Adding weight to a Pinewood Derby car quickly and cheaply.

Picture of Adding weight to a Pinewood Derby car quickly and cheaply.
I was looking for a quick, easy way to add weight to a Pinewood Derby car. You can use lead or tungsten, but they are relatively expensive ($1 - 2 per ounce), come in odd shapes, and you have to figure out a way to attach them to the car. Pennies, which are 97% zinc cost about $0.10 per ounce (or free if you find them under the sofa). An ounce of penny is the same weight as an ounce of lead, so why not go cheap. What you loose in increased volume needed for the same mass, you make up for with the utility of a uniform size and weight object. 

Disclaimer: This is my daughter's car, so no comments about pink or the hearts, please!
Also, no pennies were harmed in the process of this Instructable!
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Step 1: Supplies

Picture of Supplies
Things you need:
 - accurate scale.
 - 3/4" drill bit and drill.
 - some loose pennies.
 - masking tape (optional).
 - hot glue or epoxy (optional).

Step 2: Weight the car

Picture of Weight the car
Pennies are exactly 3/4" in diameter and weight about 0.1 ounce each.

Weigh your car and then add pennies to the scale till you reach the desired weight.

I've been told there are two rules to the Derby:
 - If your car is overweight, you are disqualified.
 - If your car is underweight, you loose.

For our derby, 5 ounces was the limit, and her car started out at 4.5 oz, so we only needed to add five pennies to get close.

Yes, the car does say "I love you Dad and Mom" on the bottom. That makes it go faster.

Thank you so much for this!! This was our first year in scouts and we waited until the last possible moment to add weight. It was such a great idea! So simple! So easy! Thanks for bailing us out!!

yes, superglue and small change is way cheaper than purchased weight.

Pfarmkid3 years ago
we always used quarters
gomiboy3 years ago
Other coins that equal an ounce:

5 quarters
5 nickels + 1 dime
12 dimes

For weighing our cars, we take them to the Post Office and use the self-serve stamp machine, since we don't own our own postal scale.

It's always good to have some pocket change on hand on race day (along with crazy glue or tape) for that last-minute adjustment in case the race scale doesn't agree with yours.

Great idea to post here, and happy racing!
lemonie3 years ago
"I love you Dad and Mom" on the bottom. That makes it go faster.
I like that, and coinage is good for weights.