Thursday, January 15, 2009

Pinewood Derby 1 of 4

The pinewood derby is a model car race for scouts age 8-10. It's a simple wooden car with plastic wheels held on with nails as axles. They roll down a sloped track accelerated only by the force of gravity. The key is to make the wheel movement on the axles as frictionless as possible by smoothing out all surfaces that the wheels may rub against.
This will be my third pinewood derby as a scout leader. The race is two weeks away and the last two years my son Shule has been in the program so we made cars together. The first year he made the "Mammal Mobile".
He decided to make it brown and green camouflage with yellow eyes in front. The pink sticker is just for identification purposes during the race and wasn't part of the design. It wasn't a bad car but we got to the race as it was starting and didn't have time to apply any graphite. This was a disastrous move and I'm pretty sure his was the slowest car that year. Each time it went down the track you could hear the squeaking of the un-lubricated wheels. His was the only car that sounded like that! I felt so awful but he won the "best paint job" award and went home not totally devastated.

With lesson learned about how important graphite on the wheels is the next year was much better. He made the "Titan" which was to resemble a ship. He placed 4th out of about 18 and it was really very close. This is his car on the right just coming in short of the second place winner in red. You can imagine how close he was to the third place car.

The derby is the biggest and potentially the funnest event of the whole Cub Scout year, it doesn't come without stress though. The biggest issue I have with the race is that building a suitable car is not a job that most 8-10 year olds can practically do. It is almost totally necessary to have help from family and scout leaders which is fine but because of the competitive aspect (trophies are awarded to top 3 places) it just gets a little weird knowing that the boys don't all get equal ammounts of adult help. In order to combat the potential injustice, our troop devotes 3 January meetings to working on the cars together so kids without access to tools and help at home can have a chance for adult leaders to help. Seems like a good idea but what we can do is still limited and we mostly just get the cars shaped and sanded which has a neglidgible effect on how fast the car is. Getting the wheels straight, spinning smoothly and the cars weighted up to 5 ounces is what makes most of the difference and these are the last things you do.

When I was a kid I remember participating in 2 derbys, I vaguely remember a red car and a blue car. I remember working on my back porch with the block of pine and a hand saw. I made a cut that looked fine from my angle but it turns out that it was croocked and the cut on the other end of the block went partway through where the axle was supposed to go. I was very upset and felt that I ruined my car. Tears were shed. Later I did get help to salvage it and we were able to make it so the wheel would stay on and I could race it, but I never had one of the fast cars. It was ok that I never placed, I would have liked to but looking back on it I'm glad I even knew how to use a saw by myself even if I couldn't cut straight. My boys aren't good with a saw, I think most 8 year olds who aren't raised on a farm or in a woodshop or something won't have the muscle to properly use a hand saw and heaven knows we won't let them get their hands on power tools. I don't even know how to use a power saw.

So I let my boys design the car, I cut it with the hand saw and they help with sanding and painting. I have them help a little as I spin the nails in a drill and smooth and polish them. I try to explain about reducing friction and why we do these things but until the race is actually happening, they pretty much only care about making their car look cool.

This will be Shule's 3rd and final race, but I now have Shazer in the program so we are doing 2 cars this year and we have brother against brother which adds a whole new level of competetion. So far we have the cars cut and have started to do some sanding. Shule's toad car is to the right and Shazer's rocket style car to the left (facing away from the camera to show off the fancy rear).I will do 3 more posts about the derby, one next week all about getting the wheels and axles ready for speed, I'll post some photos and share what tips I know. Then I'll do a short post just before the race to show how the cars turned out and another just after the race with the results of course.

1 comment:

the Marvelous Mrs. M said...

Really well written post! Thanks!