GRANULATION OverviewGranulation involves placing and fusing tiny
balls of silver on the surface of the backsheet in a preplanned
design. The mixture of Hide Glue, flux and water is used to
temporarily hold the granules in place until they are fused.
STEP 4: Acquiring the Granules
Granules can be either bought or made by hand. The obvious advantage
to buying granules is that you save a great deal of time that you
would otherwise spend in making them, and that they will be very
uniform in size. Uniformity is important because it affects the
final look of the design. The downside is that they are expensive,
and usually need to be purchased in larger quantities than you would
need for one project. For this project you would need about 3 Dwt.
of Fine Silver granules. They generally come in 3 sizes-Large (.032)
Medium (.024) and Small (really tiny–. 0 16) The large size was
used for these earrings. (See supply list for source of granules).
Making your own:
The main advantage to making your own granules is cost. After some
experimenting, you can also make granules of different sizes, and
find the size that suits your work better than those that are
purchased. You can also make as many as you need, as you need them.
Some experimentation and practice is very helpful. The downside is
time and getting uniformity
Granules are made by coiling fine silver wire around a pin stem or
needle that is used as a mandrel. The final size is a variable of
the thickness of the wire, the diameter of the ‘mandrel’ that is
used for coiling the wire, and the point on the curve of the coil
where the wire is cut. To maintain uniformity, the wire should be
cut at precisely the same point in the curve each time.
-
Using a pin stem or needle as a mandrel, and 26 ga. round wire,
wrap the wire around it in a tight coil. -
Remove the coil from the pin, and stretch it out slightly so that
you can get a small cutting tool between the loops. Snip the top of
each loop (do a few and see if you are getting the size you want) -
Spread the little curls out on a charcoal block, -don’t put them
too close to each other or they will tend to roll around and merge
when they are heated, giving you granules that are much too big.
TIP: It is helpful to carve a ridge around the top of the charcoal
block, about 1/4 from the edges. This provides a channel for the
granules to roll into and makes them easy to retrieve.
-
Using a small tip on your torch, heat each granule briefly until
it turns into a perfect ball. Try not to bring the flame too close
to the granules because the force of the flame will blow the
granules around, sometimes causing them to collide or to fly off the
charcoal. Remove the heat promptly when the ball is formed. -
Once you have found the correct size continue to make granules
until you have as many as you need. As mentioned before, you don’t
need to do them all at once but can make them up in batches as you
need them.
STEP 5: PLACING THE GRANULES (Figs.3,4,4A)
-
Make sure the backsheet is flat, clean and as smooth as you can
get it. Pickle it and then be sure to clean it in hot soapy water
and rinse in clear water to remove any traces of pickle. Try not to
get any fingerprints on it. -
Have handy the Hide Glue mixture, a small amount of water, the
000 brush and either another fine brush or fine tweezers. It is
helpful to work on a clean piece of paper toweling. -
Pick up a small amount of Hide Glue mixture on the brush, and
then pick up a few granules. Place them on the backsheet, starting
at the outside wire. Place a row of granules all around the inside
of that wire. This will form the first line of your pattern. Use the
Hide Glue sparingly, and dilute it with a little water on your brush
when necessary. Give the granules a chance to dry a little before
going on to the next line. This will help prevent them moving about
when you continue the pattern. I have found it helpful to work on
both earrings at the same time, alternating them- do the outer
circle on one earring, set it aside and do the other, and then go
back to the first one, etc. -
Making the triangles: Place five granules under the first row.
Make sure the granules touch each other and the row above them. They
will settle into the angles made by the joining of the above
granules. Next place four granules below them, then three, then two
and then one. That completes the first triangle. -
To start the second triangle, skip one granule space, and then
repeat the procedure. The pattern will look different depending on
where you place each triangle. Try to be consistent in how far apart
they will be. -
Continue making the triangles all around the piece.
-
Place a row of granules around the wire that surrounds the bezel.
Then make small triangles of three granules each, spacing them
evenly so that the point of the little triangle points to the
opening between two larger ones. -
Set the earrings aside and let them air dry for about 5 to 10
minutes.
STEP 6: Fusing the Granules:
-
Wait until the kiln is very hot. Do one earring at a time. Place
the earrings on the small piece of ceramic tile and place the tile
under the kiln so that the heat from the kiln will begin to dry the
glue mixture. -
Next, put the cover on the kiln, and place the tile with the
first earring on it on top of the cover. Let this heat up for a few
minutes. DO NOT RUSH THIS PROCESS! When the glue mixture starts to
turn a little brown, gently and carefully slip the metal piece off
the tile and onto the kiln cover. Try not to jar it, as the granules
become loose as the glue mixture burns off. -
When the glue mixture turns dark brown (don’t get alarmed)
carefully lift off the backsheet holding it perfectly horizontal so
as not to disturb the granules, and place it in the hottest part of
the kiln (usually there is a bright hot spot which is visible). -
Cover the kiln for a few seconds while lighting your torch.
Remember to use a large tip with a very soft flame. Check the piece
to see whether the glue has all burned off. When the piece looks
silvery again, it is time to begin heating the granules to fuse
them. (Sometimes the glue will send up black smoke as it is burning
off-do not worry about this.) -
Use the same technique as described before. Hold the flame at
right angles to the piece, and allow only the feathery tip to come
in contact with the metal. Start by slowly describing a circle
around the outside of the piece, to allow the heat to build up
evenly while the kiln provides bottom heat. Every once in awhile,
pass the tip of the flame over the metal piece itself–in a kind of
sweeping, swooping motion that does not concentrate the heat in any
one place. DON’T TRY TO RUSH THIS PROCESS EITHER! Work slowly and
methodically, heating around and then over the piece. -
When the metal begins to shimmer and the granules start to look
like they are lighting up, gently stroke over each section of the
granules until you have covered the entire area.Withdraw the heat
quickly, and remove the piece from the kiln, letting it air-cool for
awhile, Repeat the same process for the second earring. -
Now comes the really hard part. It is essential to make sure that
all the granules are in fact, fused to the backsheet. With a sharp
tool, such as tweezers or a scribe, push each granule to see if it
is securely fused. It is not unusual for one or two or several
granules to come off even when others right next to it are fused.
Remove any granules that are not fused, reglue them and repeat the
whole process. It takes some practice and experience to determine
the exact point of fusing.
TIP: Until you get experience in determining whether fusing has taken
place while the piece is hot, it is probably better to underestimate
the time and then repeat the process if necessary. If the piece gets
overheated, the granules will melt and the piece will not be
salvageable.
STEP 7: Finishing the Earrings
-
Trim the excess metal from the backsheet by snipping around the
outside wire ring. Keep the cutters at right angles to the piece and
move the piece into the cutter to avoid any undercut. File and sand
around the outside edge to get a perfect circle.(Fig.5) -
Remove the ochre from the back of the piece by painting it with
paste flux and heating it until the flux becomes shiny. While hot,
plunge it in pickle, then rinse and use a brass brush to clean off
residual ochre. This may have to be repeated a few times. -
To bring up the fine silver and give the piece a soft look, coat
it with paste flux, heat the flux to a shine and pickle. Then use a
brass brush to bring out the sheen. Rouge can also be used on the
granulated surface, but NOT TRIPOLI or any abrasive as that will
erode the granules. -
Sand the back of the piece and polish to a satisfactory shine.
Solder the posts with medium solder. This should be the last
operation before setting the stone. -
Set the stones.
TIP: because the earrings are fairly heavy, they will hang best when
clutches are used on the posts. If you prefer, an Omega earring back
could also be used.
- Sit back and enjoy your beautiful granulated earrings.
For an excellent article on high karat Gold granulation, see Bauer,
Cecelia, Granulation in the Hoover and Strong Catalogue, 1996-1997,
p 21. For an excellent article on Sterling Silver granulation, See
Cogswell, John, Sterling Granulation in. Metals Technic, Brynmorgen
Press, 1992. P.3.
SUPPLY LIST
Sandra Buchholz
Fine Silver Granulation
SUPPLIES NEEDED
Silver sheet-24 gauge: two pieces approx. 1 1/4 inches square
Fine Silver round wire-22 gauge
Fine Silver-26 gauge bezel wire or make your own bezel
Fine Silver granules. *
Two 6mm. stones
Ochre
Steel bench blocks
TO PASTE GRANULES ON BACKSHEET
Hide Glue **
Liquid Flux
Eyedropper
One or two 000 paint brushes
Fine tweezers (optional)
TO FUSE GRANULES Torch with large tip (#I Tip for Smith torch; #7 for
Little Torch) Lightweight jeweler=E2=80=99s kiln (sometimes called Tri=
nket
kiln) *** Charcoal block Small piece of ceramic tile Tweezers
TO FINISH EARRINGS Either posts or wire hooks Medium solder Stone
setting tools
- A reliable source for granules is: STM (914-273-5500/fax
914-273-2065) They are located in Armonk, NY, and have a brochure
detailing size, costs etc., which they will send upon request.
** Available from Rio Grande, NM, or Metalliferous, NY
(212-944-0909) *** Available in hardware stores