METAL-CLAY MULTIPLICATION. Start with one idea: Create an original piece of art using polymer clay, bake it,

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1 intermediate metal clay METAL-CLAY MULTIPLICATION With silicone molds you can form metal-clay multiples in a snap. Using different metal clays which shrink to varying percentages upon firing yields finished pieces of different sizes. by Pat Gullett Start with one idea: Create an original piece of art using polymer clay, bake it, and then make a silicone mold from that piece. Add a second idea: Use various metal clays (each with different shrinkage rates) to make multiple metal-clay elements turning those that shrink less into pendants and those that shrink more into earrings. Continue with a third idea: Make silicone molds from the sintered metal-clay elements and use the new molds to make even smaller metal-clay components for a daintier set of earrings. You could go on ad infinitum! Consider this about metal clay: One type shrinks as much as percent as it sinters; another, only 8 9 percent; and still others, somewhere in the percent range. (See The Shrink Factor, for which brand and type of clay ends up what size.) By taking advantage of what some may consider metal clay s drawbacks, you can turn a potential design disadvantage into a strength. Starting with a polymer-clay model means you can create an original mold with the exact look you want. You may experiment with the design without worrying whether the metal clay is drying out. When you are finished with this project, you will not only have a great-looking set of jewelry, but your mind will also be sharper when it comes to working with metal clay and factoring shrinkage into your designs. FCT-CRON0216_ART Kalmbach Publishing Co. This material may not be reproduced in any form without permission from the publisher. facetjewelry.com

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3 [1 2] Roll out and texture the polymer clay. Roll out 1 ounce (28g) of well-conditioned polymer clay using the thickest setting on a pasta machine (#1 on an Atlas ). If you are using playing cards, roll the clay 12 cards thick. Dust the polymer with cornstarch and place it onto a texture sheet. Roll over the polymer clay to impress the texture. [3 4] Cut out the main shape. Place a circle template with a 2-inch (5.1cm) diameter on top of the textured clay. Use a needle tool to scribe around the inside of the template. Leave the template in place and use the guides on the template to determine the center of the circle. Place two straight-edged tools along these guides; the tools should intersect at the center of the circle. Use a needle tool to mark the center. Remove the tools, template, and excess clay from the circle. Reserve the excess clay for later use. [5] Remove the center. Place a square inch (8.73mm) template over the polymer-clay circle, centering it on the mark you made in the last step. Cut out the square with a needle tool or craft knife. Remove the clay square and add it to your excess clay. Use a piece of dry paper towel to smooth the edges. [6] Create textured quarter-circles of clay. Using the leftover clay, cut out another 2-inch (5.1cm) circle. Remove the template and the excess clay. Place a piece of screen across half of the circle and lightly roll over it to texture the clay. Texture the opposite half with another piece of screen that has a different pattern. Position the edge of the second screen flush against the textured edge of the first one. Impress the texture in the clay with a roller. The clay may stretch when you texture it; if so, place the circle template back over the clay and trim the excess. As in step 5, cut a square from the center of the circle. Place the circle template back over the circle and use its vertical and horizontal positioning marks and a straight-edged tool to cut this circle into quarters. Select two of the clay quarters with different patterns. The other two will not be used and can be added back to your excess clay. [7 8] Glue the polymer pieces together. Apply a small amount of liquid polymer clay on the back of one of the quarter pieces. Place the glued side on top of the 2-inch (5.1cm) polymer circle, matching the notch for the center. Press the pieces together. Glue the back of the other quarter and position it opposite the first one. Press these pieces together. Set the textured polymer piece aside. [9 10] Make and add raised elements. Select several small objects such as those shown (an M from a rubber stamp set, a crescent moon, a polymer-formed spiral, and a trilobite fossil). Then follow the instructions for making Polymer-Clay Molds from Found Objects". Condition another 2 ounces (57g) of waste polymer clay, forming it into a block that is 5 8 inch (1.6cm) thick. Press the conditioned clay into the 82

4 mold, making sure clay goes into the deep sections. Carefully remove the clay piece from the mold. Use a craft knife to cut one raised polymer-clay element from the block. Using liquid polymer, glue the item on top of the textured polymer piece. Repeat with the other raised items on the block. Add any other embellishments to decorate the piece. If you want, you can cut a pie-shaped notch into it or add polymer balls of varying sizes. Bake the textured polymer clay. Bake the clay piece in a toaster oven that is dedicated to nonfood use. Follow the manufacturer s instructions for the clay used. [11 12] Make a silicone mold. Using a two-part silicone mold compound, take a walnut-size piece of each part and use your fingers to knead them together until they are mixed completely. Since the parts usually are two different colors, mix them until a uniform color is achieved. Working quickly, shape the molding compound so it is a little larger than the textured polymer-clay piece. Put it on your work surface. Place your baked polymer-clay piece face down on top of the compound and press until the top of the textured polymer-clay piece is flush with the top of the compound. Press firmly so all the textures are captured in the silicone mold. Let the compound set for minutes. It is cured when you press your fingernail into it and the mark heals itself. Gently flex the mold to remove the polymer-clay piece. [13] Make the metal-clay pieces. Roll out the metal clay. Start with approximately 14g of metal clay that shrinks in the 8 15 percent range. Working on a heavy plastic sheet that is lightly coated with olive oil, roll the lump of metal clay into a circle that is 4 playing cards thick. (See Making the Rounds, below, for tips on making perfect circles.) Place the silicone mold face up on the work surface. Silicone molds do not have to be oiled before using them with metal clay. Place the metal-clay circle on top of the mold and gently press down, making sure the metal clay gets into all the textured areas of the mold. Trim the excess metal clay from around the mold and the raised-square area in the center. Gently flex the mold, releasing the metal-clay piece. Place the metal clay on the oiled Making plastic. Allow the clay to dry as the rounds Place your metal clay on a lightly oiled piece of heavy plastic. Oil one side of another piece of heavy plastic and place it oiled side down on top of the clay. Always roll the metal clay with the plastic in place to keep the clay from drying out prematurely. Between the plastic sheets, place two stacks of 12 playing cards each on either side of the clay. Use an acrylic rod or piece of PVC pipe to roll over the clay. Remove three cards from each stack. Quickly pick up and rotate the clay and plastic 90 degrees clockwise. Roll the clay again. Remove three more cards from each stack. Rotate the clay and plastic another 90 degrees clockwise. Roll again. Continue this process of removing cards and turning the clay until you reach the desired thickness of the clay. Rotating the clay 90 degrees after each roll causes it to stay in a circular shape rather than elongating into a rectangle.

5 materials Polymer clay, 3 ounces (84g), any color (or waste) Liquid polymer clay Two-part silicone mold compound Metal clay, 14g (shrinkage rate of 8 15 percent) Metal clay, 28g (shrinkage rate of percent) Sterling-silver wire, 21 inches (53.3cm), 22-gauge 3 round beads, 4mm 3 sterling-silver spacer beads, 3 5mm Chain for necklace 2 ear wires Keum-boo foil (optional) tools & supplies Pasta machine* and/or deck of playing cards Acrylic roller or PVC pipe Cornstarch Texture sheet Circle template Square template Needle tool 2 straight-edged tools Paper towel 2 pieces of wire screen, different patterns Small objects: rubber M stamp, crescent moon, polymer-formed spiral, trilobite fossil, or others Craft knife Hotplate or toaster oven* 2 heavy plastic sheets Olive oil Jeweler s file, flat Kiln with ceramic-fiber shelf Brass brush Wire cutters Round- and chainnose pliers Steel bench block Hammer Keum-boo tools (optional) Tumbler with stainless-steel shot and burnishing compound (optional) Liver of sulfur (optional) * Dedicated to nonfood use. The set The pendant and earrings in this article use basic wirework techniques for finishing. To make the necklace, use the large metal-clay disk and the instructions for making a bail as outlined here. Finish by sliding a chain through the wrapped loop. To make the earrings, use the medium disks. Use the bail-making technique to make stems for the earrings. Attach ear wires to the wrapped loops. If you want smaller earrings, make silicone molds from your medium metal-clay disks. No matter what type of metal clay you use, the new disks, once sintered, will be smaller. is, or speed up the process by placing it on a hotplate or in a toaster oven set to low. Repeat using metal clay that shrinks percent to create two disks to use for earrings. Finish and fire the clay. When the metal clay is leather hard, use a flat jeweler s file to sand the outer edge of the element and the inside edges of the square center. Place the metal clay on a ceramic-fiber kiln shelf and fire it according to the clay manufacturer s directions. You may have to do separate firings for clays that require different firing times and temperatures. When the metal clay is cool, use a brass brush to burnish away the white appearance of the sintered silver, but if you want to do keum-boo on some of the areas, do it before burnishing. For more information on this process, see Celie Fago s book, Keum-Boo on Silver. For a shinier finish, place the burnished pieces in a tumbler with stainless-steel shot and burnishing compound for minutes. Rinse and dry the pieces after tumbling. Add a liver of sulfur patina if desired. Be sure to follow the manufacturer s directions for the product you are using [1 3] Make a bail. Use wire cutters to cut 7 inches (17.8cm) of 22-gauge wire. Make a wrapped loop at one end [1]. Slide a 4mm round bead and a 3 5mm sterling-silver spacer bead onto the wire. Grasp the wire with roundnose pliers about 3 4 inch (1.9cm) below the spacer. Bend the end of the wire around the jaw of the pliers until it forms a U shape [2]. Slide the largest metal-clay disk into the U. At the top edge of the disk, wrap the free wire end around the wire stem three or four times [3]. Cut off the remaining wire, leaving a 1 2-inch (1.3cm) tail. To enhance the appearance of the wire, place the tip of the tail on a steel bench block and flatten it with a hammer. Polymer-clay molds from found objects Condition 2 ounces (57g) of waste polymer clay. Shape the conditioned clay into a block that is 5 8 inch (1.6cm) thick. Press an object into the clay so it forms an impression. Don t press it in too far or you may not be able to remove it without marring the clay. Remove the object. Repeat with other elements, leaving a small space between them. You can also use a needle tool to draw a figure into clay, as was done with the Egyptian eye (the element far right in the photo below). Bake the clay block in a toaster oven that is dedicated for nonfood use, following the manufacturer s instructions for the type of clay used. When the clay block is finished baking and completely cool, dust it with cornstarch. 84

6 The shrink factor: Experiments were made with seven different types of metal clay to give you a visual tutorial of the shrinkage phenomenon. We made a polymer-clay template and one silicone mold of the template. Each type of clay was pressed into the mold, removed and allowed to air dry, and then fired according to the manufacturers instructions. Our kiln is a PMC Sierra, model #360F-SA-120-P-00. Finished with liver of sulfur, the results are shown below. + Polymer-clay template Diameter: 2.0 inches (5.1cm) Silicone mold Diameter: 2.0 inches (5.1cm) = PMC Standard 25 30% expected shrink rate 30% actual shrinkage Fired diameter: 1.4 inches (3.6cm) PMC % expected shrink rate 16% actual shrinkage Fired diameter: 1.7 inches (4.3cm) PMC % expected shrink rate 16% actual shrinkage Fired diameter: 1.7 inches (4.3cm) Art Clay Regular 8 12% expected shrink rate 12% actual shrinkage Fired diameter: 1.75 inches (4.5cm) Art Clay Slow Dry 8 12% expected shrink rate 12% actual shrinkage Fired diameter: 1.75 inches (4.5cm) Art Clay 650 Low Fire 8 9% expected shrink rate 10% actual shrinkage Fired diameter: 1.8 inches (4.6cm) Art Clay Slow Dry 650 Low Fire 8 9% expected shrink rate 12% actual shrinkage Fired diameter: 1.75 inches (4.5cm)