Lightburn and CNCjs on XXL

I posted this topic over at lightburn, but figured I’d post it here as well, as I am trying to figure out the best practice for this little frustration I have.

I think maybe I’m getting way ahead of myself on my hopes for this but here is my plan.

I have a shapeoko 3 XXL with a Jtech attached. I ran a test using lightburn and all went fine after changing all the settings. However, because of the GRBL settings needing to be changed…well…that’s frustrating. I use CNCjs at the moment to send all the Gcode, and it has a laser module in it that works quite well. Since I can spit the GCode out of Lightburn and just run it from CNCjs without having to change all my settings then I want to do that.
To complicate things, as a long time CNC operator I would prefer to use G54 as my spindle offset, and G55 as my laser offset.
I’m told by lightburn I can not use a G55 command. I did manually change the code and it works fine when run through CNCjs. I’m wondering now, is there a way to tell either Lightburn, or CNCJS what the physical offset is on the laser for the SAME G54 work location. I generally use the same zero point in the front left of the bed located with a corner block for most of my work.

I’ve found lightburn to not be particularly flexible about this sort of thing. What I did was create a macro for “laser mode” and “cnc mode” that resets the origins (milling area into positive space), enabled/disables the grbl laser mode, etc.

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@mikep and @Julien - Do either of you have write-ups or suggested links for setting up your laser, including the type, using macros for going back and forth from CNC etc? Been considering this addition and need to study in detail.

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This video will tell you pretty much all there is to know

For the hardware side of things, I have written a short section about it in v3 of the ebook


The issue I have with all that is it’s exactly the thing in trying NOT to do. To me, the laser is simply another tool, and having to change settings and create macros just to use a tool is a pain, especially if I have to do all that mid-job.
I’m leaning toward just skipping lightburn at this point since I already use Aspire for the CNC, I’ll just set that up with a laser tool and do that. This way all the settings in CNCjs can stay the same and I just have to load the program and go.
The macros may work, but after years of running industrial machines swapping in settings creates a concern of forgetting one and crashing.

Spent a good deal of time reading your ebook this weekend, outstanding effort, thank you! Are you sure English isn’t your native language? Also like the way you’ve incorporated new and educational projects into the ebook in such a timely manner, but isn’t that the point!

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What “$” settings is Lightburn changing?

10, 30, 31, 32. Think that’s the list. Have to check again but think those are all of them. Laser mode and spindle speeds are not necessarily needed to be switched back and forth…unless of course like me you want to run a water cooled spindle AND a laser.

It doesn’t seem to change any, but you need to in order for it to work properly.

Lightburn settings w/ GRBL