Car Specifications REVISION DATE: 2/15/2017 6:01:00 PM Basic instructions on how to make a pushmobile can be found in the Bear book. The wooden pushmobile can be built in a few den/pack meetings. The cost should be around $40 from scratch, and reuse of scrap wood and supplies can reduce the cost. A sample pushmobile model is at the end of this document, and there are many other models available. Search the web, look for examples of other models. Pre-made pushmobiles may be exempt from some of the dimensions and other specifications, since the cars were already in place. The safety measures (e.g. no exposed screws) still remain in effect. Note: A cubmobile is slightly different than a pushmobile. A cubmobile is a single-rider racer with a mandatory handbrake, the car is more for downhill racing. A pushmobile is for a team of Scouts, has a handle in the back for running and stopping, an optional handbrake, and is a flat-level racer only. We will be racing pushmobiles for this Derby. Materials: Factory-manufactured chasses are not permitted. Go-cart frames, shopping cart bases, lawnmower decks or similar items are not permitted. The car must be made of wood. Metal frames, bicycle handle bars, and items like it will not be allowed. Also, consider woods like whitewood or pine. They are cheaper and lighter than oak, cherry, etc. Fasteners may be metal (bolts, screws, etc). Bolts and nuts are the first choice, followed by screws. Nails are not permitted. They do not hold the car together with the wear and tear they will receive, and they will vibrate loose. Motors or engines are not permitted. The cars are Scout-powered. No batteries. If your car comes with electrical decoration (lights), the battery must be disconnected and removed. Dimensions: Width: A minimum of 24 and a maximum of 48 wide. A wide wheelbase assures the car will not flip over on turns. Length: The length of the centerboard MUST NOT exceed 84. Height: The handle SHOULD be made appropriate for the height of the boys pushing. The seat MUST be attached directly to the centerboard. It keeps the center of gravity low, so the car does not flip over on turns. Construction: Safety glasses must be worn by the Scouts and Adults when operating any tool. A good life-long practice. Note: The BSA national does not encourage use of power tools until around age 18. Scouts must take part to build and assemble the cars. This is half the fun!
Scouts MUST be patient with their leaders, follow the assembly instructions, and accept guidance from the adult leaders. Adults should able to ensure the safety and proper assembly of the car. Frame: The centerboard (frame) must be (minimum) 2x4 wood. 2x3 is not sturdy enough for the rigors of racing. 2x6 and wider is allowed, but makes the car heavier. There should be at least 1 ½ clearance from the bottom of the frame to the ground. (Recommended) For cars used by the younger Scouts, a piece of plywood screwed to the bottom will provide some comfort for the boys. Wheels & Tires: The car must have exactly four wheels. Two wheels in the front, and two wheels in the back, on both sides evenly. All four wheels must touch the ground at the same time. The wheels MUST be between 4 and 15 in diameter, counted from edge to edge of the tire. The wheels MAY be pneumatic/inflatable, plastic or rubber. Plastic wheels can be used on inside tracks; rubber wheels may leave marks on the floor The wheelbase must be 30 or more, axle to axle. Provides stability to the car. No motors, engines or any other power sources to aid in the car s mobility are allowed. The car must be Scoutpowered via the push handle. Push Handles: You must add a push handle to the back. This will be the ONLY part of the car that the pushers are permitted to touch during a race. The push handle must be sturdy enough to safely push the car and stop the car. The post connecting the handle to the car must be made of wood. The handle itself may be wood or plastic. Steering: The car must have front-wheel steering. The car must be steered with one (or more) of the following: o Rope The Scout must have a safe place to keep their feet. o Foot petals The Scout must be able to reach the steering board. o Hard-steering wheel attached to the front steering rod. Safety blocks must be applied to the steering rod, to prevent flip over on turns. 3/8 to ½ should do fine to provide a safe turning radius. Driver: The car must have a seat. The seat must have a solid backrest.
The seat MUST be within 2 of the centerboard. This keeps the driver safe with a low center of gravity and will not be top-heavy. For younger Scouts, you should consider a foot rest. A small panel screwed to the bottom of the centerboard will do. It will prevent younger Scouts from potentially getting their feet wedged. Decorating: Enjoy, and be creative! As long as any accessories are not interfering with the driver or pushers, that would be fine. You may put a number on your car. Note that the race officials will assign a new temporary number for your car just for the races. Inspections: On derby day, your car will be inspected for safety. Any cars that do not pass inspection can be adjusted and resubmitted for inspection. A garage will be available and will have some tools and supplies, but we recommended you bring a few tools of your own, just in case. (We are trying to get a power source for power tools, but it cannot be guaranteed. Wrenches, ratchets, and other hand tools are recommended). Items to consider: o No exposed screw heads or tips. These can be sharp and dangerous. o All wood must be fastened securely. Extra Points: Your team will get extra points for any of the following: (10 points) Newly-made cars. Older cars are welcome as well, but may not be used in the car judging portion. (5 points) Refurbished cars. Cars that pre-existed but were modified (new paint jobs, pinstriping, new features, etc) may receive partial credit. (5 points) Using recycled or reused materials. Applies only to newly-made cars. (5 points) Seatbelts. (2 points) Handbrakes. While not required for the Derby, they are a good safety feature should the pushers lose control. With a detachable handle, the pushmobile becomes a downhill racer for another time (safety rules always apply). Handbrakes used inside buildings like gyms or cafeterias may damage or scuff the flooring, so be cautious. The handbrake may be used in the races. (2 points) Hand grip on the push handle. Suggestions: Make the car light. Heavier cars are harder to start and stop. Plan to use your car in the future. Make the push handle detachable. It makes for easier transport in vehicles and storage. Put the seat closer to the steering axle for more-responsive control of the car. Your car will be around for a long time. Make your car adjustable for growth as your Scout grows.
Be creative! Visit Scout-safe web sites, YouTube and other places to get ideas. Consider using your car in parades, at family gatherings, play time with their friends, and more. The Scouts will want to show off their handy work! Sample Below is a sample cubmobile design advocated by the BSA. To make this a pushmobile, simply add the push handle to the back, and you may remove the handbrake if desired.