Approach and retract moves in CNC Programming

Introduction

Approach and retract moves help the tool safely reach and leave the workpiece. This avoids crashes and keeps the tool and part safe.

Starting a cut on a new workpiece to move the tool close without touching.

Finishing a cut and moving the tool away safely before stopping.

Changing tools and moving the tool to a safe position.

Avoiding collisions with clamps or fixtures during tool movement.

Syntax

CNC Programming

G00 X... Y... Z... ; Rapid move to approach or retract position
G01 X... Y... Z... F... ; Controlled feed move for cutting or precise approach/retract

G00 is used for fast, non-cutting moves (approach/retract).

G01 is used for cutting moves or slow, controlled approach/retract.

Examples

This example shows retracting the tool up, moving to start, then slowly approaching the part.

CNC Programming

G00 Z5.0 ; Retract tool 5 mm above the part
G00 X10 Y10 ; Move rapidly to start position
G01 Z-1.0 F100 ; Approach the part slowly to start cutting

Retract to a safe height, move home, then approach the part slowly.

CNC Programming

G00 Z10 ; Retract to safe height
G00 X0 Y0 ; Move to home position
G01 Z-2 F50 ; Approach the part for cutting

Sample Program

This program shows a typical approach and retract sequence. The tool lifts up, moves to start, lowers slowly to cut, then lifts up again after cutting.

CNC Programming

G21 ; Set units to millimeters
G90 ; Use absolute positioning

; Retract move - lift tool up safely
G00 Z10

; Move to start position rapidly
G00 X20 Y30

; Approach move - lower tool slowly to start cutting
G01 Z-5 F150

; Cutting move example
G01 X50 Y30 F300

; Retract move - lift tool up after cut
G00 Z10

M30 ; End of program

Important Notes

Always use retract moves to avoid crashing the tool into the part or clamps.

Approach moves should be slow and controlled to prevent tool damage.

Use absolute positioning (G90) to keep moves predictable.

Summary

Approach moves bring the tool safely close to the workpiece.

Retract moves lift the tool away safely after cutting.

Use G00 for fast moves and G01 for slow, controlled moves.