I am trying to learn how to cut female moulds for fiberglass layup of foil shapes. I can model the foil in Rhino, subtract it from a block and get what looks right in Rhino and after export in PartWorks 3D - a block with a foil-shaped pocket.
My problem is that when PartWorks 3D generates the cut files, even where set to cut top only and the model set zero below the top, the finish cut file tries to dress the outer perimeter of the block, rather than just the mould pocket. (It's found a couple of screws, so far - two expensive bits gone )
Is there a way I'm missing to instruct it just to cut the pocket?

Charlie Iliff