So, here's the scenario:
I have a typical Gcode file with multiple procedures, drill a hole, mill a profile, mill a pocket etc. I do manual tool changes so I have Mach stop on tool change. So the code is halted on a the tool change line of code. No problem. Usually after changing the tool I need to move the table over to a clear piece of material surface to set the tool zero. Sometimes I also need to move clamps etc. to accommodate the upcoming procedure. Sometimes I need to move it a lot to get a screwdriver in under the head to remove a screw that was being used to hold a piece down. You name it. Still no problem.
The problem comes when I press start after the tool change. Mach insists on returning to the position it was at when it finished the last procedure before it turns around and goes to the location spelled out in the code for the next procedure. Makes no difference if you manually put the cutter right over the position of the next procedure. It still moves back to the previous location first.
It does this at G0 speed as well. This return move is not part of the code it's just something Mach wants to do. It also does it with a combined X,Y and Z move so even if I have a proper rapid clearance for clamps etc. It can still hit clamps because it does not do the Z move first and independently.
Sorry I can't give you any code file to replicate this because it's not in the code. It's something Mach does on it's own.
Anyone can emulate it by doing what I've described.
Stop on tool change
Move the table around while it's stopped
Leave it anywhere you like
Start the code again and see where it goes first. It will be to the last position it was at and then immediately to the position in the next line of code. No stops.
It's a bit dangerous, I think, and there is no real good reason for it (that I can see).
Sage