I am cutting a whole into a block using a cylinder and boolean difference modifier, exactly at the edge of a block. This cuts 50% of the cylinder from the block.
The problem with cutting a whole right at the edge is that it leaves empty faces in the cutout. If I move the cylinder by a fraction away from the edge (either direction), the coutout will close the faces.
This does not seem to happen with a cube, although the 3D preview looks a bit confusing.
Is this expected or a bug? Is there a way to cut a cylinder while keeping the face closed? Or is it actually closed and just looks open? I tried the "Solidify" modifier but that doesn't seem right to do for such a simple operation.
Blender version 2.9 here.