Getting Started

1. Trace around the block of wood on paper (side view and top view), then sketch the shape you want within those outlines. Cut out these shapes with scissors and use them as templates to mark how the wood should be cut.

2. Shape has little to do with speed. Aerodynamics don't matter much with a small block of wood traveling only 30 feet. Be as creative as you like. Some people have made cars that looked like hot dogs, bananas, ice cream bars, giant pencils, Swiss cheese wedges, watermelon slices, tow trucks, police cars, Batmobiles, alligators, giant candy bars, space ships, sharks, carrots, shoes, canoes, turtles, skateboards, refrigerators, bathtubs, chariots, a celery stalk with peanut butter, a Volkswagon Minibus, screwdrivers, a beaver driving a log, locomotives, penguins on an ice flow, battleships, Radio Flyer wagons, jet fighters, a steak sauce bottle, go carts, surfboards, army tanks, fire engines, and so on.

3. Do not make the front of the car pointed; that makes it hard to set up against the starting dowels.

4. Use a band saw, jig saw or coping saw to rough out the shape, then trim it down using a file or wood rasp. Since files and saws (especially power saws!) can easily cut fingers as well as wood, be sure to have an adult do this part with you. If you don't have access to a saw, ask your Den Leader for help.

5. Weigh all the parts (the wood + the wheels and axles) to see how much weight should be added. The more your car weighs, up to the 5 ounce limit, the faster it will go.

6. Most Cubs use lead to add weight. Some use fishing sinkers, some use shot and some use lead weights specially made for derby racers purchased the Knox Trail Council & Scout Shop (490 Union Avenue, Framingham) or at crafts stores such as Paperama. For the best final appearance, you can drill holes to hide the weights, then cover them over with wood putty, marine epoxy or hot glue. If you decide to add your weight to the underside, remember to check the ground clearance.

7. Every year there's a debate over where to put the weight. Actually, it's simple physics: the cars start out on an incline with the rear end higher than the front but end up at the finish line on a level surface. If you put the weight up high at the rear, the potential energy (force times distance) is greatest and your car will go fastest.

8. After you've added your weights, weigh everything again! You may be surprised at how much the glue or epoxy you used to mount the weights has added.

9. Sand your car body very smooth before trying to paint it. Try to get every saw mark or file mark out. Start with coarse paper and keep working until you're down to about 200 grit or better.