Thanks AB.... but how the heck does that work....??? do you drill a hole big enough to accommodate the nibbler end that does the cutting ?? and then poke it though ?? starting from the centre and working out to your circle...would that be correct ?? which in itself it looks like a reasonably large hole is required.Is that nibbler power operated or air ?? sorry for all the Q marks but I need to get this in my head that its not hard to do..........now off to mull over this with a have one on me you deserve it...awesome site