Thanks, Jim, for your informative post on Borax and boric acid
firecoats and fluxes. I had always wondered about the chemistry
Your explanation makes me think of another question, though.
I routinely use the boric acid/alcohol firecoat on silver. Does it
have any use when working with copper or brass? I’ve been doing it
anyway, but can’t see that it makes much difference. It seems to
burn off pretty quickly. (I was hoping to avoid having to use the
hydrogen peroxide pickle on every last little brass piece to get rid
of the copper coating: it always seems to etch the surface too much,
then I have to sand again, etc., etc…Makes roller printing brass
seem pretty pointless.)
Another thing, of the petty annoyance variety: the alcohol in the
jar always evaporates too quickly. What are you all keeping this in?
A jelly jar with a rubber gasket is obviously not doing the job. I
wanted something with a wide mouth for dipping. The boric acid is
always a crust in the bottom, even when there is enough alcohol
left. It’s a bore to be always chopping it up and trying to make it
a solution again. Or am I just lazy?