{snip}

Even airplane builders call 'em tin snips. One thing others haven't
suggested, that I would, is to cut about 3/16" short of the finished
line, then a second cut on the line. The snips tend to curl and distort
the metal. The thin strip will curl easily, which will leave the good
section undistorted.

Yea, you are right; but I went with the name used for the tool on the
internet. Tin snips searches on the internet were just a large scissors
type of metal cutter with no mechanical leverage. Like the old fashioned
metal cutters about 18 inches long. I wanted to make life for the OP easier
if he was to do a search at Amazon.com or Sears tools.

Phil