How to Set Work Offset in CNC: Simple Guide

To set a work offset in CNC, use the G54 to G59 codes to define different coordinate systems relative to the machine zero. You set the offset by moving the tool to the desired position and then storing that position as the work offset using the machine controls or programming commands.

Syntax

Work offsets in CNC are set using the codes G54 through G59. Each code represents a different coordinate system offset from the machine zero.

• G54 - Work Offset 1
• G55 - Work Offset 2
• G56 - Work Offset 3
• G57 - Work Offset 4
• G58 - Work Offset 5
• G59 - Work Offset 6

To set a work offset, you typically jog the tool to the desired position and then use the machine's control panel or a program command to save that position as the offset.

gcode

G54
G55
G56
G57
G58
G59

Example

This example shows how to select the G54 work offset and move the tool to a position relative to that offset.

gcode

G54
G0 X0 Y0 Z0 ; Move to the origin of work offset G54
G1 X10 Y10 Z-5 F100 ; Move to X10 Y10 Z-5 at feed rate 100

Output

Tool moves to the origin of the G54 offset, then moves to X=10, Y=10, Z=-5 relative to that offset.

Common Pitfalls

Common mistakes when setting work offsets include:

• Not zeroing the tool at the correct physical location before setting the offset.
• Forgetting to select the correct work offset code (G54 to G59) before running the program.
• Overwriting offsets unintentionally by setting them without confirming the current offset.
• Confusing machine zero with work offset zero.

Always verify offsets with a dry run or manual check before full machining.

gcode

Wrong:
G0 X0 Y0 Z0 ; Moves to machine zero, not work offset

Right:
G54
G0 X0 Y0 Z0 ; Moves to work offset zero

Quick Reference

Work Offset Code	Description
G54	Work Offset 1 (default)
G55	Work Offset 2
G56	Work Offset 3
G57	Work Offset 4
G58	Work Offset 5
G59	Work Offset 6

Key Takeaways

Use G54 to G59 codes to select different work offsets in CNC programming.

Set work offsets by moving the tool to the desired position and saving that position as the offset.

Always confirm you are using the correct offset before running your CNC program.

Avoid confusing machine zero with work offset zero to prevent machining errors.

Verify offsets with a dry run or manual check before full operation.