I’ve been working with copper for decades now. I break just about
every rule we are supposed to do when working with metal. Things that
I’ve accidentally (serendipity) come across in all those years. One
is the problem of copper solder.
The best and cheapest I’ve found is the stuff Rio sells. The copper
bearing solder. Yes it is grey in color, BUT!!! you can do
little tricks to deal with this. First I DO NOT CONTAMINATE MY
PICKLE! If by chance I slip up and solder something else like brass
or nickel, I don’t want it to plate with copper. My silver and gold
go into a different pickle pot. But I do charge the pickle with a
little copper first.
What you need to do is get a good bi sulfate pickle compound. I buy
Rio pickle by the 5 gallon tub. Next anneal a bunch of copper. put it
just like you would normally do, into the pickle pot and you have
enough copper now to do what you need to do.
Second, now you solder normally. When you put you piece in the hot
pickle, just leave it about 30 seconds, a minute at most. The solder
will remain copper colored. But like the other poster said I do use
higher heat with my work. I also use a hot just before boiling pickle
I also found if you need to do multiple solder joints, which can’t
be done at one pass, I tend to not pickle in between. I know everyone
here is going to get their panties in a twist over that one. It
happened late one night when I was trying hard to get a piece done,
when out of desperation and lack of sleep I forgot to pickle and I
soldered the piece just fine.
The black crap didn’t affect the solder joint. Maybe it is the
copper bearing solder doesn’t need flux, and will flow every where if
you are not careful. It works for me and I’m not going to argue with
blind dumb luck when it happens.
Aggie, blind, dumb and lucky