Where is G68?

Hello. I'm just migrating here from Mach3.

I do a lot of work where a part is fixed to the machine bed arbitrarily.
In Mach, I would use a wizard that let me touch off two points and it would rotate the coordinate system (around the z axis) to the part. This would result in perfect alignment every time.

G68 seems to be a good code to do this manually but it doesn't seem to exist in LinuxCNC at all?!?!? ("Unknown G Code used")

- Noob question? How to rotate the fixture with G-code without G68?
- Better yet, is there a tool, macro, add-on, plugin etc that would automate this for me (doing trig angle math every time seems ridiculous)?

Thanks in advance!

I have made my own probing routine which is to weird to post here, but you could search for 'probe screen' , and get a graphical interface.

otherwise by probing with G38.2, calculate with Atan, which is actually Atan2, set rotation by

G10 L2 P coordinatesystem number R rotation

I am fairly sure that JT mentioned how he did a similar thing to straighten up the work on sheets on the plasma.

Now I wonder if I can find it?

andypugh wrote: I am fairly sure that JT mentioned how he did a similar thing to straighten up the work on sheets on the plasma.

Now I wonder if I can find it?

Andy its in a zip file here
gnipsel.com/linuxcnc/examples.html

I followed JT's example a while back and added the buttons to a PyVCP panel. Looking at the subroutine code I see I had commented out the G92 calls in align-x and align-y. I had an issue with that but don't remember the details now. It works well and the G10 L2 is the important part. There are four buttons. '1. Align Start', '2. Align Y', 2. Align X', and 'Clear Offset'.