G2: clockwise arcs
G2 cuts a clockwise arc from the current position to X and Y, turning around the centre given by I and J. It is the best understood command in the converter: the reference program is a single contour made of forty-nine G2 arcs.
Syntax
G2 X<mm> Y<mm> I<mm> J<mm> [V<feed>]VerifiedReproduced byte for byte from a machine-proven file.
Parameters
X | X coordinate of the end point in millimetres | required |
Y | Y coordinate of the end point in millimetres | required |
I | X coordinate of the arc centre | required |
J | Y coordinate of the arc centre | required |
V | Feed rate | optional |
How it is written to PGM
A clockwise arc becomes a record of 28 bytes: six of framing, the end point, the working depth where it changes, the centre as absolute I and J, and the feed class on the first cut of a path. The centre is absolute, not an offset from the start.
Example
G2 X492.812 Y214.536 I301.030 J221.047 V600Notes
- All four of X, Y, I and J are required. A missing one is a parse error.
- Coordinates are absolute millimetres; the centre is absolute as well, not relative to the start of the arc.
- A feed rate V is accepted and appears on the first cutting move of the reference program.
Messages this command can produce
- Arc without a centreParse error
- Cutting before any depth was setUnsupported
- Depth change after the first depthUnverified
- Coordinate out of rangeParse error