Holy Rear Apron Batman!

[SuperRSi]

Go take a look at Mittlerbros.com and look at "sheetmetal tools" for the punches and flares. They come in all sizes. These tools use a drilled pilot hole and then punch a large hole and flare the edges. As you will see they are not cheap, but I have seen the hole they make and it is very nice. There also is a set of hole punches (no flare) from Greenlee that you can find at some plumbing or electrical supply houses. Good luck.

Thanks,

Randy