Well, first of all, if you are wondering, “What is the pinewood derby?“, it is a major Cub Scout annual event where the boys get to build pinewood derby cars for a race day competition. It is a really fun way for parents and kids to get to bond together as they work on creating the fastest pinewood derby car. My son was in Cub Scouts for five years and we loved all the planned fun activities for boys. You can get super creative with your pinewood derby car (my son’s friend made a cheesecake slice pinewood derby car) but most people try to make fast pinewood derby cars so they can win the race. Today, I will be sharing 7 Pinewood Derby speed tips from Troy Thorne, author of Building the Fastest Pinewood Derby Car (affiliate link below). I hope you and your child enjoy working together on this STEM-related project!
Troy Thorne is a woodworker, artist and derby-winning dad! In his book, he shares his expert tips, techniques and amazing patterns so parents and scouts of any skill can build a jaw-dropping, prize-winning car that’s fast out of the gate.
Make Fast Pinewood Derby Cars With These 7 Pinewood Derby Speed Tips From Troy Thorne
You don’t start creating a Pinewood Derby car by jumping right in and starting to cut away wood. You must first understand the principles of speed before you can apply them. I’ve been asked many times what the secret is to building a fast car. I always reply the same way—there is no magic “one” thing you can do to make your car faster. It is a combination of a lot of different things that all add up to a very fast car pinewood derby car. Here are a Pinewood Derby speed tips to pay attention to if you want your car to cross the finish line first!
More friction equals less speed. You might have built a car that has lots of potential energy, but not all of that energy converts into speed. Some energy changes into heat when surfaces, like the wheel and the axle, or the wheel and the track, rub against each other. This is friction. If you can cut down on this waste of the Pinewood Derby car’s potential energy, you will increase your speed.
If you maximize all the potential energy, polish the wheels and axles to reduce all the friction, and then just stick the wheels on your car, you will be very surprised how poorly your car will perform. If your Pinewood Derby car travels down the track and bounces off the guide rail a few times, it will be losing speed every time it touches the rail. Or, your alignment may be so far off that your car will get the “death wobble,” where the back of the car wobbles back and forth. A finely aligned car will look like it’s accelerating down the flat part of the track. What’s really happening is an aligned car isn’t losing as much speed as the unaligned cars.
Of all the Pinewood Derby speed tips, properly adding weights to your car is one of the easiest things you can do to make your car speedy. There are many types of metal you can use to add weight to your car. I have seen all types of things used, including coins, washers, and even nuts and bolts. I get asked all the time about what is the best type of weight to use. A lot depends on the type of car you’re building. Very thin cars are easier to build with tungsten weights. Tungsten is very dense, so you can fit a lot more weight in a small space than you can with lead. Tungsten is available in many useful shapes, making weighting your car even easier.
Remove the burrs! All official BSA axles, when they first come out of the box, have a set of small burrs located underneath the head of the axle. Whenever the wheel and the axle head touch, these little burrs create a large amount of friction. The burrs are almost like mini brakes, so they must be removed. The underside of the axle head must be polished smooth as well. Remember that friction is the enemy of speed, and these little burrs are a major source of friction for Pinewood Derby cars.
Taper the Axle Head
As the axle head and the wheel rub against each other, they create friction, which slows your car down. Another important one of these Pinewood Derby speed tips, is that you can minimize this friction by tapering the head of the axle with an electric drill and a small triangular file. This makes the area of the axle head that touches the wheel much smaller.
Polish the Axles
A great deal of friction is created when the wheel rubs against the axle while it is turning. To reduce this friction, make the surface of the axle as smooth as it can be. Believe it or not, the outcome of a race may well depend upon who does the best job polishing their Pinewood Derby car axles.
Use a Calliper
With a calliper you can measure parts of your pinewood car down to the thousands of an inch. It’s very useful to measure the diameter of your axles to help you select the roundest axles. You can use it throughout the polishing process to make sure you’re not removing too much material from the axles. It can also be used the check the outside diameter of the wheels to identify any wheels that are out of round.
For more Pinewood Derby speed tips and secrets check out Building the Fastest Pinewood Derby Car: Speed Secrets for Crossing the Finish Line First! If you are serious out building the fastest Pinewood Derby cars, you will definitely want access to all his tried and true tips and Pinewood Derby car designs.
Have you and your son ever participated in the Pinewood Derby? Do you have any tips you would add to this list for how to build fast Pinewood Derby cars?