On Sun, 22 Jan 2006 02:08:53 -0500, Brent Philion
wrote:

With the lack of an AC tig machine and an AC inverter appearing to not
be in the cards in the near future i"m looking at using Oxy/Acetylene to
do the al Welding due to the availability of an OA rig. Mainly i used it
for cuttingbut thats not to say its impractical for welding. If i
remember right OA has been used for Al welding for a long time
specifically in the aviation industry.

Compared to TIG how hard is OA welding of aluminum and are there any
special types of requirements for doing it? The only OA welding i would
be doing would be on Al and the rest of the time it would be used for
heat/cutting

I already have an OA torch (Cheap Harris style kit) but stumbled across
a real Victor 100 Handle Might i be better off getting a fresh welding
tip for the victor 100? than the giant beast of this harris one?

I will likely never weld larger than 1/4" with most work being smaller
than that (1/8" to 1/16")

the Victor 100 seems to be the most like the tig torch i'n used to
compared to the big beast of the current torch. If thats the case than
has anyone used gas quick connect fittings to swap torches and are those
reliable or am i looking to blow myself up

BLowing myself or the shop/house up is EXTREMELY LOW on my list of
priorities

O/A can definitely be used to weld aluminum. It is the first choice
of many for sheetmetal on aircraft and various automotive work. I
do it routinely with 1/16" and less, prefer TIG for thicker
materials. It would take a big tip and a lot of gas to weld 1/4"
aluminum, but it certainly can be done. 1/16" to 1/8" is easily
done with O/A. Some say that gas welds in thinner metal are more
ductile than TIG or MIG and hold up better to subsequent metalworking
operations like planishing or further forming.

I don't think welding aluminum is any harder with gas than it is with
TIG. With metal 1/16" and less I think it's easier -- but read on.

You can order a videotape on O/A welding of aluminum from
www.tinmantech.com
I've not seen it but it's probably a good start. You can also
download a short video showing aluminum being gas-welded from
www.cut-like-plasma.com It's objective is to sell the Henrob torch.
Don't worry about that. Your torch will work fine. The Henrob's
performance as a cutting torch is impressive, but others have
indicated preference for other torches for welding and the Henrob
is a rather pricey torch. Your torch, with appropriately-sized tips,
should work fine.

Special requirements: yes! Aluminum welding requires flux. The
reverse polarity part of the AC cycle cleans oxides with TIG,
flux does it with gas. Some welding stores will have it. The tin
man and cut-like-plasma offer it too.

Aluminum flux produces a bright incandescant "flare" that must be
blocked in order to see the puddle and to see when a puddle is
imminent. Eyewear that blocks that flare is absolutely essential
to successful gas welding of aluminum. Regular goggles don't do it,
not even close. It's not a matter of "dark" but one of blocking the
flare without obscuring the puddle.

Cobalt blue glass was used for many years, but is no longer used
because it doesn't block some harmful rays. There's probably some
OSHA overkill there for the occasional user, but I've used them and
can tell you that there is now a far better choice available.

The TM2000 green dydimium lens, available from the tin man,
cut-like-plasma and some other places, is a bit pricey but I'd regard
it as the single most important tool to have for gas welding aluminum.
It works extremely well. I know of no cheaper alternative that works
remotely as well.

Cut-like-plasma does offer an alternative lower cost lens.
I've not tried it. HIs video is obviously shot thru the TM2000. If
you're serious about learning to weld aluminum with gas, I would
strongly encourage you to get a TM2000 filter.

The other indispensible tool is a stainless steel "toothbrush" for
scrubbing the metal clean just before welding. They're available at
any welding store for well under $2.00 each. If you're familar with
TIG welding aluminum you know about those already.

I don't know anything about gas quick-connects. I sure wouldn't use
compressed-air quickconnects, don't even think about it! Those
either leak or are about to.