be used for the main construction of the plate, however;

II. Cast iron is a difficult metal to machine; therefore intricate or moving parts

should be constructed from another material that is easier to work with (ie.

Stainless Steel);

III. Before settling on a custom-made locking mechanism, consider making use of

available stock parts, namely the ‘hitch pin’ or ‘clevis pin’;

IV. Constructing a full size (25 kg) prototype may not be possible with the resources

available in the machine shop, instead;

V. Standard 10-lb plates could be modified to incorporate the proposed locking

mechanism on a smaller scale.

Following the meeting with Steven, Group 9 met to discuss the new information and

decide upon the best way to proceed. The discussion concluded that:

I. Cast iron is a commonly-used material for the construction of weightlifting plates

and would be well-suited for our project;

II. Using stainless steel in the locking mechanism would help reduce friction and

improve overall efficiency of the product;

III. The ‘hitch pin’ and ‘clevis pin’ suggested for review would be insufficient to

replace the locking mechanism currently proposed, but could possibly be

incorporated to work in conjunction with the proposed mechanism;

IV. A full size (25 kg) prototype is not necessary to complete the project

V. The 10-lb model will be sufficient to display and test the proposed locking

mechanism.

In conjunction with the 10-lb model which only accounts for implementation of the

locking mechanism, we rendered a 3-D model (see Appendix A) to display the work that

would be done on the actual standard plate if our design were to be carried out for

production. The plate design is discussed further later on in the report.

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2.3 EXECUTION PHASEUpon completion of the planning phase, all of the necessary decisions had been made to

allow Group 9 to proceed into the execution phase. The execution phase has two main

components; producing a physical prototype, and completing the detailed design for The

E-Z Plate concept.

2.3.0 CARDBOARD PROTOTYPEAn obstacle that had to be overcome when brainstorming the various concepts was trying

to visualize the prototype in three dimension. This created a level of uncertainty and

confusion within the design stages. In order to understand these concepts and confirm

their feasibility, a cardboard prototype was built (see Cardboard Prototype below). The

prototype assisted the group in understanding the function of the locking mechanism.

Cardboard Prototype

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2.3.1 MACHINING A PROTOTYPE Group 9 initially intended to produce a full-scale prototype to showcase the results of the

detailed design for the final presentation. However, after consultation with Steven

MacDonald, the purpose of the prototype was modified to simply demonstrate the

function of the proposed locking mechanism. Therefore correct dimensioning and

calculations were not necessary for the machining of the prototype. As a result, Group 9

was able to machine the prototype before center of mass calculations were done for the

full-size 25 kg plate. The resulting prototype features the designed locking mechanism

retrofitted into a standard 10 lb plate (see Machined Prototype below). The dimensions

used in the construction of the prototype were selected with the primary goal of creating

the best visual representation of the proposed locking mechanism, given that the

prototype is less than one quarter of the size of the 25 kg plate being designed. During

this stage, regular updates were made with Steven in order to address any concerns or

changes that needed to be made.

Machined Prototype

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The first step in the construction of the 10 lb plate was to determine the dimensions for

the slots that Steven had to cut to allow for maneuvering of the locking mechanism.

Group 9 wanted to have the locking mechanism curved in order to dissipate the force

acting on the sliders over a greater surface area. It was important to make sure the

mechanism was not machined too tight in the plate because this would render it unable to

slide easily due to the friction between the collar of the bar and the sliders. After proper

dimensioning was done, Group 9 supplied Steven with the information needed to produce

the main cut out of the 10 lb plate. The curve cut out where the sliders would be guided

needed to have a large enough arc length so that when sliding the collar of the barbell

through the plate it would not prevent the locking mechanism from sliding into position.

It was originally planned to create the locking mechanism with three slider rods. After

consulting with Steven it was decided that two slider rods would be more efficient

because it reduced the friction in the locking mechanism and provided enough strength

on their own. However due to the size difference, this alteration was not continued with

the full size 25 kg plate. The largest change that occurred via consultation with Steven

was to have the slider rods extend the entire length between the sliders, instead of

welding them just on the outside. The reason for this decision was to reduce the amount

of parts needed to design the locking mechanism. Originally the final design would have

had three slider rods, two sliders, one handle and extra machining on one of the sliders. It

was decided to extend one of the slider rods through the slider to provide a handle on one

side. On the opposing side an indentation was made to allow for the plates to fit together

when stacked. This helped reduce the amount of parts needed in the locking mechanism

as well as the amount of machining that needed to be done. Another contribution Steven

had suggested and incorporated into the design of the locking mechanism was the peg

(see fig #). The peg is used to stop the slider mechanism from travelling the full length of

the half-circle cut out. Although the locking mechanism can only be maneuvered along a

quarter circle path, the full half-circle cut out creates symmetry and assists in helping

calculate the centre of mass. To machine a 90 degree edge is not feasible, and as shown

from the contrast between the machined plate and the cardboard plate our design evolved

from having hard corners to rounded ones (see Prototype Contrast on the next page).

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Prototype Contrast

2.3.2 DESIGNING THE FINAL PROTOTYPEThe detailed design of the 25 kg plate consisted of determining dimensions and material

selections for each component to effectively support applied forces, have a total mass of

25 kg, and precisely locate the center of mass. In previous reports, moment of inertia was

mentioned as a property that would be considered during the detailed design. Upon

further review, it was determined that there is no true standard moment of inertia for

these plates, as plate models currently in use have wide variations geometry and mass

distribution. It was also mentioned previously that the full-size plate would be built to a

weight of 45 lbs. Since then, our research has indicated that Olympic and other high-

performance athletes lift standardized metric masses. It was then decided that our model

would be a 25 kg plate rather than the previously described 45 lb plate.

Weight Lifting standards list 450 mm and 53 mm (International Powerlifting Federation,

2015) as standard dimensions for the outer diameter of the plate and the diameter of the

center hole respectively. Aside from these two parameters, all other dimensions were to

be determined during the detailed design. This left far too many variables for analysis so

a few dimensions were chosen to facilitate ease of use and create the desired look and

feel. These dimensions were:

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30 mm thickness for both the inner disk and the outer ring

5 mm thickness for each of the sliders

Gray ASTM 20 Cast Iron Alloy was material selected for the construction of the plate.

This material was chosen because it is a standard material for use in the construction of

weightlifting plates, and was also recommended during a consultation with Steven

MacDonald. The slider is fabricated from a number of small components that must be

precisely constructed and assembled. Steven (in the same consultation) suggested that

these pieces be built from a strong but workable metal, as cast iron is too brittle for such

small and precise components. Stainless 304 Steel Alloy was selected for use in the slider

components.

Since the most complicated geometry, including arc segments, are located in the center of

the plate, the first dimensions to be determined were the ones involved in the locking

mechanism.

The length of the slider was required to span the diameter of the center hole (53 mm)

with a reasonable overlap on either side of the center hole (approximately 10 mm). The

overlap region is necessary to support the forces applied to the slider.

To determine the size of the slider cross-section necessary to support the applied forces,

there were two main loading scenarios to consider (see Loading Scenarios on the next

page). The first involving the slider supporting the weight of the bar, under the force of

gravity. In this case, the mass of the bar (25 kg) is distributed over no less than 4 sliders

(one plate on either end of the bar, with two sliders on each plate). The maximum loading

scenario, however, occurs when the plate is lifted by the bar and rotates into an upside

down position, such that the plate’s mass (25 kg) is supported by the two sliders over the

bar. Both of these loading scenarios cause primarily shear forces in the slider. The ideal

method of analysis would have been to use the a shear stress calculation with the yielding

stress of the selected stainless steel material, with a factor of safety, to find the necessary

cross-section (and therefore height, given the 5 mm width). However, the material

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properties listed in the back of the statics textbook did not include a value for the yielding

shear stress for the selected stainless steel material, so that analysis was not an option.

Loading Scenarios

Instead, Group 9 opted to use a beam deflection calculation, representing the slider as a

simply-supported beam with a 53 mm span, the weight due to the 25 kg mass equally

divided between the two endpoints and a single support in the middle of the beam.

Allowing a maximum deflection of 0.1 mm in the equation shown (see Deflection

Equation below), the height term within the moment of inertia expression (for the slider

cross-section) could be determined. This analysis revealed that the slider height had to be

only about 3 mm for the allowed deflection. However, this does not consider either shear

stress, or the functionality of the sliding mechanism. Since the slider component must be

fast and easy to grab and move, it was decided that a height of 15 mm (rather than 3 mm)

would be used. For assurance, the same applied force was run through the shear stress

equation (see Shear Stress Equation below) with the proposed slider cross-section. This

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calculation returned a stress of about 1.6 MPa. While there was no listed shear yielding

stress for Stainless 304 Steel Alloy, the tensile and compressive yielding stress were 207

MPa. While it can’t be proven with certainty, the difference between the shear stress and

the tensile/compressive yielding stress provides a reasonable confidence in the strength of

the proposed cross-section.

Deflection Equation Shear Stress Equation

The remaining dimensions had to be determined such that the desired mass and centroid

could be achieved. AutoCAD and Microsoft Excel were used extensively in the

remaining portion of the analysis. The face of the plate was drawn out in AutoCAD with

dimensions being tentatively chosen based on the appearance of the plate. Each

geometric region on the face of the plate was listed on the Mass & Centroid Calculations

spreadsheet (see Appendix B.2). Each area was determined using AutoCAD’s “list”

command and entered in the spreadsheet. The corresponding thickness for each region

was entered in the next column, which allowed for calculation of the volume of each

region. The density of the material for each region was then listed in the next column

(negative densities were assigned to void spaces), which allowed for the calculation of

the mass of each region. A summation of each regional mass gave the total mass of the

plate, which would automatically update with any subsequent dimensional revisions. The

x- and y-coordinates for the centroid of each region were entered in the next two

columns. Most of these centroids were trivial to locate as the regions were circular or

simple composite shapes, however a number of regions were modelled as arc segments

which required manual centroid calculations using the formula listed in the Dynamics

textbook (Meriam, 2015). Products were then taken of the mass with each of the

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individual x- and y-centroid locations. Sums of these products were taken for use in the

centroid formula (see Centroid Equation below) as given in the statics textbook

(Hibbeler, 2014). This formula was used to calculate the x- and y-coordinates of the total

center of mass. Lastly, three flexible parameters (thickness of the intermediate fill, radius

of the balancing circle, and the y-coordinate of the centroid of the balancing circle) were

adjusted using a trial-and-error method until the total mass reached 25.0000 kg and the

mass was centered with 0.0001 mm precision. This level of precision plays a significant

role in designing a high quality product, as was named as a major goal in this project.

Centroid Equation

A complete set of dimensioned and labelled orthographic and pictorial drawings for the

plate and locking mechanism (see Appendix A.3 & A.4) can be found in at the end of the

report.

2.4 CLOSING PHASEDuring the closing phase, the focus shifted to completing the necessary details in order to

present the final product. This included revising and formatting the AutoCAD drawings,

and using them to generate a 3D model to help display the final design. In this phase,

Group 9 decided to develop a logo to establish an identity and uniformity among works

(i.e. print, graphics, web, and presentations). The closing phase also included the

preparation of the final presentation.

3.0 PRODUCTION AND COSTThe industry norm for other high end weight plate companies like Eleiko and Ivanko is to

outsource and produce their cast iron plates in places like china where it can be achieved

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at a much lower cost. In casting iron, the best way to do so is through the process of sand

casting. Sand casting is done by imprinting wet sand with the design and shape of your

desired product and pouring the molten iron into the casting. Some plates are currently

produced in the USA, however they are low quality and not for the target demographic

Group 9 is intending to sell to. With this in mind, Group 9 would aim to outsource in

producing the cast iron plate in order to keep up with our competition. From an

engineering company in China, a rough estimate for the pouring, finishing, packaging

and delivering of a 25 kg standard shape would cost around $50 Canadian (Cast Iron

Price Calculator, n.d.). These plates would then have to be shipped to Canada in order to

be assembled with the locking mechanism. In machining the sliders and slider rods, it

would be preferable to do so in Canada. Machining in large quantities can be done very

easily and based on industry standards for machining stainless steel, the cost for each

locking mechanism would be around 70 cents Canadian (CUSTOMPART.NET, 2009).

In order to assemble the locking mechanism onto the plate, labourers and welders would

be needed to finish the construction. Other companies selling high end and highly exact

weight plates sell at around the $250 price range and can go upwards of $325 per plate.

Because this plate will be breaking norm in the industry, Group 9 will look to sell the

plate at a relatively low profit margin in order to keep the costs down. Group 9 hopes to

produce The E-Z Plate at a cost of $60 for raw material production, casting and

machining, $100 for shipping and taxes and finally $20 for assembly, labour and welding

for a grand total of $180. At a 20% profit, The E-Z Plate would sell for $216 Canadian

and would be a very attractive option in the market due to the added ease of use, while

costing less than a plate that does not include the loading assistance that The E-Z Plate

provides. A large aspect of production that Group 9 will be tending to is the quality

assurance from the foundries that the cast iron is coming from. Group 9 will not accept

any imperfect plates produced, this includes look, size and weight, for this creates a large

concern in the fitness industry, where one can go to a gym and weigh a 20 kg plate only

to find it is actually 18 or 22 kg. This is what creates the market for the high quality and

exact plates that Group 9 will produce.

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4.0 RECOMMENDATIONSA few recommendations should be considered if The E-Z Plate were to be produced for

the market. An efficient production system would need to be established to reduce the

cost of production and maximize profits. The E-Z Plate targets customers who will expect

the highest quality plates which are easy to use, durable, and precisely designed and built.

It is of the utmost importance that the quality of the plate is not compromised, as a result

of low-quality fabrication processes.

The design could also be incorporated into different types of weightlifting plates. There

are different types of cast iron and bumper plates used for specific exercises and

competitions. Powerlifting and Olympic Weightlifting plates are high quality plates that

are growing in popularity. Most of the exercises using these plates involve loading a

barbell on the ground, and could therefore benefit from implementing The E-Z Plate

design. No significant changes would have be made to the Powerlifting and Olympic

Weightlifting plates due to the simplicity of their design and geometry. Implementing the

mechanism developed for The E-Z Plate into other plate types would expend the market

and make The E-Z Plate solution available to a broader variety of athletes.

5.0 CONCLUSIONThe E-Z Plate design eliminates the deficiencies associated with loading and unloading

plates onto a barbell, resting on the ground. Although this report only includes the design

specifications for the standard 25 kilogram plate, the principles can be incorporated into

all standard sizes of weight lifting plates. It is expected to cost about $180 per unit to

produce The E-Z Plate commercially, which includes materials, shipping, casting,

machining and taxes. Group 9 plans to generate a 20% profit, resulting in a competitive

retail price of $216 for an easy to use and high quality plate.

This comprehensive design project came with a wide variety of responsibilities that

challenged our skills in various engineering courses including statics, strength of

materials, graphics and design. We were forced to think critically and apply the

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knowledge and skills we have developed over the course of our studies at St. Francis

Xavier University to a real-life problem. It was rewarding to work as a team and

successfully engineer a solution to the deficiencies associated with loading and unloading

weight lifting plates, which the members of Group 9 felt needed to be addressed. In

summary, the goals initially established by Group 9 were to create a product that is easier

to use than the current standard plates on the market, is durable, and competitive in cost.

Group 9 has achieved these goals with the design of The E-Z Plate, as it has proven to

provide a more efficient loading process, can resist the stresses of weightlifting, and is

high in quality. Group 9 is proud to present this final edition of The E-Z Plate.

Electronic copies of this report and all previous works associated with The E-Z Plate

project are available on our website:

http://people.stfx.ca/engr/DesignProjects/2016/Group9/

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References[1] Cast Iron Price Calculator. (n.d.). (DANDONG FUDING ENGINEERING MACHINERY

CO., LTD) Retrieved March 2016, from Dangdong Foundry: www.iron-foundry.com/cast-iron-price-calculator.html

[2] CUSTOMPART.NET. (2009). Retrieved March 2016, from Cost Estimator:        www.custompertnet.com/estimate/machining/

[3] R.C. Hibbeler, Statics & Mechanics of Materials (Fourth Edition). Pearson Prentice Hall, 2014.

[4] J.L. Meriam, Engineering Mechanics Dynamics (Eighth Edition). John Wiley & Sons Inc., 2015.

[5] International Powerlifting Federation. (2015, December 10). Technical Rules.Retrieved from Inernational Powerlifting Federation: http://www.powerlifting-ipf.com/rules/technical-rules.html

[6] Lincir, T. (2001). National Fitness Trade Journal Magazine. The Making Of A Perfect        Olympic Plate , 24-26.

23

Appendix AA.1

24

A.2

25

A.3

26

A.4

27

28

Appendix BB.1

29

B.2

30