I have a Hardinge HC on which the spindle speed control jack screw
motor is not turning.
Not sure if it is an electrical problem or what. Everything else
works on the machine and the spindle spins nice and quiet, but I
can't adjust the speed with the knobs.
The nut is down at the bottom of the jack screw.
Somebody who has an HC says that he's seen those machines do that, and
to kick the motor while in speed 2 and adjust the pot/knob up. I
tried that, starting from light kicks to pretty firm, but no luck.

Looking for suggestions on how to fix it.