I know that nobody has really brought this topic up but given the
discussions of cats in the studio and all I thought it might be worth
Citrus pickle: cheap; reasonably safe; very effective; easy to use;
easy to find; even better than Sparex for some things; less harsh
than Sparex on your hands, clothes, tools, bench, etc.
I've been using citrus acid pickle for a couple months now and I'm
really impressed. Given that it's basically a food product you'd
think it wouldn't really do the job but it does. Sure, it's slower
than Sparex but we're talking a three or four minute soak instead of
two minutes, or whatever. I've adapted by having two projects on the
go at once so while one soaks in the pickle I'm designing or
polishing or whatever on the second.
I got my citrus acid powder at an East Indian supermarket for about
$10 a pound. I'm told you can get it cheaper at brew houses and other
convenient places (see Orchid post
I'm using a mix ratio of 40 ml of citrus acid powder to 400 ml
distilled water warmed to just below boiling on a hot plate in a $6
Pyrex oven dish that came with a Pyrex lid. I've marked the dish to
indicate the proper water level since an amount of water does steam
off. I top off the dish with distilled water to the fill line at the
beginning of each work day.
"Better than Sparex"? I can hear the skepticism crackling in the air
as I type this but I'd swear that the citrus works better for things
like depletion guilding on Sterling than Sparex does. My Sparex always
seemed to start taking really long after the second or third
pickling. Maybe Sparex is going deeper or something. My observation is
that on the second or third round in the citrus your Sterling is
almost powder white and burnishes up to a super gloss very quickly
after a gentle scrubbing with a mild abrasive (eg. baking soda).
Of course citrus has the well known advantages of being ferrous metal
safe (binding wire and tongs can be used in and around it without
unpleasant side-effects) and not eating holes in things.
Another advantage --gut feeling not scientific observation- is that
the citrus pickle seems to last a LONG time, as if it had a much
longer life cycle while in use or something. Also seems to have a
longer shelf life while in solution, not that that really matters to
most of you.
One downside that I can think of is that you must heat the citrus
solution in order to get reasonable pickling times. Cold citrus
pickle works at glacial speeds. Actually I suspect that it's neutrinos
that get rid of the firescale when it's sitting in the cold citrus
pickle but I don't have that kind of instrumentation in my studio.
Those of you who've seen my ramblings for a while now know that I
was, not so long ago, extolling the virtues of hydrochloric acid
(HCl) as a pickle. I still use in on occasion for really stubborn
firescaling --just a dip between rounds in the citrus, rinse between
pickles-- but given the nasty vapours, rust-fogged tools, and low
penetrating power due to insoluble salts on the surface of the
workpiece I went looking for alternatives and thus discovered the
citrus acid. One moves on as necessity and providence dictate.
I suppose I should mention that I use Sterling and base metals only,
no gold these days.
Usual disclaimer: I am not now nor have I ever been a seller or known
to a seller or manufacturer or known thereto of citrus acid powder. I
do however like citrus fruit and strongly encourage their judicious
consumption. Apples are nice too. Bananas are okay once in a while.
Passion fruit were thusly named by a cruel and very cynical person.