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M04 Spindle on counterclockwise / Spindle on reverse
Haas NGC M-code · Mill, Lathe
On mills: Spindle on counterclockwise
Starts the spindle counterclockwise at the S speed. Used for left hand tools.
Format
M04 S
Addresses
| Address | What it does |
|---|---|
S | Spindle speed in RPM |
How it works
Modal, stays on until M03, M05, M00, M30 or a tool change.
Example program
T9 M06 (LEFT HAND TOOL)
G90 G54 G00 X0. Y0. S1500 M04 (SPINDLE ON CCW)
G43 H09 Z1. (LENGTH COMP)
G90 G54 G00 X0. Y0. S1500 M04 (SPINDLE ON CCW)
G43 H09 Z1. (LENGTH COMP)
Example is in inch. Check offsets and clearances first.
Watch out for
- Right hand tools run in M04 rub and break. Check the tool before using M04.
- G74 and G84 control spindle direction themselves.
On lathes: Spindle on reverse
Starts the main spindle in reverse at the S speed. Used for tools mounted upside down or back side work.
Format
M04 [S]
Addresses
| Address | What it does |
|---|---|
S | Spindle speed |
How it works
Modal until M03 or M05.
Example program
T0202 (UPSIDE DOWN OD TOOL)
G97 S1200 M04 (SPINDLE REVERSE 1200 RPM)
G00 G54 X2.1 Z.1 (APPROACH)
G97 S1200 M04 (SPINDLE REVERSE 1200 RPM)
G00 G54 X2.1 Z.1 (APPROACH)
Example is in inch. Check offsets and clearances first.
Watch out for
- Check the insert orientation. Reverse with a right hand tool rubs and chips the insert.
Related codes
M04 on other controls
The same number can mean something different on another control.
| Control | Meaning |
|---|---|
| Fanuc | Spindle on, reverse |
| Doosan (Fanuc) | Left spindle reverse rotation |
| DMG Mori MAPPS (Fanuc) | Spindle start(reverse) |
| Mazak (EIA) | Spindle reverse rotation |
| Okuma OSP | Spindle counter clockwise (Lathes & Mills) |
| Mitsubishi M70 M80 | Spindle on counterclockwise |
| Brother Speedio | Spindle on counterclockwise |
| Siemens 840D 828D | Spindle on counterclockwise |
| Heidenhain TNC (ISO) | Spindle on counterclockwise |
| Fagor 8055 8065 | Spindle counterclockwise |
| LinuxCNC Tormach | Spindle counterclockwise |
| Mach3 Mach4 | Spindle on counterclockwise |
| Centroid CNC12 Acorn | Spindle on counterclockwise |
| Hurco WinMax (NC) | Spindle on counterclockwise |
| Fadal | Spindle on counterclockwise |
| Swiss (Citizen Star) | Main spindle reverse |
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