How to Build a Pinewood Derby Car
Pinewood derby cars were created in 1952. Cub master, dad and model-maker Don Murphy came up with idea to have a father-son activity for his 10-year-old. He wanted something similar to the Soapbox Derby, which required the child to be older. Murphy and several Scout committee members came up with the pinewood derby kit and he came up with the concept and rules for the boys to design, build and race cars. Building a pinewood derby car is a challenging project for the parent and child. It is mostly used for Cub Scout races but the concept can be adapted by any group.
Things You'll Need
- Basic pinewood derby kit, which includes a wood block, axles, wheels and numeric decals
- Tracing paper
- Safety glasses
- Coping saw, Dremel saw or scroll saw
- Drill and bits
- Wood putty
- Tubular weights
- 400- or 600-grit sandpaper
- Small file
- Cloth
- 80-grit and 220-grit garnet sandpaper
- Metal polish
- Sanding sealer
- Paint
- Lubricant
- Decals
Instructions
-
-
1
Design your car on paper before cutting your block of wood. If you are not sure what you want it to look like, get ideas from websites like www.pinewoodpro.com or play with basic designs at www.scouting.org. The fastest designs are wedge-shaped. The best design may not be the fastest car.
-
2
Use transfer paper to transfer the design onto the block of wood. The wood from the kit is almost 7 inches long. Measure the dimensions of the design before cutting the block to stay within specifications. Cut out the block and using a saw and wearing safety glasses.
-
-
3
Prepare the wheel mount. Consider moving the two axle slots to the ends of the wood. This will give it a longer wheelbase, which will increase speed. The car length cannot exceed 7 inches, so make sure that the wheel slots are back no less than half the diameter of the wheel. Cut the axle slots exactly square to the sides, so that the axles have good alignment on the track. Use a 2.3 mm drill bit. and drill press to make the holes. Insert axles to ensure a perfect fit after the paint has dried.
-
4
Drill the hole behind the first axle, place in the weight and fill it in with wood putty. Weigh the car on accurate scales. A pinewood derby car for the Cub Scouts cannot weigh more than 5 oz. Weights need to be placed in the front of the car to gain the most speed. Low, skinny designs that weigh the maximum allowed have a better chance of winning.
-
5
Use sand paper or a belt sander to smooth out the car. Remove any saw blade marks. Be sure to wear safety glasses. If you are not using a power sander, a 100 -or 120-grit paper and wood or rubber block will smooth the filler and rough spots. Use 220-grit paper to remove sanding marks and finish smoothing out the car by using 400- or 800-grit paper.
-
6
Apply a wood sanding sealer to the pinewood derby car. It provides a base coat and acts as a primer. Paint the main color on the car and let it dry. Then paint any designs with the other colors, using a fine-tip paint brush. Let the paint dry and apply the decals as desired.
-
7
Wax the surface of the car and lubricate the axles and axle holes with graphite. Secure the wheels and axles into place. Weigh and measure the finished pinewood derby car to make sure it is within the rules of the race.
-
1
Tips & Warnings
Know the rules for your region and abide by them.
If your region allows it, lightly sanding the wheels will help with speed.
Graphite is lead-based and is toxic.
The weights may also be lead.
Wash hands thoroughly after handling lead.
Do not use any form of mercury for weights.
References
Resources
- Photo Credit morguefile.com
