Things You'll Need
Pinewood Derby car kit
Hand-held metal file
Dremel rotary tool with polishing and grinding bits (optional)
Steel polish available at hardware stores
Pinewood Derby racers are miniature cars of wood, metal and plastic used in competitive racing, typically with the Cub Scouts and Boy Scouts of America. Rules governing the construction techniques and materials used in Pinewood Derby cars outline how the wheels may be attached to the axles. Polishing the axles helps remove defects in the original construction of the parts, making the car roll faster on the track.
Examine both axles for burrs or other protrusions from the manufacturing process.
File the axles smooth with a hand file or use a stone bit in an electric Dremel tool.
Smooth each axle further with fine-grit sandpaper or a Dremel tool grit wheel.
Add a daub of steel polish to a cotton swab and polish the length of each axle.
Dip the tip of a pipe cleaner in steel polish and push it through the center hole of each plastic wheel that comes with the Pinewood Derby car kit.
Insert the axle through the wheel and check for movement and friction before installing on the car.
Although optional, a Dremel rotary tool makes polishing go faster. Using a Dremel also helps ensure a uniform polish around the axle that may be difficult to achieve with a hand-held file.