Derby car time

[LCHIEN]

My grandson is in his last year as a CubScout, going to Arrow of Light next week to promote to BoyScout.
checkin for this, his last Pinewood Derby is Thursday so time was running out we had to work in the very cold shop to finish drilling the axle holes and weighting up the car and truing the wheel alignment.
the car weighed only 2.2 ounces so I needed to put 2.8 oz of weight. Drilled 1", 3/4" and two 1/2" holes to pour lead. It's was so cold it took forever for my solder pot to liquefy.
You want to get as close to 5.00 oz without going over. The weight of the car with 2 poured-in weight was 4.960 with 3 #2 screws added for fine adjustment (their "official" scale might be off) it came to 4.992 oz.

The yellow "Pancake" one is his. The other is mine from a couple of years ago for speed & rolling resistance comparison on the test track. I didn't do my own for the first time, this will probably be my last participation as he is graduating cub scouts.
he chose the shape and bandsawed the body. And the motif and paint. Apparently there's a popular song called "I'm a Pancake". https://www.youtube.com/watch?v=J3l48QQ7y4A

[leehljp]

I like the way you do what you can to the the weight as close as possible without going over.

After your grandson graduates from cub scouts, Grandpa should work with him in building a gas go-cart. Better yet with your engineering skills, both of you could build a baby Tesla electric go-cart!

[LCHIEN]

One of my favorites from several years ago.
Wasn't fast but no one got in the way, haha.

[leehljp]

But It looks a half an oz overweight for a Derby car. ;-)

[LCHIEN]

I raised the middle wheels to keep rolling losses to a minimum, only 4 outer wheels roll. But it only needed two small weights to make it 5 oz. Still it was slow because of the aerodynamics compared to the wedge shaped cars 1/2 an inch thick. We knew it would be slow but my oldest grandson wanted get a design award