G51/G50: Scale/scale cancellation

Applies scale to the program or cancels the active scale 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: Coordinate equivalences
Machine: Milling, Mill-turn
Risk: High
Example: G51 X0 Y0 P0.5 / G50

G51/G50

Coordinate equivalences

Scale/scale cancellation

E.g.:

G51 X0 Y0 P0.5 / G50

Parameters

X Y Z: Centro de escalado. · mm
P: Factor de escala común a todos los ejes (P0.5 = mitad).I J K en algunos controles escalan cada eje por separado (permiten espejo con valor negativo). G50 cancela.

Machine: Milling, Mill-turnRisk: High

Fanuc

G51 ... / G50

Do not confuse G50 scale with G50 RPM limit around, depends on context/control.

Haas

G51 / G50

It can depend on installed options and settings.

Siemens · Fagor

Siemens: Siemens equivalence: SCALE / ASCALE.
Fagor: Fagor equivalence depends on available transformation functions.

Other codes in Coordinate equivalences

G68/G69 Coordinate rotation

See the full list of G and M codes

Frequently Asked Questions (FAQ)

What does G51/G50 mean in a CNC program?

Applies scale to the program or cancels the active scale according to control. In the catalogue it appears as "Scale/scale cancellation", within the Coordinate equivalences family.

How is G51/G50 written on each control?

Fanuc: G51 ... / G50 · Haas: G51 / G50. 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 G51/G50?

G51 X0 Y0 P0.5 / G50 — Applies scale to the program or cancels the active scale according to control.

Which other codes is G51/G50 combined with?

In practice G51/G50 appears alongside these codes: TRANS/ROT/SCALE/MIRROR, G52/G92. It is worth reading them together, because the state one leaves behind conditions what the next one does.

Which machines use G51/G50?

G51/G50 is used in: Milling, Mill-turn.

What should you watch out for with G51/G50?

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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