UTAH VALLEY UNIVERSITY
and
ENGINEERING GRAPHICS & DESIGN TECHNOLOGY
present
3D DESIGN DERBY 2009
INSTRUCTIONS, RULES, AND INFORMATION
David Manning
11/7/2008
TABLE OF CONTENTS
DESCRIPTION .................................................................................................................................2
PURPOSE .......................................................................................................................................2
ELIGIBILITY .....................................................................................................................................2
ENGINEERING ASPECT ....................................................................................................................2
SCHEDULE OF DEADLINES AND EVENTS ...........................................................................................2
CAR REQUIREMENTS ......................................................................................................................3
HELPFUL HINTS...............................................................................................................................3
WHEELS, AXLES, & HUBS.................................................................................................................4
BUILDING CARS ..............................................................................................................................4
DOCUMENTS ..................................................................................................................................5
AWARDS & PRIZES .........................................................................................................................5
DEDUCTIONS & DISQUALIFICATION ................................................................................................6
HIGH SCHOOL INSTRUCTOR RECOMMENDATIONS ..........................................................................6
APPENDIX A – WHEEL/AXLE/HUB DETAILS ......................................................................................7
APPENDIX B – CAR BASE DATA........................................................................................................8
APPENDIX C – CAR INSPECTION BOX & TRACK DETAIL .....................................................................9
APPENDIX D – WEIGHT COMPARTMENTS...................................................................................... 10
APPENDIX E – PREVIOUS CAR DESIGNS ......................................................................................... 11
APPENDIX F – SAMPLE DRAWINGS................................................................................................ 12
APPENDIX G – CHECKLISTS ............................................................................................................ 13
1
UVU/EGDT 3D DESIGN DERBY 2009
DESCRIPTION
The Utah Valley University Engineering Graphics & Design Technology department sponsors a yearly
competition for area high schools involving design, modeling, drawing, building, and racing model cars.
The competition is designed to test a student’s ability to conceptualize a model car design, produce a
virtual 3D model using constraint-based modeling software, configure each design to accommodate
standard parts, size and weight limitations, track dimensions, etc., manufacture a car, and race it against
others. Points are awarded for marketing illustrations, detail drawings, and speed. Winners receive
awards and/or trophies.
PURPOSE
The purpose of the competition is to allow high school students to engage with UVU in learning and
applying engineering, design, 3D modeling, and prototyping skills in a fun and competitive setting. It also
helps EGDT with recruiting and promotion, and solidifies the high school/university relationship.
ELIGIBILITY
Any high school may submit entries as long as it is able to transport contestants to UVU on race day.
Registrations must be received by the application deadline to compete. EGDT reserves the right to limit
the number of contestants to a manageable number as necessary. If such limitation is imposed, entries
will be accepted on a first come first served basis, or numbers will be limited by some other announced
restriction. All documentation must be received by the deadline specified herein or announced in updates
through email or on the website to be awarded design/drawing points. Cars must be properly designed
and built according to all rules and regulations, and both car and designer must be present on race day to
be awarded race points. Points awarded in different areas determine winners in different categories,
such as best design, best drawings, fastest car, etc.
ENGINEERING ASPECT
All mechanical engineering projects must accommodate design criteria and constraints, i.e. a designed
part of any complexity must allow for the use of standard manufacturing processes, standard fasteners,
must mate with other parts, and must function appropriately within the bounds of its intended purpose. To
that end, derby car entries must accommodate design requirements for size, shape, weight, and the use
of standard wheels and axles in order to function properly against other cars and in harmony with the
racetrack. Cars that do not conform to these constraints are not considered viable even if the design
looks good or the car is fast. In addition, certain “best practices” should be followed if one wishes to
produce a fast car. This contest allows entrants great flexibility to demonstrate creativity and design
skills, while forcing conformity to design constraints. It is a typical, if simplistic, engineering problem.
SCHEDULE OF DEADLINES AND EVENTS
The following deadlines and dates shall apply to all submittals for the 2009 competition:
Registration Wednesday, March 18 3:00 p.m.
Car model files to EGDT Dept. (if printed at UVU) Wednesday, April 15 3:00 p.m.
Drawings and Rendering to EGDT Dept. Wednesday, April 22 3:00 p.m.
Cars printed, assembled, painted, and weighed Monday, May 4 (see requirement #6, pg. 2)
Racing at UVU Tuesday, May 5
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CAR REQUIREMENTS
All cars in the 3D Design Derby will conform to the following specifications. Entries not conforming to
these specifications will be disqualified from racing or receiving other awards or prizes. See appendix G.
1. Car size shall not exceed 7” long, 3” wide, and 3” tall in finished state with wheels and axles
attached. Size/shape limits will be checked by inserting cars into a no-go box (see appendix C).
Cars that cannot enter the box cleanly and completely will be disqualified.
2. Final car weight, after all assembly, painting, and added weight shall not exceed five (5) ounces
as measured by EGDT scales. All cars will be weighed by EGDT personnel before racing. No
contestant will be allowed to handle his/her car after official weigh-in and inspection.
3. Only wheels, axles, and hubcaps supplied by EGDT may be used. All four wheels must be used.
Axles are one-piece, and axle lengths shall not be altered (no axle splitting).
4. Cars shall contain an accessible, closeable compartment for adding or removing weight (see
appendix D). No external weights, and no weight that is taped, glued, or otherwise “stuck” on the
car is allowed. No tools should be required to add or remove weight.
5. Axle channels shall be undercut to facilitate removal of support material (see appendix B).
6. No car shall be allowed to race with wet or tacky paint.
7. Cars shall include the assigned contestant number embossed or engraved into the car itself, as
part of the printed model, and shall be clearly visible and readable.
8. Car design, with wheels in place, shall conform to the track cross-section so as to clear the
central track rail and remain sufficiently centered to avoid interfering with cars in adjacent lanes.
This requirement will be checked with the no-go box (see appendices B and C).
9. Axle/wheel lubrication shall be limited to silicone spray (which leaves a dry coating) or to any dry
lubricant powder such as graphite. No oils, liquids, WD-40 type sprays, etc. are allowed.
Keep in mind that design constraints represent the engineering aspect and critical experience of the
competition. Non-conformance to specifications and rules negates the value of the derby, and will result
in disqualification.
HELPFUL HINTS
Experience shows that some “best practices” increase chances of success and help avoid mistakes and
mishaps. The following items are offered for the consideration of all instructors and contestants.
Both instructors and contestants should read these rules and guidelines thoroughly before
modeling cars and consult them during and after the process.
Car weight should be as close to five ounces as possible without going over to maximize speed.
Weight should be easily added or removed in small increments, such as BBs or coins, to make it
adjustable. Cars should be near final weight before coming to the race and need little or no
adjustment at official weigh-in. EGDT is under no obligation to supply weights at the race.
Cars should be finished well before race day so they can be altered, if necessary, and so that
paint can dry thoroughly before racing.
All car dimensions should be double checked and verified by instructors to avoid disqualification.
No-go boxes may be printed and used at high schools to ensure that car size/shape limits
conform to regulations. Remember that layers of paint can affect overall car size and weight.
Cars should have “noses” that provide bearing surfaces for starting gates.
If using silicone spray lubricant, do NOT allow it to touch ABS plastic car bodies. Silicone (or its
spray propellant) and ABS build material are not chemically compatible, and damage to the car
will result. Silicone will not damage axles or wheels.
Cars may be one-piece parts or assemblies of many parts. Remember that detail drawings must
be submitted and judged, and drawing sets that are most detailed and complete will receive
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higher marks. Again, every car should at least have two parts, a body and a weight compartment
door of some type (see appendices D and F).
Use large openings to access weight compartments so weight can be adjusted easily. Small
orifices, tubes, etc. are cumbersome, as they require weight to be changed one piece at a time.
Cars should not incorporate very thin sections or very acute angles. These features will break off
or be damaged. For example, if a car is designed with windows, it may be better to engrave or
recess them than to remove them completely, leaving only thin supports between them.
Car base width between wheels should not exceed 1.70 inches (1.65 is better) to ensure that
wheels, after being assembled with axles and hubs, can still turn freely against the car body (see
appendix B). Bases that are too wide interfere with wheels after hubcaps are installed.
Recommended axle hole diameter is 0.10 inch. This allows axles to slide in the holes while
providing a slight interference to keep them in place.
Study dimensions of axles and wheels carefully. Wheels must turn freely to race properly.
Powder lubricants are messy. They will quickly soil cars and the track. Use them sparingly.
Liquid lubricants are BAD. They collect dust and debris, and ultimately slow cars down. They are
not allowed (see requirement #9).
Weight compartments should have sufficient volume to hold necessary weight. If using BBs,
compartments should have a minimum volume of 1.0 cubic inch. Other types of weight may
require other compartment volumes. Undersized compartments are BAD. Oversized are OK.
EGDT uses Citizen model CT1200 scales for race weigh-in, purchased from Old Will Knott
Scales, costing approximately $180 each. They are high accuracy instruments capable of
measuring to the nearest .005 oz. You are encouraged to purchase a similar scale for pre-race
weighing, or cars can be brought to the EGDT department prior to race day for preliminary
weighing. All cars, whether previously weighed or not, will be officially weighed immediately
before racing. Make sure cars are near final weight before coming to race. Bring your own
weights! EGDT is not responsible to provide weight.
Dimensions shown in figures herein are not controlled by EGDT and may vary by unknown
amounts. Allow clearance where appropriate to avoid conflicts between car body and other parts.
Any contestant who wishes to do something “strange” or “different” with his/her design should
contact EGDT to ensure compliance with design specifications and guard against disqualification.
The vertical curve in the track, where it transitions from sloping to level, has a radius of
approximately 46”. Designs should allow the front and rear of cars to clear the track as they
traverse the radius.
WHEELS, AXLES, & HUBS
Only wheels, axles, and hubs supplied by the EGDT department are allowed. All cars MUST use the
same wheel/axle/hub assemblies, in their intended configurations, with all four wheels used. Wheels and
axles may be polished or sanded if desired, but their basic shapes and functions cannot be altered.
Dimensional information is supplied in appendices A and B for car design purposes.
BUILDING CARS
All car model files must be saved in “.STL” format (“File/Save Copy As” option) at high resolution for
3D printing. Use the “sparse fill” option to conserve material. Printing time ranges from five to twelve
hours, depending on the design, and dissolving support material requires one day. Priming and painting,
axle or wheel treatments, adding weights and weighing, and assembly also require time. Please plan
accordingly. Remember that no external weight “stuck” on the car will be allowed. For painting, a
primer coat be applied first to seal the pores in the plastic. Paint adds weight and increases size
dimensions. Schools that own printers may print their own cars. Others may be printed at UVU or another
location with a printer by making arrangements with the appropriate person. Only .STL files should be
transferred to other locations for printing to ensure that model files cannot be altered.
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DOCUMENTS
Detailed drawings and rendering must be received in the EGDT department (CS-704) on or before the
deadline specified in the schedule herein or any revised schedule distributed later than this document.
Detailed drawings should contain separate A or B-size drawings of each part of the car (body, weight
compartment door, and any other separate parts). Drawings should display all views, dimensions, and
notes required to define parts for manufacture or to allow someone else to create a 3D model of the car
from the drawings. The rendering should show artistic views of the car suitable for marketing it to a client.
All detail drawings must clearly display the contestant number in the title block, but should not
show the contestant name or school. All drawings for one car must be stapled in the upper left corner
or bound together in the proper order for submittal for judging. See appendices F & G.
AWARDS & PRIZES
Prizes will be awarded at the conclusion of the competition in room CS-404 or another room specified on
race day. The top twenty winners have the option to leave cars at UVU for display at the Technology
Expo in the McKay Events Center that evening for public viewing. Points will be awarded according to
the following criteria:
Detail Drawings (CAD plots) . . . . . . . 50 points
Complexity (use of advanced modeling features, weight compartment) . 10
Creativity . . . . . . . . 10
Layout (standard views and projection, sections, detail views) . . 10
Dimensions and notes . . . . . . . 10
Appearance (line types and contrast) . . . . . 10
Rendering . . . . . . . . 10 points
Artistic Value/Presentation . . . . . . 5
Use of media (print paper, use of other media programs) . . . 5
Racing Speed . . . . . . . . 40 points
PLACE POINTS PLACE POINTS PLACE POINTS PLACE POINTS
1st 40 6th 30 11th 20 16th 10
2nd 38 7th 28 12th 18 17th 8
3rd 36 8th 26 13th 16 18th 6
4th 34 9th 24 14th 14 19th 4
5th 32 10th 22 15th 12 20th 2
TOTAL POSSIBLE . . . . . . . 100 POINTS
Drawings shall be submitted in a packet with rendering on top, followed by body detail and then by any
other detailed drawings. A ten-point deduction will be made when this format is not followed.
Prizes will be awarded for fastest car, best drawings, and best in show. Additional prizes for other
categories may be awarded at the discretion of the EGDT department. These are determined by the
judges and are independent of other scores.
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DEDUCTIONS & DISQUALIFICATION
DEDUCTIONS - The following are grounds for deduction of points from total scores:
Drawings out of order or missing from document packets
Failure to follow instructions from this document or as given by EGDT department.
DISQUALIFICATION - The following are grounds for disqualification from racing or winning awards:
No contestant number visible on car and/or drawings
Any means of propulsion other than gravity. Cars must free-wheel
Lack of internal weight compartment
Using external weights
Using a car made or raced in a previous year or made by someone else
Exceeding size, shape, or weight limits
Not using standard wheels, axles, and hubcaps; or not using them as intended
Wet paint on race day
Incorporating anything lewd, suggestive, or pornographic into models or drawings
Failure to follow instructions from this document or as given by EGDT department.
Failure to respect UVU facilities and faculty, i.e. engaging in vandalism, littering, horseplay, etc.
HIGH SCHOOL INSTRUCTOR RECOMMENDATIONS
High school instructors can be extremely valuable resources to derby contestants. EGDT believes that
participation in the 3D Derby can serve to promote and strengthen high school programs and high
school/university relations. It is recommended that high school teachers be involved in the derby to
whatever extent their time allows. Here are a few ways that teachers can help student competitors:
Build a car. This helps the teacher explore the program and makes it easier to help students
Encourage sketching and brainstorming. Students should explore what they want the car to
look like, then find ways to make the program work to create that concept. This encourages
exploration of deeper program functions and promotes learning. Determining the car design by
forcing it to conform to functions one already knows is not an effective way to learn new skills.
Provide oversight. Become involved with contestants and provide helpful criticism and
information. Check their progress often. Review this document and any updates with them.
Ensure contestants do their own work. Each model should reflect the ability and creativity of
the designer. Help may be given, but each contestant should “own” his/her own work.
Check designs. Problems with weight, size, or other factors that manifest on race day can be
eliminated by instructors who regularly check contestant progress. Instructors should be familiar
with all rules and recommendations and ensure that students know them also. This will reduce or
eliminate deductions and disqualifications and provide a better experience for all involved.
Communicate with EGDT when questions arise.
Encourage experimentation. Print mock car bases to test car/wheel/axle assemblies. Promote
a paradigm of self checking and developing one’s own best practices and optimal design ideas.
Display cars and trophies in high school drafting departments.
Discuss race day etiquette. Make sure contestants know how to behave while at UVU. In the
past, there have been problems with litter, BBs and drink bottles strewn about, throwing things,
playing tag, wandering off, and not following instructions. EGDT faculty don’t enjoy dealing with
behavior problems or staying late to clean up messes. Contestants are visitors and should act
like adults and clean up after themselves. Please see last disqualification item above.
6
APPENDIX A – WHEEL/AXLE/HUB DETAILS
7
APPENDIX B – CAR BASE DATA
UNDERCUT FOR EASE
OF REMOVAL OF
SUPPORT MATERIAL
FROM AXLE HOLES
8
APPENDIX C – CAR INSPECTION BOX & TRACK DETAIL
All cars qualify for judging and racing by meeting size, shape, and weight requirements. Size and shape
are verified by placing the car in a “no-go” inspection box. Box details are shown below.
Box model files are available from EGDT, in .STL format, at no cost for all interested high school
programs. Boxes are available for sale from EGDT at a cost of $175.00 each. It is recommended that all
participating high schools print or obtain their own inspection boxes and scales to verify car eligibility
before coming to
the race. Boxes
should be printed
lying sideways with
hinge holes oriented
vertically for best
results.
9
APPENDIX D – WEIGHT COMPARTMENTS
Every car is required to have an internal or hidden weight compartment. It should have a volume of at
least 1.00 cubic inches, but the size may vary depending on the type of weight used, including BBs,
pinewood derby lead weights, fishing weights, tungsten plugs, coins, etc. The weight compartment must
have a door that allows for weight to be added or removed quickly without tools. Some examples of
weight compartments and doors are shown here:
10
APPENDIX E – PREVIOUS CAR DESIGNS
Previous car designs are included here for reference only. Note that cars manufactured or raced in
previous years or copied from previous designs will be disqualified.
11
APPENDIX F – SAMPLE DRAWINGS
Every effort should be made to produce accurate, complete, high quality drawings of car bodies and
parts. Correct projection, use of auxiliary views, sections, details, etc., enhances drawings. At least three
documents are required; rendering, car body detail, and weight compartment door detail. Other car parts,
if any, should also be detailed. A or B size only. The following are samples provided for reference.
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APPENDIX G – CHECKLISTS
The following checklists are provided for your convenience in preparing to compete in the derby. They
are not intended to be comprehensive, and do not eliminate the need to comply with requirements listed
in this document.
CAR CHECKLIST
□ Car size within limits – 7” Long X 3” Wide X 3” Tall
□ Car weight <= 5 ounces
□ Design accommodates standard wheels, axles, and hubcaps
□ Weight compartment with door included
□ Axle channels undercut
□ Dry paint
□ Embossed/engraved contestant number
□ Conforms to track cross-section shape and vertical curve
□ Proper lubrication used
DOCUMENT CHECKLIST
□ One A or B size marketing rendering
□ One or more A or B size car body detail drawing(s)
□ One or more A or B size weight compartment door detail drawing(s)
□ Other A or B size car part detail drawings (if applicable)
□ Drawings stapled or bound in correct order
□ Assigned contestant number shown on all documents
□ Drawings submitted on or before deadline
□ No school or personal information on drawings
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