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View Full Version : SnAg solder (Stay-Brite): which fluxes are suitable?



DaBit
02-09-2002, 04:24 PM
I have big trouble obtaining an oxy-acetylene torch to do the brazing job. Also, flowing nitrogen or argon through the piping is a problem, and without inert gas flowing through the piping during brazing a lot of copper oxide scale is formed.

The answer: tin-silver solder. It is suitable for HFC refrigerants, suitable for iron-copper joints, and it's melting temperature is within reach of a normal butane/propane torch.

The Americans over here probably know it better as Stay-Brite. Stay-Brite is a 96%/4% tin/silver allow. Here in The Netherlands Stay-Brite is not sold, but 95%/5% tin/silver solder is easy obtainable.

The big disadvantage of SnAg solder is the acidic flux used normally. I can imagine that even slight amounts of acidic flux in the refrigerant piping is not exactly healthy for the system. By applying the flux very carefully this can be reduced to a minimum, but I doubt it can be eliminated.

What kind of fluxes could I use for copper-copper joints and copper-iron joints? It helps me if I know what the active ingredient of the flux is, since American brand names do not make it to Holland.

Can anyone over here give me some advice on how to work with SnAg solder on refrigerant piping? Of course, I am comfortable with the pipe cleaning and soldering process itself. I only need to know where the specific pitfalls are.

CuGe
14-08-2005, 06:44 AM
Your best bet is to get the correct material and equipment for the job. I am sure that it is readily available in Holland.

chillin out
14-08-2005, 05:08 PM
Hi Cuge,

That was posted 3 years ago, and Dabit hasn`t been on this site for 6 months.:) :)

CuGe
14-08-2005, 08:29 PM
whoops, was up late last night and getting into it...no excuse really