Origin nightmare

Hi everyone, I’ve just spent all evening on this and it’s driving me mad.

Is there a simple technique to just set the origin for a given job?

I need to work with plastic parts of various shapes, and I want to be able to place them on the platen at a convenient location, jog the laser to my chosen reference point, tell LightBurn the laser is at my chosen origin, and then start engraving the design. I’ve tried ‘current position’, ‘user origin’ and ‘absolute coords’, I’ve tried setting the origin, clearing the origin, getting the position, moving from machine zero, and probably every combination of all of them. I can use the ‘position laser’ tool correctly by clicking on a part of my design, so it seems like LightBurn and the CNC agree on where the bits of the design are, but then I start the job and it goes off to start somewhere else every damn time. What am I missing? Why can’t the ‘set origin’ button just, you know, set the origin?!

Set lightburn to User Origin
image

Move laser head to where you want to start cutting from.

PRESS “ORIGIN” ON THE LASER CONTROLLER (on the machine, not in LB) to set that position.

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then run the job.

hope that’s what your missing

Regards, Neil

Based on the profile it looks like OP is on a GRBL device. In that case everything still applies other than pushing the Origin button on the controller.

Use “Set Origin” in Move window to set User Origin.

It seems, though, that OP has tried this without success.

In that case that may be due to unfamiliarity of how this works. I’d suggest watching the LightBurn video that discusses the different Start From modes to see if that clarifies things:
Understanding The Different Start From Modes In LightBurn - YouTube

Thank you both for your replies, and I hope I don’t seem too grumpy. A back injury + an uncomfortable stool + frustrating computer issues do not make for a happy Fezzik unfortunately.

I have a generic 3018 pro, no limit switches at this stage but I just ordered some.

When I hit the “get position” button, I often get something utterly different than when I use the $# command. Shouldn’t they be the same thing? For the life of me I can’t figure out where the machine thinks it is, whether I need to use an offset, what it should be. Seems like I get a different random result every time I try to use the thing, half the time it heads off in the opposite direction to anticipated, crashes into an end, and of course it isn’t helped by all the trial and error and changed settings. I feel like I’m further behind now than when I first turned it on.

From what I can tell, I should home the laser manually to front left before turning on the machine, but when I do this it starts any job by crashing into the left stop.

I’ve watched a few tutorials, but I haven’t found one that troubleshoots this from the ground up.

No. $# shows you work offsets. Get Position shows you the currently reported position. Running ? command shows you status information that includes position information which is more what you want.

Yes. You probably do want to start with the laser at front-left. Are you also using Absolute Coords as the Start From mode in Laser window? It’s the most intuitive method when you’re first starting.

However, you may be dealing with some other issues if you also use your machine for CNC.

Can you start with the machine at front left and then run these commands in Console. Please return output:

$I
$$
$#
?