I have just got off the phone with Tech support at Palmgren for the head unit of a 351.217170 Craftsman lathe. So far, they have been great with trouble shooting of the situation. I have been able to check on what they need to know and they are pulling manuals to find the electronic values so I can trouble shoot some more. I think we have narrowed it down to the circuit board. I was surprised to find out the motor was DC and the variable speed was an actual motor speed control not a slip pully system. There may be help yet. I know there have been negative reports of this lathe and the company, I just wanted people to know something positive is happening. 