How to Program 5 Axis CNC: Basic Syntax and Example
To program a
5 axis CNC, you write G-code that controls movement along X, Y, Z axes plus two rotational axes (A and B). Use commands like G0 for rapid moves and G1 for controlled cutting, specifying angles for A and B to orient the tool precisely.Syntax
5 axis CNC programming uses standard G-code extended with rotational axes commands:
- X, Y, Z: Linear axis positions
- A, B: Rotational axes angles (degrees)
- G0: Rapid positioning
- G1: Linear interpolation (cutting move)
- F: Feed rate (speed of cutting)
- M codes: Machine functions (e.g., spindle on/off)
Each line commands the machine to move or perform an action, combining linear and rotational moves for complex shapes.
gcode
N10 G0 X0 Y0 Z100 A0 B0 N20 G1 X50 Y50 Z-10 A30 B45 F200 N30 G1 X100 Y0 Z-20 A60 B90 F150 N40 M30
Example
This example moves the tool from a safe height to a cutting position while rotating the tool to specific angles on A and B axes. It demonstrates combined linear and rotational moves for 5 axis machining.
gcode
N10 G0 X0 Y0 Z100 A0 B0 N20 G1 X50 Y50 Z-10 A30 B45 F200 N30 G1 X100 Y0 Z-20 A60 B90 F150 N40 M30
Output
Line 10: Rapid move to X0 Y0 Z100 with A0 B0
Line 20: Cut move to X50 Y50 Z-10 with A30 B45 at feed 200
Line 30: Cut move to X100 Y0 Z-20 with A60 B90 at feed 150
Line 40: Program end
Common Pitfalls
Common mistakes when programming 5 axis CNC include:
- Not coordinating rotational axes with linear moves, causing collisions.
- Using incorrect angle units or exceeding axis limits.
- Forgetting to set safe retract heights before rapid moves.
- Ignoring machine-specific kinematics and limits.
Always simulate the program in CAM software or machine controller before running.
gcode
Wrong: N10 G0 X0 Y0 Z-50 A90 B90 F300 ; Rapid move without safe height Right: N10 G0 X0 Y0 Z100 A0 B0 ; Safe rapid move N20 G1 X0 Y0 Z-50 A90 B90 F300 ; Controlled cut move
Quick Reference
| Command | Description |
|---|---|
| G0 | Rapid positioning (non-cutting move) |
| G1 | Linear interpolation (cutting move) |
| X, Y, Z | Linear axis coordinates |
| A, B | Rotational axis angles in degrees |
| F | Feed rate (speed of cutting) |
| M30 | End of program |
Key Takeaways
Use X, Y, Z for linear moves and A, B for rotational angles in 5 axis CNC programming.
Always include safe retract heights with G0 before cutting moves to avoid collisions.
Simulate your program to check axis coordination and machine limits before running.
Feed rates (F) control cutting speed and must be set appropriately for material and tool.
End programs cleanly with M30 to reset the machine state.