I already have a VFD on my machine, but the alternate way I was thinking of controlling the spindle speed was by putting an index mark on the spindle, and then using a stepper motor in place of the original air motor to increase or decrease the spindle speed using the vari-speed unit. I haven't exactly worked out the electronics, it's just an idea at this point. I would think if there were an index mark on the spindle itself, it would be more accurate than the original potentiometer.
Has anyone taken this approach before? If so, how?
NEATman |