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Discussion Starter · #1 ·
I saw this on TMR's webpage. It is their
DIY Toe Alignment Tool

It would work pretty well for setting up your toe in if you only wanted to go by measurements such as 1/8 or 1/4 inch, However, modern vehicles specify degrees of toe. This should be easy to figure out with this alignment tool if we had the Wheel Mounting Surface to Wheel Mounting Surface measurements such as these here:

Factory widths
41-71 cj,fc,commandos---front 51" rear 50 1/2"
72-83 cj narrow track--- " 53 " 50 1/2"
82-86 cj wide track------ " 56" " 54 1/2"
87-01 xj, yj, tj------ " 60" " 60"


If you used TMR's tool, basically angle iron, and measured both front and rear you should be able to calculate the degree of toe-in. I am not that good of a mathematician, but if someone out there would enjoy this exercise, it may be of great service to us all. I contacted TMR, they do not have such a chart, but I bet they would like to get one! We would not really need a chart as much as a formula. For instance my LJ has a wms to wms of 60 inches. I have 1.5 inch Spidertrax spacers on, so the true wms to wms is 63 inches. You would want to put levels on the flat of the angle, and make sure front and rear measurements are taken from the same distance from the axle center . Any Einsteins?
 
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but if someone out there would enjoy this exercise,
Do you have the tool on hand?
They have a 24" dimension for the overall length, but I think per their pic with the tape measures, the measurements should be made at the inner edges of the notches. (see attached image)
Toe in.PNG

Can you supply that dimension?
Thanks.
 

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Old fashioned way imo is best short of a alinement machine. Plus you don't need to spend $ or remove the wheels, just measure off the sharp edges of the tires.
 
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Discussion Starter · #4 ·
Do you have the tool on hand?
They have a 24" dimension for the overall length, but I think per their pic with the tape measures, the measurements should be made at the inner edges of the notches. (see attached image)
View attachment 75756

Can you supply that dimension?
Thanks.
Yes, in my case it would be 62.875 in front of the axle, and 63.125 behind, giving about .25 inch toe-in. If those measurements are 12 inches from the axle centerline, there should be a way to calculate the degree of toe.
 
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Yes, in my case it would be 62.875 in front of the axle, and 63.125 behind, giving about .25 inch toe-in. If those measurements are 12 inches from the axle centerline, there should be a way to calculate the degree of toe.
Yes, there is.
The WMS to WMS doesn't really matter as you are only looking at the difference between the front and rear measurements.(as you stated in your example)

The measurement that is important is the distance from the centerline of the hub to the point of measurement on the tool.
It looked like the instructions were showing getting the measurements in the notches that I highlighted on the attachment. Which would be less than 12" from centerline.
As long as the points of measurement on the tool are the same distance from the centerline, the difference between those measurements (in your example 62.875 and 63.125) would be the number to use in the calculations
sine = opposite (1/2 of the difference between the measurements) divided by hypotenuse (distance between the points of measurement on tool)

The point is the distance between the measuring points on the tool is what is needed for the calculation.
If you read this far, you can go to this link for a simple calculator to convert measurements to degrees:

Convert Toe Inches to Degrees
 

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Discussion Starter · #6 ·
^^^^^ Now that is very helpful, Thank you!
 
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^^^^^ Now that is very helpful, Thank you!
I'm sure you mean the link. :LOL:

I found it looking for a good chart/calculator to convert the calculated sine to degrees.
I generally use trig to calculate the required degrees of bend for offsets and kicks in conduits. Those charts range from one to ninety degrees, hence my searching.
 

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What about a 10 dolllar speed square from Home Depot? Mark the floor where the square is at the front and rear centerline of the front tires where the moulding is, then draw your trapezoid and measure the angles?
 
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