Misaligned layers

I know you’ve all heard it before and I apologize but I’ve seen this problem from many users here but haven’t found an answer as to why it’s happening. I’ve had this misalignment problem with layers since day one. With smaller engravings it not an issue, but larger burns are a nightmare.
Files were created in Inkscape and ran in lightburn. I don’t know if it’s a software issue or my machine. My belts are good, no crud build up anywhere in the belts or gears, everything is oiled properly…etc.

I’m running newest Ruida controller, laser is a Bodor 1309.

Everything is lined up perfectly in the software, I run my fill layers then cut the holes…holes are misaligned…again.
I’d seriously pay someone to walk me through this…I don’t have the time or money to continually throw away ruined material.
Please see images below.
Notice the lines and outline…these were all on one layer…fill + line…the outline is misaligned.
The last layer was the holes…they’re way off, but not every single hole, some areas were acceptable. And no, the piece did not move during the burn.
Thank you in advance for any input you may have.

Your steppers are slipping, likely because of optimistic speed or acceleration settings.

Go to Edit > Machine Settings, and look at the following values (these are mine, yours will be different):

Take a screen shot of the values you have now, and post it along with the size of your machine (1300 x 900?). Drop the highlighted values by about 25% and try running the same job again. If it still slips, drop another 25%, but I suspect the first will be enough.

Awesome Oz! I’ll try that first thing in the morning and post back. I finally got in touch with a Bodor tech …he said Ruidas don’t support svg or other software without issue…I told him thousands of ppl run lightburn and svg.
I’ll check back in the AM!
Appreciate your help!

Couldn’t wait until tomorrow…this is driving me crazy. See photo of my factory settings. Yes…1300 x 900
Thanks again Oz

I haven’t changed any settings yet but here’s what I’ve found.
The laser head seems to drift down on y and left on x as it goes from layer to layer.
If I was to stop and reset the machine between each layer it will work ok.
If I run the whole file straight though, when the file is complete and returns home, it is so out of whack, the hard limit warning comes on…it’s trying to zero beyond its limit switch parameters…if that makes any sense?

Does it shift or skew when you do scans? Like, if you engrave a square, does it slant? You’re speed and acceleration settings are already quite low - you might have a bad motor driver. Can you show your engraving acceleration values too?

And to make the techs there happy, it would be a simple matter to load the same file into RDWorks and run it, to see if you get any slipping.

No shifting or skew issues, Oz.

There are X and Y backlash values programmed - Try zeroing those. They make the motion system dead-stop, and could conceivably cause trouble. If it makes no difference you can put them back.

Well…I installed rdworks, converted the file to dxf, ran it in rdworks and everything is perfect.
I can’t stand the program and would WAY rather use lightburn. Is there anything else anyone can suggest?
I did not try running lightburn in dxf format, I’ve always used svg from Inkscape…not sure if that would make a difference??
I was told by tech support that ruida is designed for dxf (and other formats but not svg) and for use in rdworks only.
There’s gotta be thousands of people running lightburn with ruidas…I can’t be the only one with these issues.

Checked gantry to ensure it is square with the rails, it’s perfect. I did notice that the right belt on the x axis is slightly looser than the left belt, I can’t see that being the issue tho if everything is fine in rdworks.

Ruida is aware of LightBurn, and has conversations with me, supporting what we’re doing (to my face, at least) because it helps them sell more hardware. “Designed for DXF” is a completely asinine statement given that RDWorks supports PLT files and AI files as well as DXF, and doesn’t handle half the DXF format properly (try using a file with nested block inserts in RDWorks - it fails). Everything sent to the controller is line segments by the time it gets there - the controller has no idea what file format it came from.

Do you have an option called ‘backlash repay optim’ enabled on the User tab in RDWorks? That’s the only thing I can think of that would possibly make a difference. There is also a ‘Small circle speed limit’ value that can be set in the Config > System Setting menu in RD. Check for that too.

Can you send an email to developer at lightburnsoftware dot com with a link to this thread? I’d like to take a look at the file you’re running (the LBRN file) and have you send a .RD file output from LightBurn, along with one of the same job from RDWorks (save to UFile). I’ll compare them to see if there are any odd commands in the RD version that could explain the difference.

I would totally appreciate that Oz.
As I said, I’ll gladly pay you for your time…anything to keep lightburn going.
I have to run out for a bit here, but will check out what you asked and get you those files as soon as I return!
Thanks Oz!

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