I tried sterling silver granulation,and I used propane with
compressed air which worked fine, so oxygen and propane should
work well too.
Greetings: i made a batch of sterling Granules with propane
…discovered that the pickle had been contaminated by
(someone)…so now my granules are copper coated…so i made
an additional batch…changed out my pickle and to my suprise
about half of the granules seem to have an oxide or cuperic
coating on half of the sphere (perhaps were they sat in the
little divits in the charcoal block)…Does this mean I
overheated when forming? Or are the copper tongs used in the
pickle after it was contaminated somehow affecting my granules
and my frustration limit? Is there a fixit…or is bright
dipping the only bandaid? Any feedback would be “cool-it” to my
fire…!
Ironically, when I do fine silver granulation, I purposely
copper plate my granules. It’s the copper that makes them fuse.
It burns off during the granulation process.
Hi Eric-- Try putting the granules on a flat piece of charcoal(
no little holes) and reheating them. If you carve a border
around the edge of the charcoal it will help minimize the
granules rolling off from the heat. Make sure the heat gets to
the affected side of the granules. Good Luck Sandra
so now my granules are copper coated.... to my suprise about
half of the granules seem to have an oxide or cuperic coating
on half of the sphere Is there a fixit....
Hi Eric - a couple of things for your consideration:
talk to your metal supplier; I have bought fine silver
cloisonne wire in the past only to find out that when I wanted to
use the same wire for granulation, the formulation contained some
contaminates. They didn’t affect the enamelling process, but did
affect the granulation process. Not a big deal - the supplier
replaced all my metal without a complaint.
If it is truely copper on the outside, you can use this
coating as the copper necessary to create the eutectic reaction
that granulation relies upon. Simply remove the copper component
from your mix (you know, that concoction of hide glue, copper
salts, and water, etc.) and you should be okay. This process was
taught as an alternative method when I took my workshop.
Hi Eric, my sterling “shot” comes in various colors when taken
out of pickle. After the shot is soldered to whatever piece, and
polished, - using bobbing compound and then Zam- it’s just as
shiny (silver) as the rest of the piece.
You have to heat the sterling enough that it will melt, I
haven’t found that there is such a thing as overheating "shot, "
but, who knows, I may be wrong about that.
Fine silver,and sterling silver do not need to be copper coated
for the granules to fuse. However, 22K gold granules do need to
be coppercoated. Sterling is a little more difficult to
granulate with–John Cogswell has an excellent article on
Sterling Silver granulation in Metals Technic 1992 Brynmorgen
Press. Also see the September Lapidary Journal for a (my)
workshop on Fine Silver granulation. All things being equal;, I
was just informed that it will be split between the September and
October issues. Sandra/ElegantBee
i made a batch of sterling Granules with propane
....discovered that the pickle had been contaminated by
(someone)....so now my granules are copper coated.....so i
made an additional batch.....
Why? Don’t you WANT them copper coated? Seems to me that’s
part of the essential process of granulating silver. Leastways
the way I’ve always done it, specifically involved some nicely
used pickle and intentional iron to copper coat em
deliberately… Thats what makes em granulate…
..changed out my pickle and to my suprise about half of the
granules seem to have an oxide or cuperic coating on half of
the sphere (perhaps were they sat in the little divits in the
charcoal block)
The upper half of the granual, exposed to air, get nicely fire
scaled. The lower part, protected by charcoal, stayed clean.
.......Does this mean I overheated when forming?
Overheating? You’ve got to melt em, don’t ya? You’ll find, in
the end, that that fire scale on the grains does not get in the
way. Once you’ve fired the grains on your base piece and
pickled again, this time in non contaminated pickle, please, it
will clean up nicely enough.
To solve the copper plating prob: I think all you need to
do to remove the copper plating on your granules is to brush
them with a soft brass brush. This should wipe off any
unwanted residue from the alloy. Technically, one anneals
and pickles the silver several (4-8) times with brushing in
between to raise the silver content to the surface which
produces a very white soft finish when you remove the metal
from the pickle. After quenching it in the pickle as well.
This process is used especially in Kum Boo when the 24k leaf
is fused to silver.
Hi Bob-- There is a dragonfly that is granulated and is made is
fine silver on my site in the orchid Gallery. In the Sept,
Lapidary Journal I will have a workshop on Fine Silver
granulation. You can also find examples of gold granulation in
Oppi Untract/s book, and in many books on working in gold. Sorry
I don’t have any specific titles handy to give you. I’m happy
to answer any questions you may have. Sandra Buchholz/ElegantBee http://www.ganoksin.com/orchid/sandrab.htm