Was turning this afternoon and the live center started to make a low whirring noise. I stopped immediately. Pulled the live center and it does not feel that it turns rough, and seems very tight. I have no idea what brand it may be, it came with my 40 yr old Rockwell lathe (46-525) I has interchangeable centers which I like a lot. There does not appear to be a hole to get oil into the bearings from the back or sides. There is a hole of some kind in the center of the socket where the removeable points go. How do you lube the bearings and what lube to use?