Good evening everybody,

   I have been getting a weird error from two equal parts. These two sections cant have ribs cut out for some reason.
This is a 3d printed assembly for a low-cost arduino plane.

The mirrored segments on the other side did fine.

Could someone please give a method to solving this?

I extruded the cutouts because other forums say that it might be a type of zero thickness problem.

The actual plane itself.