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We try to answer all questions sent to us. Here are just a few of the questions we have received along with our response.

Where can I find ....?

Where can I find pictures of Pinewood Derby cars?
Here are two sites that I know of with lots of car pictures. They are:

GrandPrix Race Central    Maximum Velocity!


I want to buy a derby track. Where do I look?
Sites that sell tracks include:

Best Track     Microwizard


Where can I find rules for a pinewood derby?
Each organization can have slightly different rules. So I suggest you contact the race leader for your organization. They should supply you with the official rules for your local race. If the rules are not clear, then ask for clarification. If you looking for the official Cub Scout Pinewood Derby Rules, they are posted on:Maximum Velocity Rules Q&A

Where on the internet can I purchase weight for pinewood derby cars?
You can buy lead, steel, zinc, and tungsten weight at Maximum Velocity! You can buy PineCar brand weight at PineCar. Lead weight is about 1.8 times heavier than PineCar weight, while tungsten is about 3.0 times heavier than PineCar weight, and is completely non-toxic.

Our race is this weekend and we are desperate! Where can we buy a pre-made car?
I don't know of any site that sells pre-made cars. Not only would they be very expensive, but buying a pre-made car would go against the spirit of the pinewood derby.

However, you can buy pre-shaped car kits with pockets or holes for weight at: Maximum Velocity! Also, Pinecar sells several models of pre-shaped cars, but you have to create a pocket to hold the weight.


Where can I buy scouting derby kits and replacement wheels/axles?
You can buy scouting kits, and replacement wheels/axles from Maximum Velocity!

What do you think about ....?

Why do heavier cars go faster?
Most derby tracks are of one of the following types.

Track 1 - The track is sloped from the starting line to the finish line.

Track 2 - The track has a slope at the start and then has a long flat area.

Let's pretend you build two cars - car A, and car B. The cars are identical and very well built, except that car A weighs 4 ounces, while car B weighs 5 ounces.

On Track 1, both cars are constantly being pulled down by gravity, and the gravity will pull on both car A and car B equally. Gravity doesn't care about the weight, because in fact gravity is what gives them weight! So, since the cars are identical except for weight, both cars will work equally well, and should finish in a tie (or close since it is impossible to make perfectly identical cars).

Track 2 is different. On this track, both cars are pulled down by gravity while they are on the slope. While they roll down the slope, they continually accelerate. When they reach the flat area, they are going as fast as they can. Then they both start slowing down due to friction. Of course, as the owner of the cars, you want them to slow down very slowly so that they keep going as fast as possible for as long as possible. This is where the weight of the cars is important.

When a car reaches the flat area of the track, it has what is called 'momentum'. Momentum is the measure of how much the car wants to keep rolling along. The momentum is measured by multiplying the speed of the car times the weight of the car. With our two pretend cars A and B, both of them will start the flat area with the same speed, since gravity pulled both of them down equally. However, since car A weighs less than car B, car A will have less momentum. So car A will slow down faster than car B. Since car A slows down faster, car B will win.


What is the best location for the axles?
Many races do not allow the axle location to be moved. However, if you are allowed to the move the axles, the best wheel base (distance between the axles of the car) is when the axles are the furthest apart. So that the wheels do not extend beyond the ends of the car, the axles can be placed 11/16 inch in from either end of the car. This "extended" wheel base thus measures 5-5/8 inch. Note that the "standard" scouting wheel base is about 4-3/8 inch.

There are two reasons why the extended wheel base is the fastest:

  • Wheel alignment - The extended wheel base is easier to align. If a wheel is not perfectly aligned, the effect of that misalignment will be less on the extended wheel base than on the standard wheel base. This is why small automobiles turn much quicker than big automobiles. Since we do not want pinewood derby cars to turn, the longer wheel base is better.

  • Weight position - For pinewood derby tracks that have a slope followed by a long flat section, the best position of the weight is towards the back. This is because the speed of the car at the beginning of the flat part of the track is based (among other factors) on the distance that the center of gravity of the car traveled. Given two identical cars, except that the center of gravity of one car is further towards the rear, that car will have traveled a greater distance, thus, it will have achieved a higher speed. Why is this? While a car is rolling down the slope, it is accelerating. Assuming that the car is well aligned and lubed, it will accelerate until it reaches the flat part of the track. The car that has the longest acceleration time will attain the greatest speed.
Unfortunately, with the standard wheel base, the weight cannot be put too far back, otherwise the car will tend to "pop a wheelie". But with the extended wheel base, the weight can be put right at the back, and the car will still stay on the ground. Thus, the center of gravity of a car with an extended wheel base can be further back on the car, thus it will attain a higher speed.


Do you recommend angling the tires, or making the tires sit flat on the ground?
Some people recommend angling the tires to reduce wheel-to-track friction. But I strongly recommend sitting the wheels flat and straight. The problem with angling is that it greatly increases the friction between the axle and the wheel hub. Each degree of tilt increases the friction by a factor of 1/10 (thus, a 10 degree tilt doubles the friction). Also, if you angle the axles downwards, the wheel hubs will constantly rub on the side of the body. If you angle them upwards, the wheel hubs will constantly rub on the axle hub. So, all things considered, the slight advantage that might be gained in reducing wheel to track friction is overwhelmed by the other increases in friction.

What is the best graphite for pinewood derby cars?
We have tested many brands and recommend Max-V-Lube (sold by Maximum Velocity!)

What type of paint do you suggest using on derby cars?
If you plan to use spraypaint, I suggest Duplicolor primer and paint. Duplicolor paints go on smoothly and dry quickly. I would avoid any types of enamel, as they take a long time to dry and can be hard to apply. If you plan to use brush paint (easier for young kids), then I suggest acrylic primer and paints (sold at hobby shops), which can be cleaned up with water.

How do I make a pinewood derby car go fast?
I can give you some general ideas. If you want more detailed information, I suggest you purchase a booklet from one of the web suppliers. See our Buyers Guide for more information.
  • Make sure the car weighs the full amount (normally 5 ounces)
  • Make sure the car is of full length (normally 7 inches)
  • Put the added weight towards the back of the car. The front-back balance point should be about 1 inch in front of the rear axle.
  • Polish the axles, making sure to remove the spurs by the head of the nail-axle.
  • Make sure the wheels are smooth and free of defects
  • Use a good quality graphite, such as Max-V-Lube
  • Make sure the car rolls as straight as possible, or consider using the rail-riding alignment technique.

2011 by Randy Davis
Updated March 31, 2011