I've been asking myself this question for a while and don't exactly know at what point does one need to move from a dead center to a live center? Is it because with a live center you can put more pressure to the center of the workpiece and therefore cut more precisely? or does it have something to do with the size of the workpiece? If you use a well lubed dead center and there's no sign of the tip overheating, why would you use a live center than? could you explain that for me. Does the live center always go in the headstock?