Link to the video:
https://www.youtube.com/watch?v=08qK4NfnXqA---------------------------------------
BTW, I also work differenty than even Gerry. I don't use switches, but, most every thing i make on the mill is a one of a kind, no tool changer for it, etc. So i move to a logical spot where the CAM created a pre-compensated program code, zero / reference the machine, move a little away from the piece and let the chips fly. Thus all coordinates systems are the same.
Not so with the lathe though. Still no home switches on it, do create a home position=machine zero position= tool change position, use work offsets, and do use soft limits to restrict axis movements sometimes.
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What the above implies is that one can setup differently than another user. Yes there are standard ways of doing things.
So it's not theory, but rather an understanding how the controller works along with with what you or a program is telling the controller to do.
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Re-capping on what was said, the controller knows where Machine zero is and then the next step would be to define where the part is so the controller can relate to yet another "grid". Well call that grid, work coordinates and it's grid lies on top of
the machine coordinate grid, located where you told the controller it would be, and, the work coordinates are within
the limits.
RICH