Problem with Skewed scans

Hope everyone is keeping well!

I have a question for you regarding skewing of an engraving I’m doing on acrylic.

I have setup scan offsets for all my engraving speeds in LightBurn but find I’m getting a slightly skewed out on the lettering and the circle I’ve been trying to engrave.

The diameter of the logo is 125mm, and the scan measures OK left to right and up and down, but skews

about 3 to 4 degrees to the top left, this also applies to the lettering, please see attached.

Has anyone come across this problem?

Is there setting in LightBurn or the controller (Ruida 6445g ) I need to further adjust?

I’ve run the job at 400mm/s and 300mm/s and also with scan offsets off and I get almost the same results.

When I do cutting I get accurate and square cuts.

Any suggestions be appreciated.

Best regards
Ralph
MU logo

Have a look at this thread and see if it fits your situation:

Excessive acceleration can also cause the steppers to loose a step during direction change, but I would start with the link above.

Thanks Hank
I’ll try your suggestions
And let you know the outcome
Ralph

I fixed this problem with the rising edge valid fix. I forget now which one was wrong, but on my Ruida they both match now, and one was false and one was true in my settings. Try both ways. If I had to guess it was my Y set to false and it should have been true, but just going by memory.

Good way to check if that’s the likely issue is do a test engrave on some cardboard, and set it to fill+line. If that’s the issue the engrave will be skewed, but then the line will go back and outline properly. That pretty much should confirm a setting and not hardware problem, that’s what I had.

Thanks Aurich
Enabling PWM to rising on X and Y axis solved the problem, I had to further tweak the over scan offset to correctly line up both the scan and line output.

Regards Ralph

1 Like