Goldie BronzeTM is a beautiful material. When constructing a bezel for a cabochon gem we need to treat the bronze clay differently than silver clay. A common method used with silver clay is to make a plug from jeweler’s investment to stop the metal clay bezel from shrinking smaller than the size of the stone. However, jeweler’s investment creates a nasty crusty black layer on fired bronze clay that can be impossible to remove. This dilemma led me on a quest to find a repeatable process for making bronze bezels. After months of experimentation and a box of failures I now have a reliable method that works every time!
This how-to article is made possible by Robin Ragesdale and her business www.evenbetterimages.com
Project by: Robin Ragsdale
Project editors: Jeannette Froese LeBlanc and Margaret Schindel.
MATERIALS AND EQUIPMENT: (click here)
Make the dummy stone: Trace the base of your cabochon on paper. Scan and enlarge the tracing at 108% and print it out on paper. Cut out the tracing to create a template and write “108%” on the top. (Photo 1)
Roll out the Creative Paperclay to about 1/4 inch thick. Lay the template on top and cut around it with a craft knife, leaving a 3mm border of Paperclay around the template. Remove the template and allow the Paperclay to dry completely. Drying time can be decreased by placing in a toaster oven or on top of a mug warmer. Flip the clay often to avoid warping.
When the Paperclay form is dry, place the template on top and draw its outline on the dried clay with a pencil. Remove the template and sand the Paperclay shape to match the penciled outline. Mark the sanded shape “108%” on top. You now have a working placeholder or “dummy stone.”
Cut a strip of masking tape as wide as the height of your dummy stone. Wrap the tape around the outer edge of the dummy stone in a single layer and trim the tape so that the ends meet flush with no overlap. Apply a thin layer of olive oil to the tape.
Make the bezel and support frame:
Roll out a long, narrow sheet of bronze clay to 1 card thick. Using a straight edge and knife, cut a long strip as wide as the height of the dummy stone. Carefully lift the strip from your work surface and gently wrap it around the dummy stone. Cut where the ends meet with a very slight angled overlap. Add a little PasteMaker and blend the seam together with a clay shaper or your brush. Allow the bezel to dry completely and then smooth it with fine and superfine sponge sanding pads. (Photo 2)
Here’s the tricky part. Very carefully slide the tip of your knife blade between the tape and clay. Taking your time, slowly and gently loosen the bezel from the dummy stone but do not remove it. This is an extremely delicate operation. If you get a crack or tear, you can repair it with a little clay paste and allow it to dry again. Then slide the bezel down so that the top 2 mm of the dummy stone is exposed above the bezel.
Roll out some fresh clay to 2 cards thick. You can add a shallow texture or leave it smooth. Set your bezel (with the dummy still inside) on the clay and gently press the bezel down to embed the lower edge in the fresh clay. Brush a bit of PasteMaker into the seam around the outside of the bezel base. Use your knife to cut around the clay about 4mm outside the bezel to make the bezel frame. Remove and store the unused clay and let the setting dry completely. (Photo 3)
Turn over the setting and cut out a section from the bottom that is a bit smaller than the inside edge of the bezel. Gently press on the bottom of the dummy stone through the hole you just cut out and try to push it all the way out of the setting from the back. If the dummy does not move easily, don’t force it; use the tip of your knife to gently loosen it from the bezel and try again.
After the dummy is removed, very carefully and lightly sand the inside with sponge sanding pads, enlarging the hole in the base to make it flush with the inside of the bezel. Then replace the dummy for stability and, holding your piece by the dummy, sand the outer edges of the frame, ensuring that the border is an even width all the way around the bezel. If you didn’t texture the clay earlier you can etch or scratch a pattern into the frame now if you want. (Photo 4)
Make the backplate, embed the bezel and add the bail:
Choose textures for both sides of your backplate. Roll out some fresh clay to 4 cards thick. Place it on the texture sheet for the back between two 3-card tall spacers, making sure that the spacers as well as the clay are on top of the texture. Place the front texture sheet face down on the clay and roll the clay between the two textures. Alternatively you can roll out the clay to 3 cards thick on just the back texture and then impress the front of the clay with something like a leaf or shell if you prefer. (photo 5)
Remove the top texture and, leaving the clay on the back texture, use a small shape cutter or a craft knife to cut out a hole in the center of the clay to create a window in the backplate. This cutout can be any shape you like but it must be smaller than the inside of the bezel so that the backplate can hold the cabochon in place from the back. Add a little PasteMaker to the bottom of the bezel frame (with the dummy stone still inside for support) and gently press it onto the clay, centering it around the cutout. Trim the backplate to the size and shape desired (taking care not to damage your texture sheet) and let it dry on the texture sheet.
When the backplate is dry, carefully remove it from the texture sheet. Holding the piece by the dummy stone and the outside edges of the backplate, refine the outside edges using sponge sanding pads or a salon nail board.
To create the bail for a pendant, roll out and texture a slab of bronze clay 2 cards thick and cut out a small oval or teardrop shape. Curl one end of the shape cutout around a coffee stirrer straw and let dry. After it is dry, refine the edges. Use PasteMaker to moisten the surfaces of the backplate and bail where they will be connected. Add a small amount of clay paste to the attachment point of the bail and gently press it down on the backplate and allow to dry. (Photo 6)
Remove the dummy stone from your pendant. Leaving the masking tape attached, place the paper dummy in a firing container on a ½-inch layer of activated carbon. Add another ½-inch layer of carbon and cover the firing pan with the lid. Fire at full ramp to 1510°F/821°C for 45 minutes. Let the kiln cool to at least 200°F/93°C before removing. You now have a carbon dummy. It’s very fragile so handle with care! (Photo 7)
Roll a very short length of masking tape into a loop and use it to attach the back of your cabochon to a piece of paper. Use your craft knife to cut as closely and accurately around the base of the cabochon to make as exact a paper template as possible. Remove the tape from both the paper template and the stone. Write “top” on the side of the template that was attached to the tape.
Smooth a small amount of school glue on the entire back surface of your paper template, glue it to the top of the carbon dummy and let the glue dry. Sand away the outside of the dummy to the match edge of the paper template. Center the carbon dummy in the setting. (Photo 8)
Refill your firing container with ½-inch of carbon. Cut a piece of ceramic kiln paper larger than the window (hole) in the backplate of your pendant. Place the kiln paper on the carbon and center the pendant on the paper. The purpose of the kiln paper is to stop carbon granules from getting inside the bezel and potentially blocking shrinkage.
Fold a square of fine stainless steel mesh into a cage at least 1/4 inch larger than your pendant on all sides and tall enough to not press down on the bezel. Place this cage on top of your pendant. Do not add more carbon or cover the pan with the lid. (Photo 9)
Fire your pendant according to the clay manufacturer’s instructions and your experience with your individual kiln. The first firing should most likely be to a target temperature of 662°F/350°C with a hold time of 30 minutes. After firing, allow the kiln to cool to 300°F/149°C or lower before removing the container from the kiln. For the second firing add another ½-inch to 1-inch layer of carbon and cover the container with its lid. Place it back into the kiln and fire according to the manufacturer’s instructions and your own experience. I fire mine to 800°F/427°, hold for 30 minutes to saturate with heat, then increase the temperature at full ramp to 1510°F/821°C and hold for 1 hour and 40 minutes.
Remove the container when the kiln temp cools to 300F/149°C or lower. Use a slotted metal spoon to lift your finished piece out of the carbon. The carbon dummy should still be inside the bezel and the bezel should have shrunk snugly around it.
Test-fit the cabochon and make adjustments if necessary:
Check that your cabochon will fit in the bezel. If it is a slightly loose fit don’t worry. If the bezel has warped, straighten the edges with your burnisher. The bottom may be warped a bit. If so, use the grinding stone to make it as level as you can. If the stone still rocks in the setting, don’t worry. You’ll be able to fix that later. Remove the stone and set it aside. If the bezel is too tall for your stone sand it down to the correct height using files or sanding sticks. Put the cabochon back into the setting often to check the height so you don’t remove too much material from the bezel.
Rinse your pendant with water and then use a rotary tool with the radial disc attachment to clean all surfaces of the metal. Then switch to the steel wire brush wheel attachment and burnish the metal well. The amount of sanding, grinding and burnishing is completely up to you. If you want a high shine, sand and burnish until you are satisfied. (Photos 10 & 11)
When you are happy with the finish of the metal, mix equal amounts of the two-part epoxy and apply the glue sparingly to the base of the setting inside the bezel. (Photo 12) Place your cabochon in the setting and press down firmly. Set it aside for two hours or place it in a warm (125°F/52°C) toaster oven for 30 minutes to cure the epoxy. If you use a toaster oven, allow to cool completely before proceeding.
To burnish the bezel around the stone, take your time and carefully press the bezel against the stone using your burnisher, taking care to keep the stone centered in the setting throughout this process. Begin by pressing the bezel at the 12 o’clock position. Then press at the opposite position (6 o’clock) and then at 3 o’clock and 9 o’clock. Continue around the stone in this manner until the entire bezel sits snugly against the stone. (Photo 13)
Sealing the surface of the bronze metal is optional. If left unsealed, the color of the metal will darken over time. You can use your favorite sealing medium on the metal after you set the stone but be careful not to get any on the stone itself. I use microcrystalline wax (e.g., Renaissance Wax).
About the Artist: Robin Ragsdale is a metal clay jewelry designer and also has 30 years experience as a graphic designer and photo retoucher. She has a second business servicing the photo needs of fellow artists. For your photographic needs, check out her website www.evenbetterimages.com!
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