Version 3.0 trying to Preview I get the error above. This model generates linuxcnc gcode in Version 2.8 but has some bad paths the cut through part. I verified manifold in Blender using the 3D print addon. This forum won’t allow me to attach an stl file.
This is a hydrofoil wing that is almost 1 meter across on a giant 52x52inch cnc router table.