Still trying to get my head around this. I read the example rcnewcomb linked to above but how do I not get the ball nose to NOT cut the zero plane? I'm sure it is simple but I'm missing a step here somewhere. I tried letting the software insert the zero plane and gave the dish a vector outline but still get the tool marks. I tried creating a rectangle the same size of my work piece and give it a flat shape with 0 height but the tool wants to carve this along with the dish and clip art in the dish.