pH down is the exact same ingredient as in Sparex #2 without the
gunk used as a filler by Krohn industries. If you search the archives
use topic words, like pickle, substitutes, keep em simple, they are
however, there probably under pH down though as they are I believe
catalogued by the subject line in a post and not cross referenced by
subject area… By the way easy solder has the most zinc and shouldn’t
be used for repeated heatings, go with a hard or medium hard,at
least, for multiple heating rquirements. that way your joints won’t
be afected in the long run. Easy is used as a final operation or in
an operation in which the piece may be affected by high
temperature requirements rer
Depends on what you mean by pickle substitute. The commercially
sold pickles, such as Sparex, are sodium bisulphate.
-also another solution in a pinch is to use your ultrasonic cleaner.
I find it works great on breaking up the boric acid crust on pieces I
don’t want to put in the pickle pot. Give it a try. Safe also.
Ok Once more, Most of the jewelry I or the Dept.'s Of Archaeology
at Tulane University, University of New Orleans, and Royal College
in London found on digs was 24 karat gold based
The reason that we find jewellery in 24 karat is because all base
metals were leached out by the environment and not because it was
made this way. There are also plenty of silver surviving as well.
There are plenty of research done on this subject. Spending a 1000
years or more, buried in the soil is much harsher environment that
overnight bath in pickle. That is simply common sense.
I feel pickle left on a piece (IE the inside of a soldered hollow
form, a bead for instance) will eat at the solder. after the last
pickle I will put in a baking soda bath to neutralize acid. I put
it in a film canister in the ultrasonic if it has only a small
opening
Much more important than worrying about damaging the solder would be
that pickle left inside of a piece will eventually often find it’s
way out through minute pores or that small hole. It had to have some
way to get sucked into the piece when it was first placed in the
pickle (a strong reason to quench first in water, not in pickle, so
the “sucking” into the work that might occur on cooling sucks in only
water, not pickle.) Anyway, if it ends up finding it’s way out of
the piece after that piece is, for example, hanging around the neck
of your customer, you’re going to have one very annoyed customer
indeed. With most work, simple rinsing and the usual operations after
pickling, such as cleaning after polishing for example, are quite
enough to be sure no pickle remains. But if you’re doing hollow work
that can trap a bit of liquid, take great pains to be sure no pickle
or other liquid remains inside. Gentle heating to just over the
boiling point of water will drive out any water remaining in a piece,
but pickle, if there, just dries out to the dry acid. So be sure it’s
well cleaned out right after pickling, and better, try to keep pickle
from entering the hollow parts if you can (by quenching in water
after heating, you fill the work with enough water to mostly avoid
the problem, especially if you then expell the water with a bit of
gentle heat before proceeding with other operations.
I will run a test with pictures of how acids can destroy a solder
joint, irrespective of soldering techniques. On my ganoksin blog,
if you wish Your call.
The problem with this experiment is How can we know the quality of
soldering.
What I am saying is that well soldered joints will not be affected
by the pickle. Besides, there is an easier way to conduct an
experiment. Everybody, mix a small batch of fresh pickle. Cut a
square inch of solder like it comes from your supplier and put it in
the pickle. Keep it there for as long as you want. Let me know what
happens. I can bet donuts for dollars that it will be unaffected. If
any corrosion will be observed, change you supplier. All commercial
pickles have inhibitors to prevent reaction with precious metals.
To reiterate: if joint fails in pickle, it is the joint, but not the
pickle.
True. But you can find most of these pieces with their pearls and
stones still intact. I would have thought that if the environment
had been so destructive then a pearl or a soft emerald would
suffer much more than the metal.
Emeralds at that time were real emeralds, so been buried was not a
problem. Natural pearls are far more resilient than experience with
cultural pearls may indicate.
I will run a test with pictures of how acids can destroy a solder
joint, irrespective of soldering techniques. On my ganoksin blog,
if you wish Your call.
Hans - not a bad idea at all. I’ll see what I can come up with also
with the microscopes I have available. The caveat being that it may
take a while since my own scopes are not set up for photography and
the ones that are aren’t mine.
Cheers all,
Hans 2 (or also)
in Parrsboro Nova Scotia on the Bay of Fundy
But you have to leave you work in the pickle longer with citric
acid, so then it might be easier to forget to take it out.
For what it is worth, I have used citric acid as my pickle for the
past 3 or 4 years. I am 100% satisfied with it, and if it actually
does take longer, I do not notice it, so it can’t be that much. I buy
it on line much more cheaply than I found it locally, though I had to
buy something like 5 lbs of it, which will last quite a while. It
weas $6/lb locally, maybe a third of that by mail. I don’t remember
where I got it, but you can just google it.
Let me “ditto” what Noel said about using citric acid pickle. Yes,
buy it online for the best price. Just like other pickles, it works
faster when it is hot.
Judy in Kansas, who is having to choose between canning fresh vegees
and making stock for the next show!!
Practical effect is minimal. It leaves nice clean surface and
ensures quality of soldering.
Well, first of all, to advise newbies (who look to the pros here
for insight and will be among the audience) to boil anything in acid
is probably dangerous, if not downright irresponsible, just MHO.
Particularly so since absolutely no caveats or instructions
accompanied the recommendation. A little splatter of acid in eyes,
you may be a jeweler no longer. Unfortunately the practical effect
of bad advice is not always minimal.
But maybe I’m the only one who feels this way?
Its simple, don’t leave it in the pickle overnight. If you’re like
me and just plain forget stuff cuz you’ve got stuff coming at you all
day, post a little note to yourself at the out-the-door-for-the-night
lightswitch or alarm panel “check oxy/gas, pickle”. You might also
get into the habit of hanging your object on a hook or basket when
pickling, you can see at a glance if you’ve got something in the pot.
Paint it day glow if you have to.
Much more important than worrying about damaging the solder would
be that pickle left inside of a piece will eventually often find
it's way out through minute pores or that small hole. It had to
have some way to get sucked into the piece when it was first
placed in the pickle (a strong reason to quench first in water, not
in pickle, so the "sucking" into the work that might occur on
cooling sucks in only water, not pickle.)
Also, to make doubly sure that it doesn’t contaminate the interior
space, I fill a hypodermic needle With baking soda and water and
inject the piece, then inject it again (several times) with plain
water until I’m sure it is “clean” inside. The dry it with a hair
dryer and I’ve never had a problem. And yes, I do quench in water
first (learned that in the first basic class I ever took).
And what about the fumes? (remember, we're likely talking to
students here, without a really well equipped ventillation
system...)
That is a good point. I should have mentioned about safety.
Boiling sulfuric acid is dangerous. If one inhales micro-droplets,
creating by boiling, it causes lung paralysis.
That said, I am using unlined copper pan for this procedure. It is
important for it to be pure copper. The acid will completely react
with copper before reaching boiling point and vapors emitted during
process is just water. What is left in the pan is simply water
solution of copper sulfate also knows as “blue vitriol”, which can
be disposed without any problems. However, use of any other vessel
than pure unlined copper is dangerous.
If one has never been shown technique in practice, find a goldsmith
who is willing to demonstrate the process before using it.
By real emeralds I assume you mean natural, non oiled? Oil over time
would leach out.
While soils can leach out base metals over time, even thousands of
years wouldn’t be enough to actually purify the piece much below the
surface. Otherwise all those million plus year old nuggets would be
999 fine.
For what it is worth, I have used citric acid as my pickle for the
past 3 or 4 years. I am 100% satisfied with it...
I’ll second that. I got tired of breathing Sparex fumes,
particularly when someone had left a pickle on overnight. We are
much happier with citric acid. I do keep a jar of Sparex in the
cupboard as heavy artilery just in case, but find we use it to
disolve hard to remove broken drills more than anything else.
What is left in the pan is simply water solution of copper sulfate
also knows as "blue vitriol", which can be disposed without any
problems.
Mostly, yes. But it should be noted that copper sulphate can be
toxic to fish, as well as to a number of aquatic plants/algae, etc…
That means that in some cases, it should not be just dumped down the
drain in any but minute quantities. Check with local waste water
authorities for guidance. Most people won’t have to worry about this,
but there are some locations where environmental concerns limit the
degree to which metal salts like copper sulphate can just go down
the drain. And of course, as always, context is important in such
discussions. For those who may not be fully aware of the procedure
Leonid is describing (which frankly, I’d forgotton. it’s been years
since I did this, but he’s right, it’s useful in some situations.)
the quantity of sulphric acid pickle invovled here is quite small. In
tool supply catalogs, the older ones or from companies still
carrying the older traditional tools, one often can find these small
copper pickling pots. Intended, from the look of it (and the way I,
at least, was shown) to be simply held (put a handle on it) or
supported over a bunson burner or similar heat source (we used to use
a lab tripod stand). Those little copper pots would hold maybe a
quarter cup of liquid, at most, enough for one or two rings at a
time.
Leonid, am I describing roughly the same procedure you are here?
By real emeralds I assume you mean natural, non oiled? Oil over
time would leach out.
Actually emerald oiling is the very old tradition. It is even
mentioned by Pliny the Elder. The problem with contemporary emeralds
is that they mined by using explosives. The only way to keep them
together is with epoxy. I am afraid but most of the emeralds on the
market would fall into this category.
You right about surface layer, but comment was made in relation to
solder joints. Jewellery found in excavation have solder joints
composed almost of pure metal. The reason for this is leaching of base
metals our of the joint. Nevertheless, the joint still stays together.
This is a testament of soldering skills of our ancestors.
Its simple, don't leave it in the pickle overnight. If you're like
me and just plain forget stuff cuz you've got stuff coming at you
all day, post a little note to yourself at the
out-the-door-for-the-night lightswitch or alarm panel "check
oxy/gas, pickle". You might also get into the habit of hanging your
object on a hook or basket when pickling, you can see at a glance
if you've got something in the pot. Paint it day glow if you have
to.
I’ll 2nd Neil’s suggestion.
Early on, I sometimes forgot to turn the pickle pot off when
quitting time came around. The result would be a dry pickle encrusted
pickle pot in the morning.
My solution was to turn on the light in the closet the pickle pot
was in when I turned the pickle pot on. I’ve not forgot to turn the
pot off when leaving for the day/night since.
This approach could also be applied to other items as well.
Jewellery found in excavation have solder joints composed almost of
pure metal. The reason for this is leaching of base metals our of
the joint.
The other reason, at least in the case of pieces from antiquity, is
that they weren’t actually solder in the sense of an added solder
alloy being flowed into the joint the way we do now. Rather, most
work was done by processes we now refer to as “granulation”
technique. In an age where soldering/joining was done mainly by
putting work into a kiln or over a “hearth” to join, rather than
with a torch, a method where the alloy needed to make the join is
already in place, rather than needing to flow into a joint, had
advantages, and as well, avoided the need to know how to formulate
more complex solder alloys. This type of joining tends to use less
“solder” in the joint, as as the work remains heated longer, the
eutectic or other lower melting alloy that forms in the joint areas
melts/fuses, but then with continued heating, the componants of it
that allowed the lower melting would simply diffuse further into the
parent metal. I’d bet that by the time most such work was removed
from the fire, the joint would have already solidified from diffusion
of the alloying componants, and even when made, there would not be
all that much “solder” or alloy to detect. As well, although the
diffusion of copper or other base metal into the parent metal is
much faster while the joint is being heated, it continues at a slow
rate even when cold. So over time, even if base metals are not
chemically leached out of the metal by being buried etc, the amount
of base metal concentrated in the joints would still become greatly
diminished. Combine that with the leaching over time that you
mention, and the result would be considerable difficulty in finding
any difference in the joint composition. Whether the leaching over
time, or simply the mechanics of how the joints were done, or
diffusion into the parent metal over time, is the major reason for
this, would be difficult to tell for sure, since the end result is
the same.