I have no idea who Peigi Woodruff is, but he/she/it continues to flood my mail box with these ads for cheap drugs. Too bad she’s not offering free shipping on standard delivery orders. Also, she does not take credit cards. Why should I buy anything that I can’t buy with my travel miles card?
–
TC
_____________________________
Thanks for all the comments and advice on how to build a Pinewood Derby car. It’s amazing how many guys at the office are experts at building these things. Really, everyone seems to have the solution. There are a couple of places on the net making a rather tidy profit selling “never lose” plans too. But we wanted to not go that route so that THE BOY would be involved at every step of the process.
And yes AlaskaMike you did warn me about the ground clearance. I measured the car several times at home with the kit the Scout store sells and it always passed. It also passed at the workshop when we measured it. It was when we put it on the actual track that it got stuck.
A couple of you have commented that the car is not aerodynamically sound. That’s true. But at the size of the car (7 inches long) that is not as much of a factor as it would be on something bigger. In looking at past winners I noticed that the design had very little to do with the place the car runs. One thing that does play into the equation is friction. I’ve shaved and cleaned the tires as much as the rules will allow. The car uses regular nails as axles for the wheels. So to eliminate friction there I’ve sanded the shaft of the nails smooth. I used a file for the big work and then cloth coated in pumice for to remove all of the fine scratches.
Tonight we’ll set the wheels to the right gap and alignment. Once that is done I can epoxy them into place and we’ll be set.
There was a good bit of discussion last night about the second car. I still think we have time to get it ready, but I’ll be up late tonight to do it.
–
TC
_____________________________
Well, we had to make changes to the car.
One of the other dads in the Pack had a mini-workshop at his house for the guys to test out cars and put on the finishing touches. Long story short, the Flash car didn’t cut the mustard. The weights that THE BOY and I mounted under the car were a fraction too low at some points on the track. It produced a drag that kept the car from making it all the way down the track. A total disaster in the world of Pinewood Derby racing.
Thankfully the dad that was holding the workshop had a shed full of woodworking tools. He loaned me his rotary tool and router bit to hollow out the bottom of the car and recess the weights. This let the car move down the track but it screwed up the weight and balance of the car.
Each car is allowed to weigh no more than 5 ounces. Our car was 4.903 ounces. After I cut out the bottom of the car the weight fell to 4.1 ounces. Far to light to develop any real speed in the downhill portion of the track. I compensated by adding more weights to the car bringing it back to 4.9 ounces. The pictures are after the jump.
Of course drilling out the bottom required me to remove the wheels and axles. Now I’ve got the task of re-setting them and adding more graphite to the shafts.
We also started a second car, but it may not be finished by Friday night.
I had more to comment here...
