Cub Scouts surprised Caleb and me with a challenge we found nearly insurmountable: build a Pinewood Derby car. They provided us a box I decided not to open until a week before the race, and I discovered its contents included only a block of wood, nails, plastic wheels and a short set of guidelines. Are you kidding me?!?! I thought this would be a ten minute endeavor. Not so.
I’m not considered a handy-man by anyone. My garage tool acumen is only slightly worse than my putting a ponytail in Lucy’s hair acumen. In fact, I had destroyed my stapler only moments before beginning my research on how to make Caleb’s derby car–this was three days before the race–because it was empty of staples and I didn’t find the cartridge eject button before my temper erupted.
Nevertheless, Caleb and I prevailed. And we didn’t spend hundreds of hours on the car, either.
This is the simplest set of directions I can give for any Dad who needs to fabricate their first Pinewood Derby car, and make it competitive.
1) Design your car-From my research, I’ve gathered that the aerodynamics of the car contribute little to its performance. Since Caleb’s only request was a ‘Car’ inspired design, we traced Chick Hicks on the block of wood. A band saw finished our cuts in a matter of minutes; if you only have a hand saw, don’t fret; simple cuts don’t take long. ***See step four to make sure your design allows for the addition of weight to the back of the car, however.
2) Sand your design- Lower to higher grit until you get the smooth feel you desire. Caleb loved sanding his car’s body; he really worked hard at it. This is more of an aesthetic step.
3) Make cuts for axel placement (don’t use the precut ones)–Use a saw to get wheels as far apart lengthwise as the rule restrictions allow. DO THIS CAREFULLY. Next to adding maximum weight to the car in the right proportions, this is the next most important step. Be certain your cuts are at ninety degrees to the car’s body so the axels will run perpendicular to the body. If you don’t, the wobble will slow the car.
4) Add weight--If you are as lazy and cheap as I am, don’t go to the Boy Scout store and buy weights. Just make a design that allows you do drill out the trunk area. Then, put the car on a scale with the wheels and axels (I went to the grocery store and put it on their deli scale.) Then dump the weights in until you are 0.3 ounces from the max weight (max weight is five ounces), or if they don’t have ounces on the scale, max weight is 0.31 lbs (so fill to 0.29 lbs). The reason for not going to max weight at this point is due to the addition of Play-Doh over the weights at the end. Ideal weight distribution is eighty percent posterior and twenty percent anterior of the car.
5) Paint the Car–You can skip this step entirely if you want. I spent more time than I wanted painting our car because Caleb only cared that it looked like Chick Hicks. Still, he and I only painted a couple hours total (we added stickers also).
6) Buy powdered graphite–This lubrication is essential for your car to be competitive. It will reduce the resistance of the wheel on the axel substantially, allowing it to go much faster. Apply it to the axel and spin wheel on it to lubricate well.
7) Place axels and wheels onto car–Again, tap those axels in perpendicular, giving them a three to five degree tilt so they run on the inside of the wheel slightly. If you can, take one anterior wheel out of contact with the ground completely; it will go faster with reduced resistance.
8) Test run-run car on the floor to make certain it is running straight. Any deviation will slow the car down because it will bump into the guide the car runs on. Adjust axels accordingly until it is perfect. This was our biggest mistake. I believe, had I spent the most time working on this step, our car would have qualified for the district race.
9) Go to race site--Put car onto scale and add weight until you are at exactly five ounces, sealing the weight into the back with Play-Doh. This way you can add weight without worrying about being over the limit when you get to the race.
Optionals: 1)Some people bake their wood block in the oven before car fabrication. This removes water and allows you to add more weight later. 2) Sand axels slightly to remove any imperfections (do this carefully or you may warp or weaken your axel) 3)Sometimes the track is set up the night before; if you want to trial run, go for it. As for us, we had just started the paint at this point.
Total hours we spent on the car (excluding painting and driving to get graphite and weigh car): 2 hours. In fact, typing this blog post and loading the pictures rivals the time we spent manufacturing our Chick Hicks.
Our results? We were only like three cars from qualifying for the district race. I think with more time spent on wheel alignment, we could have easily broke the top 10% of the cars.
Even if you have no desire to participate in this race, do it anyway. Caleb and I bonded so well over the project that I feel sick about the fact I considered withdrawing from the competition.
Just have fun with the project, even if you have expectations as low as I did. The Pinewood Derby isn’t about winning; it’s about having fun.
At least, that’s what the losers tell me. Follow these directions, and you’ll have more than fun; you’ll have bragging rights.
If any of you handy men have anything to add, I’d love to hear it. Next year we plan on winning, and your help may make the difference.