Cycle Syntax
G90 X... Z... I...;
X: Diameter to be cut.
Z: End point in Z-axis.
I or R: Distance and direction of taper (Radius value).
Q: Angle on the starting point (if supported).
F: Feedrate (optional in some controls).
Incremental Values
You can use incremental values like U and W instead of X and Z.
G90 U... W...
U: X-axis incremental distance to target.
W: Z-axis incremental distance to target.
How it Works
G90 is a rough turning cycle used for straight or taper cutting. You give the endpoint (X/Z) and optionally I or R for taper. Each subsequent X value creates another pass. The cycle cancels only with another motion command.
Example Program
G30 U0 W0;
G50 S2000 T0100;
G96 S200 M03;
G00 X56.0 Z2.0 T0101 M08;
G90 X51.0 W-32.0 F0.25;
X46.0;
X41.0;
X36.0;
X31.0;
X30.0;
G30 U0 W0;
M30;
G50 S2000 T0100;
G96 S200 M03;
G00 X56.0 Z2.0 T0101 M08;
G90 X51.0 W-32.0 F0.25;
X46.0;
X41.0;
X36.0;
X31.0;
X30.0;
G30 U0 W0;
M30;
🔸 G90 stays active until canceled by another motion command like G00 or G01
🔹 Used for straight turning, taper turning, and boring
🔸 I or R used for taper, depending on CNC control type
🔹 Always return to home using G30 or G28 after turning
🔹 Used for straight turning, taper turning, and boring
🔸 I or R used for taper, depending on CNC control type
🔹 Always return to home using G30 or G28 after turning