Discover how CNC G-code commands like G64 and G01 help eliminate vibration and improve surface finish when milling sharp corners.
The Challenge of Sharp Corners in CNC Milling
When a CNC machine hits a 90-degree corner, the physical inertia of the tool can cause "overshooting" or vibration. To achieve a smooth milling finish, we must instruct the controller on how to handle these directional changes.
Key G-code Commands for Corner Smoothing
1. G64: Constant Velocity Mode
The G64 command is the most common way to maintain feed rate. Instead of stopping exactly at the coordinate, the machine blends the path slightly to keep the motion fluid.
2. G61: Exact Stop Mode
Contrary to G64, G61 ensures the machine reaches the exact coordinate before moving to the next line. This is used for high-precision parts where sharp corners are non-negotiable, though it increases cycle time.
3. G02/G03: Adding Fillets
Sometimes the best way to smooth sharp corners in milling is to replace them with a tiny radius using circular interpolation commands (G02/G03).
Example G-code Snippet
G01 X50.0 Y0.0 F500 ; Move to corner
G64 P0.1 ; Set blending tolerance to 0.1mm
G01 X50.0 Y50.0 ; Turn corner smoothly
