I’m just a beginner and I hope that some may find this more amusing
I’m using brass rod (1/8" and 3/32" in diameter) and Stay-bright
soft solder. The work is a rolling ball sculpture in brass and wood.
All the brass parts fit together with no gaps, I get them
mechanically clean, flux 'em up and the butane micro torch does a
fine job of flowing the solder along the joint. The joints need
pliers to come apart.
After soldering, the track goes into a sodium bisulphate (aka Sparex
2) solution (1 lb sodium bi to 1 gal H20). The solution is unheated
and I thought it safe to leave overnight. When I lifted the track
the next day it just fell apart. The solder turned into a black
powder. Nice looking brass though.
The Stay-bright is a 96/4 tin/silver solder. I assume that the
pickle is dissolving the tin from the very small amounts of solder.
I guess that tin dissolves faster that the brass (zinc and copper).
Is this typical? I’m not even sure I need a pickle, just elbow
grease. But I do want bright shinny brass.
Should I switch to citric acid?
Eventually I’ll have brass track around four feet long, so I’m stuck
with long pickle times.