I just found out that GIA is offering Precious Metal Clay classes in Tucson
at the “big shows” for $295. If interested call them at 1-800-421-7250, Ext.
292. The two-day classes are being offered a couple different time. I
enrolled for the Jan. 30-31 sessions (again, in case anyone is interested).
Candy
Yeah, I saw that. I believe they are offering it at the Vegas show as
well. I’m as yet unsure whether I am making the Tuscon show, but I
would like to keep posted on a meeting date at the Tucson show for
those of us on the list, I think it’s a great idea. Thanks, Mike.
I took the PMC workshop conducted by Eleanor Moty here in Tucson. She has
done two classes, $125 each for two days, and a third is scheduled on Dec 14
&15. We have sponsored this through Arizona Designer Craftsmen.
PMC is very interesting. It is creative to work with, it acts just like clay
and can take beautiful impressions. It is extremely porus and remains damp
for quite along time (reports out of the East say that jewelry made a year
ago out of this is beginning to mold). The PMC shrinks considerably during
firing, firing process is very long --about four hours, and it is extremely
costly.
However, we have had a mixture of metal and clay people in the seminars, the
clay people seem happiest with the product. Perhaps since they do not have
the casting available as we do, and know how to work with clay.
If you have any other questions, let me know. I found it exciting to try and
fun to work with, but doubt that I will be able to use it in my work.
Although the material is fine silver, it yellows under enameling. Further
firings also further reduce the size.
I took the PMC workshop conducted by Eleanor Moty here in Tucson.
snip
If you have any other questions, let me know. I found it exciting to try and
fun to work with, but doubt that I will be able to use it in my work.
Hi…I have been invited to take the PMC workshop with Tim McCreight
that he is offering in Portland OR in January. I have always been
puzzled by this product. As you mention, it is quite expensive, and it
seems as if most people that use it are duplicating work that can be
done with the usual forming techniques. Something doesn’t work here. Why
spend the extra money if you cannot get the extra return in the cost of
the finished piece?
Seems to me, being somewhat of an outsider in that I make equipment
rather than jewelry, is that PMC with it’s unique properties should be
used to make something that cannot be made, or would be very difficult
to make with conventional techniques. Only in this way will you be able
to get the cost back out of the material.
Possibly, this is a product that has yet to find it’s market?
Lee Marshall
Bonny Doon Engineering http://www.bonnydoonengineering.com
Designer & builder of metalsmithing equipment
You can get PMC info from Rio Grande, they are the only distributors in the
US so far. Also I have the little booklet and would send you a copy if you
want.
In short, PMC is a clay substance with either fine gold or fine silver as the
metal. The composition is a guarded secret by the manufacturers
(Japanese)(Mitsubishi). You mold the clay and then fire it in a tedious
process taking about 4 hours. It shrinks approx 50% ( the mysterious
contents) leaving fine silver or gold. So far, it has mixed results.
It was just released to the public this year, but last year agroup of highly
asteemed metal artists got to “play” with it at no expense to them. They
have mixed feelings. The shrinkage factor means it is not as reliable as
casting, the cracking factor is also an issue. It is extremely porous and
cannot be soldered. So you have to use your imagination to build in findings.
The fired metal is 80% as dense as conventional sheet or wire. It is not
recommended for applications requiring high tensile strength such as
findings, chains and settings.
You can form it by making sheets, wire, extruding through presses, press
into molds, just like clay. It must be kept moist and pliable.
It can be refired, but subsequent firings in our class showed additional
shrinkage. You can implant things into the material (items must withstand
kiln temps of 1650 for silver).
Finished pieces can be burnished or tumbled, polishing will put rouge in the
porus product.
I am not an expert, but more people are becoming familiar with PMC through
classes. Candy is going to take the PMC class in Tucson through RIO.
In a message dated 96-12-03 22:38:40 EST, you write:
Hi !
Could you tell me or direct me to more on this product.
The only place it is available in the US is Rio. 1-800-637-8303. Order a
catalogue and it gives a good general description of it. Also, someone at
Rio can probably tell you about it. They also have a website at http://www.riogrande.com.
It was invented in Japan. Is pure silver (or 24 k gold) mixed with a water
soluble binder. There is a 50% shrinkage rate after firing. They are
supposed to include instructions with purchase. The Silver runs about $32 an
ounce; the gold is more like $400, but is sold in 1/4 ounces.
Some more info, I just read from RIO catalogue on PMC: "because of its
porosity, PMC will “soak up” solder. They claim you need to burnish the area
to “close the pores” and reduce the “tendency” to absorbe solder. They go on
to say “use a delicate hand with the torch, removing the heat as soon as
solder starts to flow”.
Also, our experience as well as RIO’s info: PMC objects can retain pickle
unless thoroughly rinsed, neutralize the acid by oiling the pieces
in…bakingsoda or ultrasonic machine.
My feeling is, that even their booklet is cagey in this area.
Our experience, as was the case with Eleanor and the group that
"experimented" with the product last year, is that you cannot solder PMC.
The reason is simple, it is simply too porus, it absorbes the solder rather
than flowing between two joints.
Eleanor has found that she embeds little pieces of metal into the PMC prior
to firing where she will want to solder (earring backs, pin stems, etc), she
then has a piece of metal to solder on.
Once again, this is just my experience and I am reporting what she said and
did, perhaps RIO has come up with something nifty. However, look at the
pieces they show, not much soldering there.
Eleanor has found that she embeds little pieces of metal into the PMC prior
to firing where she will want to solder (earring backs, pin stems, etc), she
then has a piece of metal to solder on.
In a previous incarnation, I was involved with the automotive field. We
made cast aluminum centers for the steel rims that held the tires. The
aluminum center was “fancy”. We set steel insets into the molds, cast
the centers, machined the outside diameter which exposed the steel lug,
which then could be welded to the steel rim. We actually were able to
get a patent on it! It is obviously out of date at this point.
Interesting how work practices cross over.
Lee Marshall
Bonny Doon Engineering http://www.bonnydoonengineering.com
I really appreciate all this incite. I am still interested in “playing” with
PMC, regardless of all these negatives. I get bored easily and having lots
of different things to learn helps me stay enthusiastic. I have watch
polymer clay evolve of the past few years and it seems evolving as time goes
on and more and more people get involved with it. (I have never worked in
it, but have observed it “from afar”!) I guess that is another reason why
this interests me. I am curious to see where PMC ends up in the jewelry
and/or clay arts.
When you say to neutralize the pickled piece by “oiling” them, what does that
mean exactly? I always submerger my pieces in a baking soda/water rinse
after pickle, then rinse again in fresh water. Is this different from
"oiling"?
You can get PMC info from Rio Grande, they are the only distributors
in the US so far. Also I have the little booklet and would send you
a copy if you want.
In short, PMC is a clay substance with either fine gold or fine
silver as the metal. The composition is a guarded secret by the
manufacturers (Japanese)(Mitsubishi). You mold the clay and then
fire it in a tedious process taking about 4 hours. It shrinks approx
50% ( the mysterious contents) leaving fine silver or gold. So far,
it has mixed results…
Yes I would be interested in the booklet, e-mail or snail ?. what is
the cost of this clay in silver and gold ?
Thank you very much for you
Have Fun
Brandeil
#418-2000 Saddleback rd.
Edmonton, Ab
T6J-4S4
Canada