Wheel clearance, or gap spacing, is the easiest thing to fix and perhaps the adjustment that most people get wrong. If wheels are too far out from the car body, the car wobbles from sliding left or right on the axles. If the wheels are too
close, they rub against the car body slowing your car down like ABS brakes.
What is the optimal spacing between the wheel and the car body?
Your PRO Alignment Tool makes wheel spacing a snap.
The Tool thickness is exactly the spacing you need. Just insert the Tool Wheel Clearance slot between the wheel and car body, then push the wheel in as far as it will go against the tool.
Remove the tool and you have perfect wheel spacing! Repeat for each wheel.
If your axles are not perfectly straight, your car will steer left or right, causing it to hit the center rail as it goes down the track. This causes friction and drag on your car, which sloooows your car down.
With all four axles inserted into the car block, place the tool flat on the bottom of the car. Be sure the ruler is flush with the edges of the block so everything is square.
You can see if the axles are square by looking at the parallel lines on the tool in comparison to the axles. Your axles should be exactly parallel to the lines on the ruler. If not, you need to re-insert the axles so they are parallel.
Better yet, drill the axle slot using our PRO Body Tool, which makes a perfectly straight axle hole. Alternately, our Precision Drilled Block has perfectly aligned axle holes because they were drilled with a drill press.
What is Camber and why do you care?
Camber is the inward or outward tilt of the top of the wheel from true vertical. If the top of the wheel is tilted inward, it has a Negative Camber. If the top of the wheel is Tilted Outward, it has a Positive Camber. If the wheel is straight
up and down on a true vertical line, the Camber is measured at Zero (0°).
If Camber is not zero, your wheels are not resting flat on the track and therefore could ride inward or outward on the axle. Zero camber will allow your wheels to stay centered on the axle, keeping it from creating drag by hitting the nail head
or car body.
To measure camber, with your car on a flat surface, place the PRO Alignment Tool against a wheel and check that the wheel is perfectly flat against the tool. If not, you have camber and you need to adjust your axles until camber is zero.
Once again, a perfectly straight axle slot, drilled with the PRO Body Tool will eliminate camber. Alternately, our Precision Drilled Block eliminates camber.
Toe In, Toe Out
What is Toe and why do you care?
Toe relates to the difference in the distance between the front of the tires and the rear of the tires on the same axle, or to the vehicle centerline. Toe-in, or positive toe, is defined as the front of the tires being closer together than
the rear of the tires. Toe-out, or negative toe, is when the rear of the tires are closer together than the front of the tires. Zero toe is when the tires are parallel to each other.
If your wheels toe inward, your wheels will literally
slide on the track slightly as the wheels turn, causing friction. You want to eliminate Toe in and toe out, so your wheels are perfectly straight.
Place the tool flat on the bottom of the car and pull the wheels out to the axle head. Compare where each wheel lines up with the lines on the PRO Alignment Tool. They should all match.
With the car on a flat surface, put the PRO Alignment Tool on its edge and look under the car to be sure nothing is protruding below the 3/8” Track Clearance line.
Length and Width Dimensions
Your car should measure 7” long by 2 ¾” wide. Use the ruler on the PRO Alignment Guide to measure length and width to be sure it is within these dimensions.
While some specialty trim items may exceed these dimensions, be sure the width especially does not exceed too much (1/2” or more) as this could cause your car to hit the cars in adjacent tracks, causing collisions, which is not good for you
or the car you hit!
The PRO Alignment Tool is made of a flexible, durable white polycarbonate... it won't break or wear.
Another tool to help you make a high performance pinewood derby car...from the derby car experts at Pinewood Pro.