"Larry Jaques" wrote in message
...
On Wed, 18 Jan 2017 11:47:01 -0500, "Jim Wilkins"
wrote:
................
http://www.eastwood.com/eastwood-air-shears.html
Is 18ga a casually suggested or actual maximum for sheet thickness?
Salesmen usually oversell specs.
The 22 gauge pool column steel was difficult to cut with a hand model,
more from slipping out than the cutting force. I don't remember how I
cut the approximately 18 gauge stainless for the bucket of my loader,
maybe the 8" Enco shear? I don't have any mild steel in that
thickness. A 24TPI blade in the 4" x 6" bandsaw cuts thicker sheet
metal well enough.
The companies I built equipment for chose 0.062" and 0.093" 6061
aluminum for electronic enclosures. I bought 0.050" 5052 for my hobby
work because 0.062" strains the 3-in-1, and most recently used
unlabelled 0.031 to fold a box. It cuts and bends like 6061 rather
than the flimsy aluminum in a Bud chassis, which had mistakenly
convinced me that 0.031 was too thin. The only minor problem is that
my stock of PEM nuts was salvaged from 0.062" scrap and they protrude
slightly through the 0.031". The flange can be bent back a little to
make the visible edges close flush.
The body men where I used to work used air chisels and either
electric
or air shears like the above. The chisel bits worked well on thin
sheet like fenders and 1/4 panels. Hover over the 3rd one down:
http://tinyurl.com/h3xmoun
I've used one to cut patch material from a scrap fender, so I wouldn't
have to shape the wheelwell flare from a flat sheet. I think it's
overly aggressive to cut out a small rust area near an edge.
Have you seen or used the Beverly style throatless air shears from
HF?
I just saw them online. http://tinyurl.com/hpejdn8
I've used a bench mounted Beverly shear at work. IIRC it distorted the
metal a little too much for flat control panels someone else paid me
to make but would have been fine for auto body repair. A warped
control panel can break meter bezels and pull out molded-in mounting
screws.
I always tried to make my sheet metal work look as professional as my
soldering. The Enco 8" bench shear leaves one side straight.
The steel of the uprights and top rail from the pool is a good
balance
between stiffness and workability and the coating stands up pretty
well to a planishing hammer. The wall is thinner and easier to bend
with hand tools.
Was that the skirting and frame for a pool, or the actual pool?
It was an above ground pool that bulged from freezing after the winter
air bags deflated. I sheared the wall into manageable sections that
now protect my woodsheds from brush/leaf fires. The thicker columns
and top rail sections are slowly disappearing into projects like
splash guards around the bottoms of the sheds and a closable box I can
neatly scoop the woodstove fire into to carry it outside and separate
the ash buildup from the hot charcoal without having to let the fire
die down as far. Shoveling the hot coals into a pail releases too much
ash and smoke. The custom box fits the door opening closely enough
that the draft draws the ash back in.
I bent the 2" wide decorative strips of wall metal that faced the
columns into U channels to rim 2' x 4' fireproof ceiling tiles to make
a generator sound dampening enclosure. Their unprotected edges shred
easily, otherwise they make good high temperature insulation with some
structural strength. A propane torch flame merely darkens the surface.
The wall metal is thin enough to bend by clamping between wood planks
and hammering down on a block that spreads the force and tightens the
fold.
-jsw