I have one regular and one heavy-duty "flying parts" or whatever they are called hole cutters. The heavy duty is too big to cut a 40 mm hole. The small one probably won't cut 1/4"+ thick 6061 aluminum. I'd rather try something like this...Can you tell what sort of shank it has? I doubt square will work. Round might work. I would prefer hex.
Any suggestions for a 40 mm aluminum hole saw, to be stuck in a drill press?