I cannot find a way to split the attached - part of a large jewellery object. I need to cut the frame with the intersecting plane to make the opening. The surface is “pierced” to take inlays. I need to keep the section that retains the inlays in the file as uploaded. When I try to cut or trim (even tried boolean) either the whole frame or the bit I want disappears. I could rebuild the surface (it is simple enough, basically just part of a simple torus) but it woud be a pain to have to “re-pierce” it - difficult to get the patterns to line up again!
My guess is this is what is messing up the meshing that displays the object in shaded views - I am not sure why it does this only after splitting, however, I’ll poke some more.
Yeah… I cleaned up the trim curves on the top half (moved that sharp point shown above away from the curve that it hits right there in the original - 3 or 4 locations -
on the top half, retrimmed and then joined it back up - the top half renders correctly.