Homebrew PCBs

Looking up where to find Tarn-X, I found out that the chemical in it
can be bought for next to nothing.

http://www.ganoksin.com/orchid/archive/200305/msg00153.htm

It isn't a polish or an etchant, it is a chemical that converts the
sulfides back to the base metal. 

"If you like this and use more than occasional amounts, though, you
might wish to go straight to the source.  The TarnX brand is just a
repackaged jar of a relatively weak solution of the chemical, with
fancy labeling and advertising budgets behind it.  The actual
manufacturer of the chemical the TarnX folks use, is another company,
Vin Rock Inc 3024 Fontenay Rd Cleveland, OH 44120-1729 Phone:  (216)
991-9593   They call it "CQ-2 silver cleaner".  They sell a pound of
the dry chemical for (ten years ago, at any rate), around ten or
fifteen dollars, and it goes a long way.  I don't have a web site URL
for them, and don't actually think they've got a web address, so
you'll have to use that old dinosour of ancient technology, the
telephone...   That pound of chemical makes up a gallon of the full
strength solution, or if you want it the way the TarnX folks package
it,  several gallons  (packaged TarnX is mixed weaker than the
manufacturers recomendations, and doesn't last all that long as a
result).   I got that tidbit on their dilution rate, from the Vin-roc
sales people when I bought the stuff by the way, and can attest that
mixed to the proper strength, it works a LOT faster.  The stuff does
have a faint sulphur smell, which some people don't quite like, but
it's not especially harmful or anything "

Steve Greenfield