Re: [CAD_CAM_EDM_DRO] calibrating cnc systems

Hi Scott,

It's all in the numbers. The stepper is connected to a lead screw or
ball screw which as turns/inch (or mm's). It may be connected through
pulleys, which have a ratio. The stepper is usually 200 steps/rev., 400
if you're half stepping. Multiply stuff out; for example: 20 tpi lead
screw * 400 steps/rev = 8000 steps per inch of travel (no pulleys). SO,
8000 is our "scale". If you want to move 0.5", then 0.5 * 8000 = 4000
steps you will need to generate to make things move the required
distance. In the case of a rotary table, you might have a 72:1 worm
gear, so that with 360 degrees, you get something like 80 steps/degree.

Luckily, the controller program does all this for you!

HTH

Alan KM6VV


"S.L.Ramsay" wrote:

>
> how in the world do you calibrate software so that it knows to turn a stepper motor or servo "X" amount of times to move an exact distance?
>
> Scott