Cutter compensation offsets the tool from the programmed path by its radius, so you can program the finished part edge and let the control account for the actual tool size. Change tools or regrind and you only update the offset, not the program.
| Code | Action |
|---|---|
| G40 | Cancel compensation |
| G41 | Compensate left of the path |
| G42 | Compensate right of the path |
How it works
- G41/G42 reference a diameter or radius offset register, usually called with a D word.
- Engage and cancel compensation on a straight lead-in or lead-out move, never inside an arc.
- Left or right is judged looking in the direction of travel.
G41 D01 X0.0 Y0.0 (turn on, comp left)
G40 X-0.5 (cancel on the way out)
G40 X-0.5 (cancel on the way out)
FAQ
What’s the practical benefit of using cutter compensation instead of programming the exact tool path? Cutter compensation lets you program the actual part geometry rather than calculating an offset toolpath by hand, and lets you adjust for a different actual tool diameter, from wear or a tool change, just by changing the offset value, without reprogramming the path.
Related: plane selection.