LinuxCNC G5.3

G5.3 is the LinuxCNC G-code that closes a NURBS data block. It is programmed on its own line after a G5.2 block, and the lines between G5.2 and G5.3 define the curve control points together with their weights (P) and the parameter L that sets the curve order. G5.3 takes no axis words or other arguments.

Source checked3/3 values · 2026-10-26

Specification

1 source

Language	gcode
Code	G5.3
Group	NURBS block
Syntax	G5.3
Dialect	LinuxCNC

Study notes

G5.2 opens the NURBS data block and G5.3 closes it; the control points are written on the lines between the two codes.
Each control point line can carry a weight P and the parameter L, which determines the order of the curve.
The current coordinate before the first G5.2 command is always taken as the first NURBS control point.
Default weight is 1 when P is unspecified; default order is 3 when L is unspecified.
The NURBS block section gives a G0/F10/G5.2 ... G5.3 example followed by an M2 program end.

Safety

G5.2 and G5.3 are documented as experimental and not fully tested.