I get an "Over Burn" at the edges of lettering and images

LightBurn Software Questions
1

Why m I getting an over burn at the return of a Bi-directional function?

Screen Shot 2026-02-04 at 10.59.03 AM
Screen Shot 2026-02-04 at 10.59.03 AM627Ă—645 45.4 KB

Screen Shot 2026-02-04 at 10.58.40 AM
Screen Shot 2026-02-04 at 10.58.40 AM625Ă—533 43 KB

2

Probably because the machine cannot reach the 8000 mm/min speed in the 3.33 mm distance allowed by the 2.5% overscan.

The doc goes into more detail:

The RepRap calculator suggests the machine must accelerate at 3000 mm/s² to (barely) reach that speed in that distance. You can check the acceleration setting in LightBurn’s Machine Settings, although many of those settings seem aspirational at best.

3

Could be but I did tuen everything down according to my “engrave test on the sam material.

4

A picture will help us see what you’re seeing and uploading the lbrn2 file will let us check your settings.

5

I appreciate the response but I figured it out with a friend of mine who owns a laser business. I had the overscan % to short which didn’t allow for the laser to cool off or shut down before it’s next fill path.

IMG_5839
IMG_58391920Ă—2560 1.41 MB

6

Exactly:

Making the overscan region larger gets the laser head up to speed before reaching the image and lets it slow down beyond the image.

7

This only works with scanning operations, not vectors.

There appears to be some kind of mechanical issue for the scroll to look like it does. Especially with a scan operation.

image
image480Ă—386 77 KB

:grinning_cat:

8

It looks like a cut through the wood around the (2.5% overscanned) scroll, but without the lbrn2 file it’s hard to tell whether it’s an artistic flourish or good old backlash.