Hi Supagoat, it's a little hard for me to figure out which one is the boolean problem. Is one you marked with the arrow is the one that you're having trouble with the slicer?

What mesh settings are you using for the STL export?

I don't see anything wrong with the geometry in that arrow-marked one, but the issue may be that your slicer does not like to have very thin areas in it, like this spot here may be thin enough that it is deciding that the polygons there are close enough that it considers that they are touching each other:



Does the slicer have any tolerance values you can adjust?

If it doesn't like such thin sharp shapes you might need to have a pretty small chopped off flat piece at the end rather than a razor sharp point like that.

- Michael