M154/M155: Engage/disengage C axis

Engages or disengages the C axis on mill-turn machines depending on the builder.

For reference only: syntax changes with the control, the post-processor and the machine parameters. Check the official manual and run a simulation before cutting. Legal notice.

Family: Mill-turn
Machine: Turning, Mill-turn
Risk: High
Example: M154 / M155

M154/M155

Mill-turn

Engage/disengage C axis

E.g.:

M154 / M155

Machine: Turning, Mill-turnRisk: High

Haas · Fanuc

Haas: Common on Haas lathe with C axis; confirm brake/orientation.
Fanuc: Depends on the MTB/PLC.

Other codes in Mill-turn

M133/M134/M135 motorized lathe tool Fanuc G50.2/G51.2 Polygon turning

See the full list of G and M codes

Frequently Asked Questions (FAQ)

What does M154/M155 mean in a CNC program?

Engages or disengages the C axis on mill-turn machines depending on the builder. In the catalogue it appears as "Engage/disengage C axis", within the Mill-turn family.

Can you give me an example of M154/M155?

M154 / M155 — Engages or disengages the C axis on mill-turn machines depending on the builder.

Which machines use M154/M155?

M154/M155 is used in: Turning, Mill-turn.

What should you watch out for with M154/M155?

High risk: a mistake here can cause a crash, a broken tool or an out-of-tolerance part. Simulate the program and dry-run it before cutting.

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