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M21 Tailstock advance
Haas NGC M-code · Lathe
Moves the tailstock forward to the part using Settings 341 and 342. On ST-10 no settings are used.
Format
M21
How it works
Non-modal.
Example program
G53 X0 (TURRET CLEAR)
M21 (TAILSTOCK TO PART)
T0101 (OD TOOL)
M21 (TAILSTOCK TO PART)
T0101 (OD TOOL)
Example is in inch. Check offsets and clearances first.
Watch out for
- Do not use M21 if the tailstock was positioned by hand. It backs off and repositions and the part can drop.
- Hold pressure is set on the HPU valves, or Setting 241 on ST-40.
Related codes
M21 on other controls
The same number can mean something different on another control.
| Control | Meaning |
|---|---|
| Doosan (Fanuc) | Optional block skip act |
| DMG Mori MAPPS (Fanuc) | External output |
| Mazak (EIA) | Robot service call |
| Okuma OSP | Tailstock Barrier ON |
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