what would be best for brazing steel?

Hi
I am new to gas welding and work in the HVAC field and have two primary needs, copper to copper brazing (easy for most any torch), but my second
requirement is a little odd:
often, we run into a home compressor (steel) that has a vibration crack where the body of the compressor and the 3/4 suction line join, this crack results in a refrigerant leak out of this compressor body crack, and the compressor is therefore doomed and replaced.
I think that a silver brazing, using something like the fancy Silvaloy A-56T would work, and save these expensive compressors, it liquefies at about 1200 F. It is said to have the lowest brazing temperature, best wetting and best flow of all the cadmium-free alloys. Its low zinc content minimizes problems due to excessive heating (as by less skilled operators, LIKE ME!)
My question is: what gas/fuel combo would be best for this application, and which brand/model of torch.
I am not sure whether to get something like the light duty Victor Medalist or Cutskill "port a torch" type $300 oxy-acet tote kits, or something like the Smith Quickbraze kit, or something else entirely.
please note that, in addition to portability, that I need concentrated heat, as I do not want to heat up the whole area way too much, lest the entire suction line fitting stub might come loose (it is welded in at the factory when they build the compressor) I also need *enough* heat to counteract the fact that the steel compressor body will act as a big heat sink when I am trying to braze, so I am afraid I will need an oxy/fuel solution, rather than air/fuel.
thanks for the help!
cowboy
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On Fri, 8 Apr 2005 08:11:19 -0400, "cowboy"

That should work. Those fittings are installed into the compressor with silver solder at the factory. I found that out after accidentally pulling one out while trying to undo the silphos joint.

Agreed except for the welding part. The ones I've run into are high temp silver soldered. Keep in mind that you'll need to really clean and flux the steel to get the silver solder to stick. Also be careful not to over heat the steel since it will not take silver solder after over heating.
Personally I'd just go with the Victor torch. They're fine for the task at hand plus they're cheaper and easier to find parts for.
Wayne Cook Shamrock, TX http://members.dslextreme.com/users/waynecook
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I have a "Little Torch" with a really cool twin-flame tip. This has a semi-circle of tubing with two tips at 180 degrees from each other, pointing at each other, allowing you to put heat completely around the tube quickly.
Check it out:http: www.littletorch.com/tips.htm
I use this "Little Torch" with one of the portable O/A setups, and it works really well for me for silver soldering stainless...

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I've done it with both torch types, and using silver (45% brazing) and flux of course. For the larger compressors, Oxy/Ace would be better as you can get it hot in a hurry and then have a wet rag to cool down after the brazed area has cooled somewhat. Just make sure the steel area on the compressor is very, very clean of paint, oil and other, also make sure you don't leave the torch tip in one area long enough to discolor (burn) the steel, otherwise you'll have a tough time. Repaint when done so the steel doesn't rust. B.G.
cowboy wrote:

primary
second
crack
crack
the
Silvaloy A-56T

about 1200

and
minimizes
ME!)
application,
Medalist
like
concentrated heat,

entire
factory
counteract
when I

rather

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