G08/G09: Smoothing and block-wise exact stop

Functions used to activate/deactivate smoothing or require exact stopping in a specific block according to control.

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: Toolpath
Machine: Milling, Turning, Mill-turn
Risk: Medium
Example: G09 G01 X50 F300

G08/G09

Toolpath

Smoothing and block-wise exact stop

E.g.:

G09 G01 X50 F300

Parameters

P: G08 P1 activa el look-ahead (control anticipado); P0 lo desactiva.

Machine: Milling, Turning, Mill-turnRisk: Medium

Fanuc

G09

G09 usually applies exact stop only to the current block.

ISO común · Haas

ISO común: G08 is not universal; it can be smoothing, look-ahead or another function.
Haas: Confirm in Haas manual; Some of the smoothing can be handled with other settings/codes.

Other codes in Toolpath

G61/G64 Exact stop and continuous mode

See the full list of G and M codes

Frequently Asked Questions (FAQ)

What does G08/G09 mean in a CNC program?

Functions used to activate/deactivate smoothing or require exact stopping in a specific block according to control. In the catalogue it appears as "Smoothing and block-wise exact stop", within the Toolpath family.

How is G08/G09 written on each control?

Fanuc: G09. 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 G08/G09?

G09 G01 X50 F300 — Functions used to activate/deactivate smoothing or require exact stopping in a specific block according to control.

Which machines use G08/G09?

G08/G09 is used in: Milling, Turning, Mill-turn.

What should you watch out for with G08/G09?

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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