Impressed with your persistence! I’m also interested in whether this
would work well to join sheets or sheet and wire. I took a look at
the wikipedia article on “Verdegris.” It states:
“Verdigris is a variable chemical mixture of compounds, complexes and
water. The primary components are copper salts of acetate, carbonate,
chloride, formate, hydroxide and sulfate. The secondary components
are other metallic salts, acids (organic and mineral), atmospheric
gases and water. All the components are in an ever-changing and
extremely sophisticated electrochemical reaction equilibrium that is
dependent on the ambient environment.”
So, like most common reactions, it produces a witches brew of stuff.
The exact composition of one batch of verdegris is probably not
reproducible and probably doesn’t matter that much for most
applications, but who knows for sure? The article also details old
methods of making verdegris, evidently for paint pigments.
An 18th cent. method involved putting copper plates into clay pots
filled with “distilled wine,” which would have been high alcohol
wine, 30-65% alcohol. There would have been iron in the clay pots,
possibly leached out by the alcohol, so I wouldn’t worry too much
about the purity of the reaction.
I think you could try immersing copper strips in vinegar (5% acetic
acid) or get some glacial acetic and dilute it to 15% [always add
acid to water, not the other way round]. Or try immersing the copper
in some high alcohol solution.
You can get various forms of denatured alcohol or use vodka or
brandy, which is actually distilled wine. You can warm the solution
to get a faster reaction or even file the copper to get copper
Since there are lots of compounds here, as per the Wiki quote, I
would put this somewhere outside, such as on a sheltered porch,
while it works and would solder with good ventilation, as there may
be small amounts of some stuff you don’t want to breath a lot of. The
chemical used to denature the alcohol would also be an issue, but
probably not a major one. You’d just have to look at all the MSDS’s
for all the compounds and make a reasonable decision. Since the main
component of the verdegris seems to be copper acetate and since you
would use small amounts of the verdegris and use some ventilation
when using it, your exposure to anything would be small. Certainly
there are various copper and other metallic salts, formates, etc.
all around us.
Although most of this stuff is something you could find in an
ordinary kitchen, use common sense and eye protection as needed.
If you go further with this is would be interesting to hear of your