Someone posted before I could finish this, but I am posting it anyway.
What's the best liquid flux for soldering copper onto stainless steel, HCl or H3PO4, of how many percent concentration each ?
How's logical explanation on solder sticking process will actually work ?
Some suggest Phosphoric acid better, actually I tried both works, ...many thanks in advance !
This forum is a learning forum.
We often give hints on how to find the answers.
One technique is to use the a search engine on the Internet.
I got some interesting results using GOOGLE using the phrase
flux liquid for soldering copper onto stainless steel
GOOGLE also suggested I might use other phrases
soldering stainless steel to copper wire
copper to stainless steel pipe connection
soft soldering copper to stainless steel
flux for soldering stainless steel to copper
I got some more results using the phrase
H3PO4 soldering flux vs HCl soldering flux
Once you have done some research and you still are unclear as to an answer, you may come back here to discuss your results.
It is good that you have experimented already.
Additionally, your question is fairly general and may need some further information such as you application.
Is it electrical?
Is it plumbing?
Is it to do with a brewing system?
This will help any member who wishes to respond.
By the way there are other factors that might influence your decision .
The corrosive effect of the flux after the soldering is long done.
If by chance you have not done so
Please read the forum rules.
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Click on the link near the top center of the forum page.
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