Plasma cutter. Milling machine. Oxy/Acetylene torch.

Yeah. I was thinking maybe the O/A torch might be about all there is for that trick.

I have used my Dremel tool with a carbide bit to do something similar and it worked fine.

I have the metal eating burrs. Do carbide tips work much better than the burs??

Plasma cutter is something you need to see in operation. It makes an O/A torch look like a brace and bit compared to a modern electric drill.

I have never tried a metal cutting burr so cannot compare them. The carbide bit really cut fast and deep.

If you use it, wear glasses and a long sleeved shirt or sweatshirt. It throws small pieces of metal.

My arms looked like I had been shot with a shotgun. Not too deep but lots of tiny cuts. None hit my glasses that I know of but I would not use that bit without eye protection.

great info. Thanks

For a more refined hole you could use a unibit or stepped bit. They go up to about 1" in size and do a great job on plate steel.