What are some unique propulsion systems for a pinewood derby car project? (2024)

FAQs

What is the most aerodynamic design for a Pinewood Derby car? ›

But aerodynamics rule the day, and the best shape is a simple wedge. Just like a spoiler on the rear of a sports car, the wedge shape allows as much air to flow over the top of the car without hinderance while keeping the car pinned to the track.

A pinewood derby car converts gravitational potential energy to translational kinetic energy (and resulting velocity), rotational kinetic energy in the spinning wheels, and heat from friction.

The following parameters made pinewood derby cars faster: using graphite on the axles and wheels, using lightweight wheels and polished axles, lifting the left front wheel and bending rear axles also raised speed.

No need to get crazy here, but simply having a wedge-shaped Pinewood Derby car instead of the standard block out of the box will equal a 1.4-car advantage at the finish line.

Aerodynamics have little effect in such a short race, but weight does and putting the weight at the back of the car will make your car faster on the flat of the track. Tungsten weights, in most cases, are best because of their high density. Lube the car at the body/wheel friction point.

Can a pinewood derby car be shorter than 7 inches? Yes, you can make your car shorter but it is not recommended. A shorter car will have a lower center of mass at the start so it will have less energy to convert into speed when going down the track.

Throughout the entire motion of the car, the car experiences a number of forces. These forces include gravitational force (weight), normal force, drag force, and frictional force exerted on the wheel as a moment. These forces contribute to changes in the car's energy and thus affect the motion of the car.

The farther the car drops (gravity), the more energy it releases and the faster it will go by the time it reaches the flat portion of the track. If the weight is placed towards the back of the car, it has longer to "drop" (by several inches) than if the weight is placed towards the front of the car.

No wet lubricant is allowed. (Ex: NyOil, NyOil II, WD-40) Only one lubrication is allowed before the beginning of the first race, and then once again before the beginning of the first race of the semi-finals and finals.

Leading and Trailing Edge Fenders: These are the same as the Leading Edge Fenders, with the addition of fenders behind (trailing) the front wheels. These fenders help direct the air over the front of the wheels but also eliminate the turbulence behind the front wheels leading to a faster car.

How do you reduce friction in Pinewood Derby? ›

The easiest way to reduce friction is to lubricate the surfaces that cause friction. Lubrication is an essential part of pinewood derby racing. Purchase a tube of dry PRO Graphite with moly and shoot it onto the axle shaft and inside the wheel bore. Spin the wheel so the graphite works in.

While our ally, gravity, pulls the car down the sloped track, our enemy, friction, is hard at work slowing down the car. In every place where moving parts are in contact (wheels rubbing on the track, the axles, the car body, and the guide rails) friction is at work.

How fast do these things go, anyway? The distribution plot below shows a range of speeds from 177 mph to 229 mph, with most cars exceeding 200 mph.

Try to make the wood as smooth as possible for best results. Do not pre-coat with primer or wood sealer.

The most aerodynamic shape in the world, the teardrop, comes from nature. With its rounded nose at the front that tapers towards the rear, the shape is formed by the flow of water down an object meeting opposition from the air around it.

Are aerodynamics important in a Pinewood Derby car? You bet they are. It is the single most important thing to consider before you cut that block.