My new Alignment tool

All home made.
Screws, nuts, string, two pendulum needles (from windshield wipers), printed scales and some square, U and L shaped bars.
The front and rear transverse bars have notches at exactly the same distances, this makes a perfect square.
The exhaust tip is quite handy for supporting the rear and the grill for the front.
Once left and right sides are equidistant you have two lines exactly parallel to the center drive line of the car.
The initial calibration was quite time consuming, but once set-up it’s very simple to use.
Ride height tools were used ofcourse.

0.1mm tolerances
Accurate to 0.5mm and 0.25°

The car now drives straight !



Nicely done!!!

Bravo! I can tell that represents a significant amount of thought and ingenuity. Glad to hear that the end results justified the effort.

With both lines equidistant they are parallel to each other…so how do you set the lines to the centreline of the car?

Presume that a wheel is bent. How would you correct for that?

Um… determine that, pre-alignment, fix it, then align it?

Just spit ballin’ here…:wink:

Back in the days of steel wheels, virtually none of them were perfectly straight. Yet many alignment shops used devices that attached to the wheels as these do.

Perhaps true, but that isn’t the point: you illuminate an important other parameter, that one needs to ascertain one’s wheels are true, before an alignment.

If A1=A2 and B1=B2 then A3=A4 and B3=B4

Of course, we must assume that the car is straight to begin with.
All modern alignment machines make this assumption as they all base their measurements only from the wheels.

My wheels are dead straight, checked and verified.
If they are not it sure does complicate things !!

1 Like

Ah haaah…so the set up jig is centred on the wheel hub and the wire is referenced off the hub centreline. That’ll do it!!

Note that your algebra needs another condition added to ensure the system will work.
It’s in the words but not the algebra…heh heh…