Here is a thing I did some time ago. It is a portable simulator of a revolting camshaft. Time to show it:
First, wheels were cut from a 2mm thick steel sheet with a water-jet according to a CAD drawing. It is a decent method of cutting, quite precise. The cut surface is a bit rugged and you can clearly see that the edge is not exactly the right angle, but anyway this method was way better here than plasma or laser cut. You can see some rusty marks caused by the fluid used during cutting.
I cleaned the wheels and painted them later on:
Assembling the wheels on the motor shaft was quite a challenging part. I decided to cut a thread on the shaft and lock the wheel on the shaft with two nuts. I used a hand thread die cause I had no access to a lathe:
The job was very tough, the material of the shaft is very hard and I did not manage to cut the thread perfectly even. The result was good enough though:
The sensor that senses wheel movement is an induction anti-lock braking system sensor, taken from a Polish car called "Polonez" ;) The assembled device looks like this:
And here is the oscillogram of the working device. You can see peaks are not even. That is because the axis of the thread does not cover the axis of the shaft close enough. That causes deviations of the spinning movement. This should not be the problem since the thing that interests us the most are the points where signal crosses through zero. The gap between peaks is a missing tooth that marks the position of the wheel.
