Fine Silver Granulation – Part 2

This article is the second of two parts Fine Silver Granulation Project by Sandra Buchholz. Click here for the first part of the project.

GRANULATION Overview

Granulation 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

(Previous steps can be found here)

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.

1. Using a pin stem or needle as a mandrel, and 26 ga. round wire, wrap the wire around it in a tight coil.

2. 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)

3. 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.

4. 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.

5. 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)

1. 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.

2. 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.

3. 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.

4. 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.

5. 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.

6. Continue making the triangles all around the piece.

7. 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.

8. Set the earrings aside and let them air dry for about 5 to 10 minutes.

STEP 6: Fusing the Granules

1. 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.

2. 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.

3. 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).

4. 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  turned 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.)

5. 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.

6. 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.

7. 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

1. 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)

2. 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.

3. 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.

4. 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.

5. 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.

6. 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

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 Trinket kiln) *** Charcoal block Small piece of ceramic tile Tweezers

To Finish Earrings

Either posts or wire hooks Medium solder Stone setting tools

Footnotes

* 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