Aviation snips are great for cutting sheet metal, and I would add a
plug for those made by Wiss. They cost about four times as much as
the made-in-China snips which look almost exactly like them, but they
work 20 times better! I have no relation to Cooper Industries (which
I think still makes Wiss), but when the wire spring inside my snips
broke (after at least 15 years of use), I telephoned Cooper Industries
to see where I could get a replacement spring, and they very kindly
just sent me two.
If you ask around, you might be able to get aviation snips with
plain, rather than serrated, blades, since the serration marks need to
be filed off eventually (although I have discovered that
tumble-polishing in an abrasive media will also remove serrations and
other rough edges). HTH
Judy Bjorkman