[Zeke]

steve, you better go back and read the page again. No mention of sheet metal that I could find. Go back one page and see the spade bit for sheet metal. BTW, a sheet metal bit is just sharpened at a low slope.

Methinks the brad point will give you some problems and hang up big time at punch through. How big a hole do you need? Over 3/8ths and you might want to think about a bi-metal hole saw. I don't see anything less than 5/8ths, though.

Can you back up the work or place the metal on wood? That's the ticket.