Years ago, I bought a pack of brazing rod with 15% silver content.
Used that to join refrigeration tubing. Turns out that Mapp gas
torches work well with the 15% silver braze.

My old boss introduced me to Sta-Brite silver bearing solder. Much
lower flow temp, but doesn't seal voids as well as stick braze. If
it's old copper, or of there is a bit of gap. I use the stick braze.

The Johnstone catalog says the 15% silver has about the same melting
temps as the 1 to 2%. I don't know if I believe that. I used to braze
with mapp gas and the 15% stuff. But, tonight I just couldn't get the
map gas flame to heat the fitting hot enough.

Has anyone tried both, and is there a real difference? I'm tempted to
go buy a pack of the 15% stuff, save me having to haul out my
acetylene torch. It's easy enough to carry a 16 ounce tank of Mapp in
my tool box. On the other hand, I braze about twice a year, and for
that once or twice I can use acetylene. When I did get the acetylene
torch out, it did a nice job.

--
Christopher A. Young
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