Enabling G55 workspace in Grbl header

I’m am very new to Lightburn (like as of today). My current workflow in the CNC world is to use workspace G55 for all of my laser toolpathing. (G54 is reserved for CNC carving toolpaths allowing me, for one thing, to keep X0Y0 separate across multiple workspaces.) I cannot find a way in LightBurn to enable G55 workspace as the software inserts the following line in the header of every gcode file “G00 G17 G40 G21 G54”. Using the user supplied start block code doesn’t work as the default header line is installed under the user supplied code block. I tried to create a “Custom GCode” device but even in that configuration in which nearly all of the gcode lines are configurable the default header line (with the G54) command is automatically inserted following the configured start block. I can’t find any way to edit the default code block. Am I missing something or is this just the way it is.

You can try manually create a CUSTOM GCODE profile and then tinkering with the options to see what you get.

That header is hardcoded into our generation. We do not have a way to switch workspaces currently.

A different way of going about it would be using a tool offset using G10 for your laser rather than an entirely different workspace.

What kind of CNC control are you running?

I tried using the custom header option and the CUSTOM GCODE profile. The problem is that the hardcoded header with the G54 command is inserted into the final gcode file AFTER the custom header thus overriding the G55 command I’m trying to employ. I’m curious as to the thought process in terms of coding this function that gives the user the option of providing a custom Start code block but then inserting the uneditable header AFTER that start block instead of before it and truly giving the user the options to override commands in the default header. I could certainly use the G10 offset command (and may need to as there are aspect of LightBurn that I really like and would like to use). Unfortunately, that deviates from my standard workflow of separating the laser toolpaths into its own workspace which I’ve kind of gotten used to. Anyway, thanks for the responses.

Could you maybe save as Gcode, and copy the top lines of code here

And then edit them to what they would need to BE to work on your setup?

That way we all will be in the same path :slight_smile:

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Honestly the thought process wasn’t there.

Custom g-code is quite literally in it’s infancy and we are interested to see how people use it and what needs to change to make it better. I think this is a good example.

I am going to make a feature request for this now. Thanks for your feedback.

Can you show me what your current work flow was and maybe the cam that you were using that enabled it?

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Thanks Joe. I appreciate the response. Primarily, my laser use is in hybrid projects involving CNC machining on wood with laser engraving overlay. In order to keep things in order I use G54 for CNC machining and G55 for laser etching (which helps me keep my X0Y0 settings separate). I use Vectric Aspire as my design software and that platform allows for multiple post-processors to be used across different applications. As such I have a custom post processor for machining that includes a G54 command and a separate custom post processor for the laser etching that includes the G55 command. I use two different power diode lasers that each involve a different offset from the CNC X0Y0 so using the G10 command for putting the laser offset into the gcode file is not too feasible. I have used a standalone 40W C02 laser for separate laser cutting/etching applications but have moved to using my 44w diode laser on my CNC frame for these operations. It is for these laser only operations that I really want to be able to use LightBurn as its laser-specific features will work better in these applications that Aspire. I can certainly work around the inability to add the G55 command in the LightBurn gcode but it will be helpful to me (from a consistency standpoint) is and when that feature is enabled.

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For me I would modify your laser post to catch specific tool numbers for your different laser modules and dump a G10 in accordingly. :slight_smile: I used to write posts for a living though haha.

This is something we are planning to directly support in MillMage so it’s interesting to hear from someone doing this. Can I ask you a thousand probing questions? I have a couple to start…

1- Why do you want your work offsets separate? I would think that since you have machined the objects you lasered and have them fixtured still it would be advantageous to keep the work coords consistent for alignment. (obviously this is less useful if you are bouncing between control software)

2- If you CAM software let you program these all together and output it as one program with a tool offset swap and you could hit go and have everything run in order (like CNC features-Laser Logo-CNC cutout), is that interesting to you?