Can't figure out Lightburn positions

already looked at some of the videos about origin, maybe I need to rewatch them again cuz I can’t tell what Lightburn will do.

I set my machine at the zero position so it can start off squared. start Lightburn and open my project which has already been saved by lightburn once. my objects already placed where I want them and an image also. I use frame to see where it will raster the image so I can do some tests for settings. laser stops at the corner where the image is located. once I click start the laser moves back to another origin and comes back to raster the image but is now offset by around 120mm for no apparent reason.

Just tried doing it again with a new project and now it gives me the error that I might be out of bounds, even though it did the frame. start the job anyway and still it offset.

Trying setting the “Start From” to" Current position" instead of “User origin” and see if that helps.

As for the Out Of Bounds, when you do a frame it traces around the bounding box of your work, but when you do a raster scan the laser head has to travel quite a bit outside of that bounding box so it has room to accelerate & decelerate. That extra travel is probably putting you out of bounds. Move your work a little farther from the edge.

You may need the $10 setting to be 0. Setting it to 1 is reporting machine absolute coordinates. If the machine has limit switches and homes on power on or startup, it doesn’t matter. If you home it manually, it likely does matter. You’ll be able to tell by looking at what “Get Positions” gives you - if it reports accurately where the laser head is, you’re good. If it’s giving you strange numbers, that setting will be why.

It’s also possible that the incorrect positioning is from missing motor steps. Your profile just says “DIY CO2” - is this a new setup that still may need tuning, or is it relatively proven at this point?

before I stopped messing with it I did try absolute coordinates instead of user origin and it didn’t give me the out of bounds error anymore.

I’ve used the machine successfully with other software, so I don’t believe its missing steps. I’ve been able to make some repeatable cuts with LB also. It’s just that offset that occurs.
I’ll try changing that setting to see what happens

seems to work better now with absolute coordinates selected. haven’t had an offset so far

You might just need to read up on how the user origin / current position stuff works with the Job Origin setting. It’s standard stuff for CO2 lasers, but less common for GCode systems:

Hopefully that helps.

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