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Make sure your Pinewood Derby car wheels are round. It's as easy as ABC! 

Example of pinewood car


How to Check the Roundness of Your Pinewood Derby Car Wheels

Pinewood Derby Wheel Gauge

Pinewood Derby Wheel Roundness Gauge


To check the roundness of a wheel, slide the wheel on the pin with the spoke side of the wheel facing to the left. The gauge pin should ride on the center area of the wheel tread.

Depending on the diameter of your wheel you may need to zero the gauge. To do this, loosen the indicator set screw with the provided allen wrench and lightly tighten the screw so you can move the indicator up and down with light pressure on the set screw. Adjust the indicator up or down until the indicator hand reads zero. Lightly tighten the indicator set screw.

The indicator reads .001 inches per division. Rotate the wheel one turn and record the high and low reading on the indicator. For example, if the indicator reads –2 divisions and plus one division then the wheel is out of round by .003. The ultimate goal is zero reading movement as you rotate the wheel. The more a wheel is out of round, the more the wheel will bounce as it rolls.

Repeat the above steps by moving the wheel in and out to allow the indicator to check different areas of the wheel tread.


Wide Tip option

The optional Wide Tip replaces the ball tip that is included in the wheel gauge. The Wide tip measures the full width of the wheel thread in one pass so it simulates the track surface and eliminates the need to reposition the wheel to check different parts of the tread.

If you have access to extra wheels, use the gauge to find four wheels with the least amount of deviation.

Wheel Shaver

You can round your wheels by using our
Wheel Shaver tool.
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