re: PDM-30 nut stripped; I bought a PDM30 from a fellow and indeed the nut AND the leadscrew are worn to the point of excessive play. Mind me asking where you bought your parts from? KMS sells the machine but gave me the 'after warranty period, its not our problem' speech and I've tried a few King Canada depots but the prices are crazy....$138 + shipping for the nut and another $342 for the lead screw...