Wheel Alignment Rig.

[Dawson]

Hello,
Does anyone of you guys have an idea for making their own wheel aligners with homemade tools without using any form of laser or computer alignment equipment? I have found a lot of information about the measurement of caster and camber from internet, but most of them are using the caster-camber gauge and turntables to measure it. Is it possible to make the gauge by using some simple materials or structures which can provide precise adjustments for our wheel alignment? Furthermore, what is the method for finding the accurate adjustment/alignment setting of camber, caster, toe and steering axis inclination? Will there any formulas for calculating the front-end geometry that I mentioned above?

Thank you very much.
Dawson.

[Patrick W. Crane]

WE use the "two strings and to tubes" method of aligning the wheels. put the tubes across the front and back of the car and make sure they are square to teh car. then tie string front tube to back tube along the sides of the car (make sure these are perp. to the tubes). slide the strings in till they are close enough that you can square the wheels.

A digital level is great for camber.

for toe just measure across the fronts of the front rims and compare to backs of the front rims.

the other ones we use clacs for and i forget them.

[Buckingham]

to measure castor, measure your camber angle at zero steer, some steer left, some steer right, and then use some trig to figure out what castor angle would cause the camber change vs steer angle that you measured. Make sure to measure steer angle at the wheel/tire, not the steering wheel unless you know you have 100.00% parallel steer.

[Akos]

Patrick is pretty much right. Tube and string is the simplest. They are also easy to take to the track with you.

The way I usually make them is first by cutting the string grooves on the tubes so that it is just a bit wider than the widest part of the car (this is usually the front wheel). This way the two strings are guaranteed to be parallel.

Make up some simple brackets that can bolt up to the car. I usually weld two split ring collars to the bracket, this way the tubes can be easaly adjusted. To center up the srings, I usually just measure the spindle on each wheel. Adjust them till the distance is the same left and right. Now your strings should be nice and square.

One thing that really helps is a way to lock the steering rack. A pice of tube cut in half that slips over the rack between the body and the stops works great.

Good Luck

[RacingManiac]

Akos is spot on...and he made ours too...lol

I mean if its good enough for a champcar team I saw last year, no reason it's not good enough for the rest of us...

[Tommo]

I was wondering what level of accuracy you guys get with the tube/string technique

Cheers

[Denny Trimble]

http://students.washington.edu/dennyt/fsae/strings.jpg