Quote Originally Posted by threesixesinarow View Post
My 7x10 has a poly-vee belt drive now, with a 6-rib J-section belt to the headstock countershaft running on a pair of 1-1/4” pulleys. It hasn’t slipped but my collets only take up to 9/16”, so it’s hard to compare.

My mill has 3-rib J belts on slightly bigger pulleys and in low gear they can slip, even with just a 350W motor.
Interesting. My mini mill (500 watt) has never slipped. It uses a timing belt also but it is much wider than the lathe belt and I think it is a 5mm pitch.
Cheers, JR