I want to make a casing for a half circle window. I can make the casing with the two rail sweep with no problem. The problem is even if I cut out the casing first with a straight bit, and remove all of the cut off scrap, Aspire still wants to makes cut for the entire piece of wood stock even though it has been removed. Is there some way to work around this so all movement is cutting the casing instead of cutting air most of the time? Hope I made myself clear. Thanks