M41/M42: Low/high spindle gear range

Selects the low or high mechanical spindle gear range on machines with a gearbox.

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: Spindle
Machine: Milling, Turning, Mill-turn
Risk: Medium
Example: M41 / M42

M41/M42

Spindle

Low/high spindle gear range

E.g.:

M41 / M42

Machine: Milling, Turning, Mill-turnRisk: Medium

Fanuc · Haas

Fanuc: Machine dependent; it may require the spindle to stop.
Haas: Low gear/high gear on compatible machines.

Other codes in Spindle

G96/G97 Constant speed / fixed RPM M19 Spindle orientation M38/M39 Spindle speed variation G25/G26 Spindle speed fluctuation detection

See the full list of G and M codes

Frequently Asked Questions (FAQ)

What does M41/M42 mean in a CNC program?

Selects the low or high mechanical spindle gear range on machines with a gearbox. In the catalogue it appears as "Low/high spindle gear range", within the Spindle family.

Can you give me an example of M41/M42?

M41 / M42 — Selects the low or high mechanical spindle gear range on machines with a gearbox.

Which machines use M41/M42?

M41/M42 is used in: Milling, Turning, Mill-turn.

What should you watch out for with M41/M42?

Medium risk: it rarely breaks anything on its own, but a wrong value shows up on the part. Check the block before running the batch.

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