Originally Posted by
adamvs
Taking test cuts is the only *real* way to get an accurate work offset on the lathe. Using switches for homing, I think, is one of the side effects of the fact the tool is open-loop. You can get really pretty close using a known diameter and the piece of paper method, but coding up a test cut on your master tool in conversational, is very fast. Takes a minute or two, then you're good to go. Getting very accurate diameters on a tool other than the master tool is a little more complicated. One of subtle items is backlash, so it depends how the cut is being approached by the tool in question. Eg, if you calibrate the tool moving toward X-, but cut moving toward X+, you're going to off by the backlash amount. This is one of the frustrating things I've found using Fusion360. It'll generate a toolpath going front to back, but sometimes *not* going back to front ( ?1? ), which might reverse the direction the cut is approached from.