G27: Reference return check
Checks if the axis reaches the programmed reference position.
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
- References
- Machine
- Milling, Turning, Mill-turn
- Risk
- Medium
- Example
- G27 X0 Y0 Z0
G27 X0 Y0 Z0Machine: Milling, Turning, Mill-turnRisk: Medium
Fanuc
G27 X... Y... Z...- Different from G28/G30; used for return verification.
Haas
- Confirm behavior of alarms and included axes.
Other codes in References
See the full list of G and M codesFrequently Asked Questions (FAQ)
What does G27 mean in a CNC program?
Checks if the axis reaches the programmed reference position. In the catalogue it appears as "Reference return check", within the References family.
How is G27 written on each control?
Fanuc: G27 X... Y... Z.... The exact syntax depends on the control version and the machine parameters: always confirm with the manufacturer's manual.
Can you give me an example of G27?
G27 X0 Y0 Z0 — Checks if the axis reaches the programmed reference position.
Which machines use G27?
G27 is used in: Milling, Turning, Mill-turn.
What should you watch out for with G27?
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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