what your missing is a boundary curve, imagine you have a 12" cube, 1 cubic foot of metal, the top is Z zero. you want to stay inside, make a line, rectangle, 2 endpoints, and draw this just inside your cube, at z zero, now when using z rough, or most other paths, check the boundary curve, when you are selecting your elements to machine, it will ask you to select your boundary curve (box, circle,whatever) now, surfcam will ignore the outside of your mold |