I have a craftsman lathe ( model 351.217170). It uses a potentiometer with integral SPST switch for speed control. Today, I turned the pot off to inspect my sanding and then it would not turn back on. The safety feature on this lathe requires that the potentiometer be off before the main switch is applied. If it is not off, the lathe won't start. Once you have it running, you can leave the main power switch on and rotate the potentiometer to off to stop the lathe. Then rotate back on to start back up. The whole time the main power switch must be on.

My symptoms are no motor noise at all. Fan runs with main power switch on. Potentiometer SPST switch is reading 17K ohms when off and then goes to 0 ohms when on. The pot resistor that controls the speed varies as expected from near 0 ohms to 10K ohms at full speed. The 17K seems low for an open circuit and may not allow the safety circuits to operate correctly. All measurements are made connected to the circuit board. So circuit board could be influencing resistance measurements. Not so easy to disconnect from circuit board.

Anyone have experience with the pot on this lathe? Do most think it's the pot? If not then it's likely the control board and may be screwed as parts for this lathe are not available.

I have found 10K pots with SPST switches for cheap enough. I guess I could just try it. Any help would be appreciated.