LB not cutting inner shapes first

I’m attempting to cut out several complex shapes that have notches and bolt holes within them, but LB isn’t cutting out the bolt holes first. I think this is because it is having trouble determining which shapes are “inside.” The file I am using is here:

Here are the settings that used to work with files like this one on the previous version of LB:
In the following photo you can see that LB is cutting the bolt hole after cutting the larger piece it is inside of:

I added a .5mm kerf to the cut to try to visualize what was going wrong and this was the result:

The kerf should have made the bolt holes smaller because they are inside, but some of them are actually larger. This shows that LB is confused about which cuts are considered inside.

I’ve tried multiple permutations of grouping and ungrouping the shapes as well as changing the cut optimization settings, but nothing has worked.

I’m using a k40 with a cohesion 3d board running Smoothie, but I don’t think that is relevant because I can see the problem in the LB cut preview before I even connect to my laser.

I found a solution, but it isn’t ideal. The way that I created these files is by exporting sketches from Fusion 360 as DXFs and then grouping each piece and its bolt holes within Illustrator. The paths that make up the organic shapes aren’t automatically joined in the DXF. By joining the path in Illustrator instead of just grouping everything, I was able to get LB to cut everything in the proper order. I have hundreds of pieces to cut though, and manually joining the path for every one would take too long. I’m hoping that there’s an easier solution, especially since this didn’t seem to be a problem in earlier versions of LB.

After importing to LightBurn, ungroup the file, then use Alt-J (or Edit > Auto-Join selected shapes). That should resolve it unless the endpoints of the shapes don’t match up. You can also set an auto-join tolerance in the settings for DXF import. I usually use a very small value, like 0.01mm.

Thanks! I only had to change a single step in my workflow. Now I save as .DXF from illustrator before importing to LB instead of .ai.

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