CNC Machinist Calculator UltraG39 Corner offset circular interpolation
Fanuc G-code · Mill
In cutter compensation mode, inserts an arc with the tool radius at an outside corner so the tool rolls around it instead of making a sharp point.
Verify on your machine. This entry could not be fully checked against the maker manual. Check your machine manual before you run it.
Format
G39 [I J K]
Addresses
| Address | What it does |
|---|---|
I J K | Optional vector that sets the direction of the next move for the corner |
How it works
One shot, group 00. Works only with G41 or G42 active.
Example program
G41 D08 G01 X0. Y0. F20. (COMP ON)
X2. (FIRST SIDE)
G39 (ROLL AROUND CORNER)
Y1. (SECOND SIDE)
…
X2. (FIRST SIDE)
G39 (ROLL AROUND CORNER)
Y1. (SECOND SIDE)
…
The full 5-line example is in the app. Example is in inch. Check offsets and clearances first.
Watch out for
- Give G39 in its own block between the two moves that form the corner.
- Many programmers simply program an arc instead.
Related codes
G39 on other controls
The same number can mean something different on another control.
| Control | Meaning |
|---|---|
| Fagor 8055 8065 | Automatic chamfer |
Every G-code for Fanuc in your pocket. The app has the full example programs, search by number or shop word, a line decoder and calculators for tapping, threading and drilling.
Open G39 in the app All Fanuc G-codes