RE: cuttin a hole in a foam wing
I clamp a wing tube at the desired location, then I place the cores in line with it where I want to cut the hole. I use a socket that is sharpened at one end and feed it into the core while turning. You will get about an inch to an inchand a half deep before a cylindrical plug will break off, and needs to be cleared. The core should be ''regestered'' to the jig so you can remove it to clear the foam plug from the socket, then replace it in the exact same spot. I clamp rails at the trailing edge and tip for this.