Lightburn QR code producing individual squares

Using a Galvo laser when I engrave a Lightburn QR code I get individual squares. This is not a problem for a phone to read but very hard all our 2D scanners. I’m just not sure what settings to adjust to get a more complete fill.
Any advice would be great!

2023-01-24 10_03_34-Cut Settings Editor - LightBurn 1.3.01

I note you have ‘Flood Fill’ enabled (green). Turn that Off (red) and then another test run, and share those results if you will. :slight_smile:

That did it! Funny, based on the name of that switch, I would’ve expected the exact opposite to happen.

Fair, naming a ‘thing’, for maximum understanding and ease of recognition, can present challenges. :slight_smile:

To assistance, we provide additional information for most things within LightBurn by hovering for a tool-tip for that thing. In addition, while hovering over that thing - Hit F1 to be taken to that section of our documentation, where you should find even more helpful information about that thing. Not every ‘thing’ just yet, but we have been adding these connections in hopes folks find them value in learning and enhancements to their workflows.

Flood Fill

Flood fill tries to eliminate travel moves across blank space, so it’s perfect for engraving something like a large, empty rectangle, where the blank area in the middle would consume most of the time spent.


  • This option is incredibly useful when you need it, but is very sensitive to machine tuning and backlash, and can end up leaving gaps in your engraving if the design is complex and/or your machine is not set up optimally.

If used on complex designs, Flood Fill can produce engraving paths that jump around a lot, and return later to fill in missed spots, which is why it can leave gaps if the machine isn’t well tuned. Use it sparingly, and use the Preview tool to see how the option will engrave your design so you aren’t surprised by the path it takes.

Thank you!

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