"Steve" wrote in message
...
I have about 250 sheets of used (in good condition) 26 gage roofing
material. They are all 16ft long and I will need to cut many to other
lengths while adding a shop extention.

I have tried tin snips and these cause distortion of the ridges and
spreading of the ridge pattern, hence sheet width. Not much, but enough
that I get a "fan-out" effect in the width. Also unable to fit tightly to
the next upper sheets.

I also tried cutting with an hand operated electric sheer as well and got
similar results.

Abrasive cut-off leaves a burr on the edges and I can to a lot using a
hand grinder. Recipricating saw produces similar results.

I'm told the "pros" use a sheer with a die that matches the corrigations.
The best I could afford would be a treddle opportated squaring sheer and
with our a die, I would get poor results due to flattening by the sheer
blade.

Are there any other methods that I should try.? Perhaps a saw blade for my
skil saw??

The shops that form up the sheets from continuous roll stock use a flat
shear, and cut to length just before forming.

The shops that custom cut from pre-formed stock use a shear with a profile
matching the corregations. That's why those shops will never angle-cut a
sheet for you, whereas the fab shops can.

Most of the galvanized roofing suppliers will void the rust-out warrantee if
you use a saw to cut the sheets -- although most of the barn builders around
here to just that, with a diamond blade. The suppliers say that only a
"wiping" cut that tends to smear the galvanizing and pinch it shut at the
edge will preserve the rust resistance of the sheets. They'll cancel your
warrantee in a New York minute if they see a sheet that's been sawn.

LLoyd