Wild Bill wrote:
Hi.. power tools are sometimes the first thought, but a manual method
works well too.
You're wanting to slit (to obtain a flap) rather than slot, and a
tool
that I've used on all kinds of sheet materials is a scoring blade in
a
utility knife.

Stanley and others supply these hook-shaped cutting blades. You can
cut
steel sheetmetal with these blades, and the only material removed wil
be
a fine curl of the metal. They work much better on aluminum or
plastic
sheet.

Starting with light pressure, these blades will establish a cut
that's
easy to follow with more firm pressure in subsequent cuts. Thinking
in
small increments, and numerous draws (particularly in steel) of the
blade wil get the job done nicely.

Here on Staten Island, Home Depot and Lowes have pretty much
non-existent customer service, and no one I could find in either of
their understaffed stores knew anything about a scoring knife.

If I cannot find these blades locally, can I get recommendations on
where to order the specific blades needed?

I have to score and break off something close to .0156" wide strips of
metal from sheets that are .032" thick.
Thanks a lot."

Darren Harris
Staten Island, New York.