Here is how it is done as explained by a College Professor of Mathematics:

The Hunter Alignment Machine machine measures from the edge of the rim. Tire size does not affect the readings.

First, you'll need to measure the radius of your wheel. Measure from the center to the edge. For my 17" wheel that was 9.25".

The use this equation: 2(3.14) x radius = X

For me that equaled: 2(3.14)=6.28
6.28 x 9.25=58.09

The next equation will vary depending upon the inches you want to convert.

Inches/X

I wanted to convert 3/16" to degrees so:

3/16"=.1875 .1875/58.09=0.00322775

Then take that number and multiply by 360

0.00322775 x 360= 1.16

Bingo! 1.16 degree equals 3/16"

Here is how it works for 1/16"

2 x 3.14=6.28 6.28 x 9.25=58.09

1/16"=.0625 .0625/58.09=0.001075916

0.001075916 x 360=0.38

-John Pruner
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