G8 Lathe radius mode

LinuxCNC Tormach G-code · Lathe

Makes X words read as radius on a lathe. X1 puts the tool 1 inch from center, a 2.0 inch diameter.

Format

Addresses

Address	What it does
`none`	No words

How it works

Modal. Default at power up in stock LinuxCNC. Stays on until G7.

Example program

G20 G18 G8 G90 (INCH, XZ PLANE, RADIUS MODE)
T1 M6 G43 (TURNING TOOL)
G97 S1200 M3
G0 X0.525 Z0.1 (RADIUS .525 IS 1.05 DIAMETER)
…

The full 5-line example is in the app. Example is in inch. Check offsets and clearances first.

Watch out for

Check the mode before running a program written for another lathe. A wrong mode doubles or halves X.
Some cycle words such as G76 I J K follow the mode. Check the cycle notes.

Related codes

G7 · G18

G8 on other controls

The same number can mean something different on another control.

Control	Meaning
Fanuc	Advanced preview control
Fagor 8055 8065	Arc tangent to previous path
Fadal	Accelerate, no feed ramps

Every G-code for LinuxCNC Tormach in your pocket. The app has the full example programs, search by number or shop word, a line decoder and calculators for tapping, threading and drilling.

Open G8 in the app All LinuxCNC Tormach G-codes

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