What is the normal procedure on a lathe with an autochanger for tools, as far as head position and tool offsets are concerned.

I'm trying to get my head around programming a TCL160 for use with a Planet-CNC board.

As the tools stick out of the turret quite a way, I need to send the turret to a known safe location before rotating the turret to load a new tool.

At the moment, this is working fine, but when I activate the gcode tool selection command eg T3, the head moves to take up the newly offset position.

I can see that the lathe needs to enforce this offset at some point, but I'm surprised that it is when the tool is selected, and not at the next movement command.

When would Mach3 or Eding enforce the tool offset ?

Adrian.