When I was a Cub Scout mom, we handled the adding-weight problem by going to the supermarket (yes, the clerks will look at you funny. The post office also has accurate scales, but if you want anonymity to do this weird thing, the supermarket in the next town is best. Believe me, this is a lot easier than going into a bait store and asking for DEAD minnows for your son's science project!) with the almost-finished car and a pile of lead fishing sinkers. We had the car weighed in the produce department and added sinkers to bring it up to a little MORE THAN five ounces. Then we went home, bored out a suitable-size hole underneath the car (centered, in case you need to know), then used melted wax to hold the sinkers in place. On weigh-in day, it was a simple matter to carve out a few of the sinkers with a pocket knife to get it EXACTLY to weight. We came in third!
My husband, who is the leader of Boy Scout Troop 21 in Pataskala, Ohio,
gives these tips: Aerodynamics is not really important because the cars
don't exceed 30 mph. The added weight provides inertia to keep the cars
rolling once they hit the flat section of track. The very most important
thing to get right is the wheels--alignment of the nail "axles" and balance
of the plastic "tires." Be sure to sand off any irregularities on the "tread."
So, there you have it, from a two-time Pinewood Derby mother and Boy Scout-leader father who is an "expert on everything."
Sarah Dalton
