CNC Machinist Calculator UltraG42 Cutter compensation right / Tool nose radius compensation right
Fanuc G-code · Mill, Lathe
On mills: Cutter compensation right
Offsets the tool to the right of the programmed path, looking in the direction of travel, by the radius in offset D. With a right hand tool this is conventional milling.
Format
Addresses
| Address | What it does |
|---|---|
D | Offset number holding the tool radius |
X Y | Lead in move that starts compensation |
F | Feed rate |
How it works
Modal, group 07. Cancel with G40.
Example program
G01 Z-.25 F10. (DEPTH)
G42 D08 Y0. F20. (COMP ON, LEAD IN)
X3. (CONVENTIONAL CUT BOTTOM SIDE)
…
The full 5-line example is in the app. Example is in inch. Check offsets and clearances first.
Watch out for
- Same start and cancel rules as G41. Use a straight lead in and lead out.
- A negative D value switches the side, so G42 with minus D acts like G41.
On lathes: Tool nose radius compensation right
Offsets the path to the right of the direction of travel by the nose radius. Normal for OD turning toward the chuck. Radius and tip direction come from the offset called by T.
Format
Addresses
| Address | What it does |
|---|---|
X Z | First move, used to bring compensation in |
How it works
Modal, group 07. Cancel with G40.
Example program
G96 S600 M03 (CSS)
G00 X.6 Z.1 M08 (APPROACH)
G42 G01 Z0 F.006 (COMP ON)
…
The full 7-line example is in the app. Example is in inch. Check offsets and clearances first.
Watch out for
- A standard OD turning tool is usually tip 3. Enter R and T on the offset page.
- Without compensation, tapers and radii come out wrong by part of the nose radius.
- Bring it on with a move off the part, not on the first cutting move.
Related codes
G42 on other controls
The same number can mean something different on another control.
| Control | Meaning |
|---|---|
| Haas NGC | Cutter compensation right |
| Mazak (EIA) | Cutter radius compensation right |
| Okuma OSP | Cutter radius compensation right |
| Mitsubishi M70 M80 | Cutter radius comp right |
| Brother Speedio | Cutter compensation right |
| Siemens 840D 828D | Tool radius compensation right |
| Heidenhain TNC (ISO) | Radius compensation right |
| Fagor 8055 8065 | Tool radius compensation right |
| LinuxCNC Tormach | Cutter compensation right |
| Mach3 Mach4 | Cutter comp right |
| Centroid CNC12 Acorn | Cutter compensation right |
| Hurco WinMax (NC) | Cutter compensation right |
| Fadal | Cutter radius compensation right, conventional |
| Swiss (Citizen Star) | Nose radius compensation right |
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Open G42 in the app All Fanuc G-codes