CNC Machinist Calculator UltraG03 Circular interpolation counterclockwise / Circular interpolation, counterclockwise
Fanuc G-code · Mill, Lathe
On mills: Circular interpolation counterclockwise
Cuts a counterclockwise arc in the selected plane, viewed from the positive end of the third axis. Same addresses as G02. Climb milling an inside pocket with a right hand tool usually uses G03.
Format
Addresses
| Address | What it does |
|---|---|
X Y Z | End point of the arc |
I J K | Distance from the arc start point to the center in X, Y and Z, always incremental |
R | Arc radius. Plus for 180 degrees or less, minus for more than 180 degrees |
F | Feed rate along the arc |
How it works
Modal, group 01. The plane comes from G17, G18 or G19.
Example program
G43 H02 Z.1 M08 (CLEARANCE)
G01 Z0. F20. (TOP OF PART)
G03 X1. Y0. Z-.1 I-1. J0. F15. (HELIX DOWN .1 PER TURN)
…
The full 6-line example is in the app. Example is in inch. Check offsets and clearances first.
Watch out for
- I J K are always incremental from the arc start to the center.
- Use a minus R only for arcs over 180 degrees. Use I J for a full circle.
- For a helix, add Z to the block. The feed is along the arc path in most setups, check your parameters.
On lathes: Circular interpolation, counterclockwise
Cuts a counterclockwise arc in the ZX plane. Give the end point and either the radius R or the center offset I and K. On OD work toward the chuck, it rounds the outside corner from the face to the diameter.
Format
Addresses
| Address | What it does |
|---|---|
X Z | Arc end point, X as a diameter |
U W | Incremental end point |
I | X distance from start point to center, radius value with sign |
K | Z distance from start point to center, with sign |
R | Arc radius, for arcs up to 180 degrees |
F | Feed rate |
How it works
Modal, group 01.
Example program
G42 G01 Z0 F.006 (COMP ON, FEED TO FACE)
X.75 (FACE OUT)
G03 X1.25 Z-.25 R.25 (.25 CORNER RADIUS, COUNTERCLOCKWISE)
…
The full 6-line example is in the app. Example is in inch. Check offsets and clearances first.
Watch out for
- Read the direction with X plus up on the print. On a front turret lathe it can look reversed from the operator side.
- If start and end radius do not match within tolerance, the control gives an alarm.
- Use tool nose radius compensation for true arc size.
Related codes
G02 · G01 · G17 · G18 · G41 · G42
G03 on other controls
The same number can mean something different on another control.
| Control | Meaning |
|---|---|
| Haas NGC | Circular interpolation counterclockwise |
| Mazak (EIA) | Circular interpolation, counterclockwise |
| Okuma OSP | Circular interpolation counterclockwise |
| Mitsubishi M70 M80 | Circular move counterclockwise |
| Brother Speedio | Circular interpolation counterclockwise |
| Siemens 840D 828D | Circular interpolation counterclockwise |
| Heidenhain TNC (ISO) | Counterclockwise arc, Cartesian |
| Fagor 8055 8065 | Counterclockwise circular interpolation |
| LinuxCNC Tormach | Counterclockwise arc or helix |
| Mach3 Mach4 | Counterclockwise arc |
| Centroid CNC12 Acorn | Counterclockwise arc or helix |
| Hurco WinMax (NC) | Circular or helical move counterclockwise |
| Fadal | Circular interpolation counterclockwise |
| Swiss (Citizen Star) | Circular move counterclockwise |
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