ORIGINAL: Ram Jet

I think qldViking has it. I do remember a wierd woodworking tool with a round bit that runs through the center of a square cutter with sharpened end like Viking suggested but I can't remember where I saw them. They would certainly be more expensive than viking's idea. I have a set of "cork borers" used in scientific labs for, what else, boreing holes in cork stoppers. Very handy too for punching holes in balsa, thin plywood etc. You can make your own out of brass or stainless tubing.

Bill