Professional League Racers build the fastest Pinewood Derby® cars in the world. This article will give a broad overview of the features of a typical league car.
Over the years, as Pinewood Derby® racers pushed their weights back further to gain more potential energy, the cars became unstable and wiggled. This banging back and forth along the center rail slows the car down considerably. Racers discovered that if the car gently rubbed or steered into the center rail of the track, it would be more stable and, therefore, faster. This steering of the Pinewood Derby® car is known as rail riding.
The slight friction generated by the front wheel rubbing the center rail slows the car MUCH LESS than a straight running, traditional car becoming unstable.
Steer is induced by turning the right front wheel inward (see left image). This is known as toe-in. Tilting the wheel (see right image) stabilizes it and reduces friction. This titling is referred to as camber. The non-steering front wheel is raised or lifted slightly off the track, significantly reducing rolling inertia.
There are two options for turning and tilting the front wheel, causing
the car to steer into the rail.
OPTION 1: Drill the front axle hole at a compound angle that will impart camber (tilt) and toe (turn) into the front wheel, inducing the steer. Drilling the front axle hole at the proper angle can be difficult and limits the ability to adjust the amount the car steers; however, a tool discussed later in this book easily allows the drilling of steer into the car.
Front right axle hole drilled at compound angle that turns (toe) and tilts (camber) the front axle/wheel.
Some race rules prohibit the bending of axles. If running a rail rider setup, drilling the hole at the compound angle to induce steer is the only option.
OPTION 2: Pro racers prefer this option. Bending one of the front axles (usually the right front) induces the steer. The wheel tilts and turns inward toward the car body by twisting the axle. This amount needs fine-tuning; therefore, a groove is typically cut into the head of the axle so the racer can turn the axle using a flat-head screwdriver. Racers will roll their car down a slightly inclined surface to see how much it turns over a given distance (typically four feet). Setting the steer is discussed in more detail in the Assembly article.
Anatomy of a Professional Pinewood Derby® Rail Riding Car
Below are key features of professional league racing Pinewood Derby® cars. These features are discussed in more detail in other articles.
Articles in this series (click to read):