Re boric acid

Richard I find boracic acid good mix with water to a paste then
brush over any surfaces that could get to hot. Its also a great
flux sulpheric acid 1 to 6 will remove any residue. This is all
I use for flux now its also great for protecting diamonds best

If you mix the boric acid powder with alcohol instead of water,
you can burn off the alcohol and leave the boric acid on the
piece that you are soldering. I would still yse a flux at the
solder

Rick Hamilton

You know I don’t think boric acid on its own is protection
enough for silver soldering which I do an awful lot of.
Especially if you’re doing many repeated solderings, boric just
doesn’t cut it. Pripps flux which you make yourself is much
better and provides a nice coat of “glass” to keep oxygen out.
But, if you do alot of solder operations on one piece you’ll get
firescale anyway no matter what you do. Pripps keeps it down as
much as possible. Pripps is boric acid, borax and tsp. If you
need directions on how to make it let me know…Dave

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