silver solder

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golfpin

silver solder

Post by golfpin »

A very good day to all,
a little advice, guidance please, I have been given a copper/ brass fondue "Pot" to repair, it is leaking. I am a competent welder gas tig mig and a few of the older ones, here is my problem. This artifact is very old comes out of old Europe and I believe is quite valuable. How can I determine what it has been "joined" with, without it falling apart? Could it be silver solder 20% grade. Lower fusing temp?
I don,t think it is tinman,s or plumber solder but I don,t want to put heat on it unless I am reasonably sure what I am dealing with. When was silver solder first used?
To describe it, it is a fondue pot that takes hot embers in the top and the bottom while the bowl is sweated/soldered to the flue. Here is were the problem started I think someone used perhaps charcoal, too much heat, and then the "solder" melted and the pot, the "moat" that surrounds the flue in which the fondue sauce is, started to leak at the flanged juncture of flue and moat, point of solder. Am afraid am hopeless at taking pics and then loading them on to the site obviously this would clarify a lot. Would like to effect a repair at the leak rather than dissasmble the whole thing I think it would be a can of worms, no copper smiths left I,m afraid. Any thoughts or views would be appreciated.
Thanks Golfpin
hammermill
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Joined: Sun Jun 27, 2010 10:43 pm
Location: pendleton or

Re: silver solder

Post by hammermill »

if it is soft solder it will have a low melting temperature. but if it is in contact with the food area then it is really unsafe to use. also if it got hot enough to melt the solder the internal part of the joint is now contaminated and short of a complete disassemble, clean, clean again flux and re solder I doubt you will ever get it sealed.
here is a good overview

http://en.wikipedia.org/wiki/Solder
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steamin10
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Joined: Sun Jun 08, 2003 11:52 pm
Location: NW Indiana. Close to Lake Michigan S. tip

Re: silver solder

Post by steamin10 »

I do not know antiquities, but anything of the 20th Century would be most likely lead free. Cooking around lead, particularly with any acids, (cheeses, tomato sauces) will leach lead into the food. So regardless of what it was, a Tin based solder with perhaps a low Silver content, would be the answer. Given that raw silver would be high heat, Tin would provide a much lower heat level, in varying degrees. Each higher silver level raises the melt point so that by using different mixes (%) several diferent assemblies can be joined with confidence, without de-soldering a previous assembly. It is only heat control.

Please chime in if you have greater practical knowledge than mine.

EDIT: HA, hammer beat me. :D
Big Dave, former Millwright, Electrician, Environmental conditioning, and back yard Fixxit guy. Now retired, persuing boats, trains, and broken relics.
We have enough youth, how about a fountain of Smart. My computer beat me at chess, but not kickboxing
It is not getting caught in the rain, its learning to dance in it. People saying good morning, should have to prove it.
golfpin

Re: silver solder

Post by golfpin »

To all who replied my thanks ,.........took a bit of a calculated chance and heated the problem area with soft ox act flame and reran the existing solder seems ok customer happy... :D thanks again Golfpin
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