Open Lentil with Floating Pearl

Transcription

1 INTERMEDIATE Open Lentil with Floating Pearl A hollow bead with a hidden copper wire makes a pearl appear to levitate. by Pam East FCT-CRON0316_ART113 Pearls are a snap to set, and they add an undeniable richness to your jewelry. I m a big fan. For this project, I wanted to use a good-sized pearl and make it appear to float within the piece the depth of the lentil s interior adds to the illusion. The copper s deep patina provides a stunning contrast to the pearl s luminescence. You can make the piece with either Art Clay Copper or COPPRclay. For the most part, the instructions are the same; however, there are a few firing and handling differences between the two. Art Clay Copper feels very firm out of the package. Much like polymer clay, you ll have to knead it to soften it. COPPRclay is a little softer and has a slightly oily feel. If you re using a different brand of clay, check the manufacturer s instructions carefully. Always start by having your tools ready before opening your clay Kalmbach Publishing Co. This material may not be reproduced in any form without permission from the publisher. facetjewelry.com

2 An artfully concealed wire makes a pearl seem to float within the 2-in. (51 mm) pendant s window. 43

3 Part 1: Lentil Roll and texture copper clay. Use natural hand balm and a toothbrush to lightly oil a texture stamp [1]. Go easy with the balm; you want the barest coating. Too much release agent can cause your leftover clay to become crumbly. On a nonstick work surface (I use plastic notebook dividers cut into quarters), roll the clay to 8 cards thick [2] if you re using Art Clay Copper (ACC). (You can reduce this to 6 cards thick if you re using COPPRclay or another clay that doesn t lose surface during firing). Move the clay to your stamp, and use a plastic roller to firmly roll over the clay to texture it [3]. Cut two lentil halves. Use a circle template and a needle tool to cut two circles from your textured clay. Make the circles in. (41 mm) if you re using ACC or in. (44 mm) if you re using COPPRclay. NOTE: COPPRclay shrinks more than ACC. For any brand of clay, check the manufacturer s shrinkage guidelines. Cut a in. (21 mm) circle in the center of one of the lentil halves [4]. This will be the front of the pendant; the lentil half without a hole will be the back. Form the lentil halves. Lay the front and back lentil halves over the wide end of a plastic Easter egg [5]. Use your fingers to gently form the clay to the egg. The edges of the clay must be flush to the egg, or you ll have trouble fitting the lentil together later. Allow both pieces to dry completely. NOTE: Air-dry the lentil halves for 24 hours rather than trying to speed up the drying by using a dehydrator. If you try this, the pieces may warp, which will make it harder for you to fit the lentil halves together. Sand the lentil halves. Lay each lentil half on a piece of 220-grit sandpaper secured to a flat, hard work surface. Using a circular or figure-8 motion, sand the halves until their edges lay flat against the surface [Figure]. SAFETY NOTE: Some people find copper clay dust irritating. You may want to wear a dust mask while sanding. Hold the two lentil halves together to check the fit. They should be the same size without any overhanging edges. If one half is larger than the other, continue sanding it until the halves match. The edges of the Figure textured clay may be ragged at this point; we ll fix that later. Refine the hole s edges. Use files and/or a damp sponge-tip applicator to clean up the edges of the hole in the front lentil half [6]. 44

4 Part 2: Pearl wire Select the wire that will hold your pearl. ACC uses an open-shelf firing method, so you ll lose some material when the copper clay oxidizes in the kiln. For this reason, you need a slightly larger gauge for your pearl wire when you re using ACC than you do for COPPRclay. For ACC, use 18-gauge (1.0 mm) dead-soft copper wire. For COPPRclay, use 20-gauge (0.8 mm) dead-soft copper wire. NOTE: The copper wire must be 99.9% pure and dead soft, or it will break after you fire the pendant. Keep in mind that if you have to refire the pendant, the wire will be more likely to break after a second firing. Copper wire from a hardware store or other nonjewelry supply source is more likely to be an alloy than pure copper. Notch the lentil halves. Position the lentil halves together, lining them up as you want them to be in the finished piece, and determine where the top of the pendant will be. Use a small round file to file a notch through the edge of both pieces so you ll be able to match up the halves again [1]. Mark the position of the pearl wire. Look straight down at the hole in the front lentil half, and use a needle tool to mark the hole s center point on the back lentil half. Set the front half aside. NOTE: The mark may not be exactly centered on the back lentil half; it s more important that the mark is centered in the opening of the front half. Cut the wire. Cut a 1-in. (25.5 mm) piece of dead-soft copper wire. Use chainnose pliers to bend the wire 90 about 2 mm from one end [2]. Make paste. Put a small piece of copper clay into a glass or plastic dish. Use a spatula and distilled water to turn the clay into a very thick paste. The paste should not drip, run, or flow. The consistency should be like toothpaste or cake frosting. NOTE: Unlike silver clay, copper clay does not adhere well to itself and requires a great deal of reinforcement using thick paste and softened clay. Attach the wire to the back piece. Make a small ball of clay, and push the bent end of your wire through the center of it. Use a damp sponge-tip applicator to moisten the inside of the back lentil half. Rub the applicator around to create a wet, muddy surface [3]. Use some of the thick paste to attach the ball of clay holding the wire to the back lentil half [4]. Position the front half over the back half to check the placement of the wire. Use a rubber clay shaper to blend the ball of clay into the back lentil half [5]. Allow the piece to dry completely. You may use a dehydrator at this point. Reinforce the wire attachment. Use the sponge-tip applicator to muddy the surface around the wire. Apply additional softened clay around the wire, and use the clay shaper to smooth the paste, creating a seamless expanse from the wire to the edge of the lentil half [6]. Allow the piece to dry completely. Refine the back lentil half. Clean excess clay off the wire and smooth the reinforcement using various finishing tools, such as the damp sponge-tip applicator and/or sanding swabs. NOTE: Take care not to sand all the way down to the lentil half s original surface. The built-up clay reinforcing the attachment of the wire must remain. 45

5 Part 3: Assembly Make the bail. Bend a 1-in. (25.5 mm) piece of 16-gauge (1.3 mm) copper wire into a U around the wide end of one jaw of large roundnose pliers. Using chainnose pliers, bend out the ends of the U to create feet that will hold the bail in the lentil [1]. Notch the lentil halves. Put the lentil halves together, aligning the notch you filed. Using the bail as a guide, file a second notch in the top of the lentil halves [2] so that the two notches accommodate the stems of the bail; the bail s feet will fit inside the edge of the pendant. File grooves for the bail s feet. At each notch, file a groove into the flat surface of the back lentil half [3]. Repeat with the front lentil half. Place the bail s feet in the grooves, and fit the halves together to check the fit. NOTE: The front and back halves should fit tightly to each other and around the bail. File to make any necessary adjustments. Set the bail. Use the sponge-tip applicator to dampen the grooves on the back lentil half. Add a bit of paste to the grooves, and set the bail in place [4]. Use additional paste as needed to keep the bail from falling off. Join the lentil halves. Dampen the inner edge of the back lentil half, then add a very thick layer of paste all the way around [5]. Dampen the inner edge of the top half, and join the two pieces. There should be so much paste that it squishes out when you press the pieces together. Holding the two halves firmly together, use a damp flat #4 brush to smooth the excess paste around the edge of the lentil [6]. Taking care not to disturb the pearl wire, use the damp brush to smooth the paste around the inner seam [7]. Use additional paste around the inner seam to reinforce the join. Allow the piece to dry completely. Refine the lentil. Sand and smooth the lentil s outer edge. Use paste to fill any gaps and reinforce any weak areas. Pay special attention to the area around the bail; there shouldn t be any gaps. Allow the lentil to dry completely. Fire the lentil. How you fire your piece will depend on the brand of clay you re using. I ve included the methods I use 7 for firing ACC (see Open-Shelf Firing, next page) and COPPRclay (see Firing in Carbon, next page). If you re using a different brand of clay, check your clay manufacturer s firing instructions. The back of the pendant is domed, as in a classic lentil form, and richly texured. 46

6 open-shelf firing Art Clay Copper (ACC) should be fired on an open shelf in a preheated kiln. It will shrink approximately 10%. Preheat the kiln. Place four small kiln posts in the kiln, and preheat the kiln to 1780 F (971 C). Your kiln shelf should not be in the kiln during preheating. Place a large bucket of water on the floor by the kiln. Prepare the pickle. Fill a quart (1.4 L) slow cooker with water, add 10 oz. (296 ml) of pickle, and stir the mixture with copper tongs. Let the slow cooker start heating up. TIP: You can leave pickle solution in the slow cooker for future use. Turn off the slow cooker and leave the lid on when you re not using it. Add more water as needed to maintain the level of solution. Only use copper or wood tools in pickle, never steel. Set your piece on the kiln shelf. Cut a piece of fiber paper big enough for your piece, and lay the paper on the kiln shelf. The fiber paper will prevent your piece from sticking to the shelf. Lay your piece face down on the fiber paper. If the pearl wire extends above the piece, trim just enough wire that you can lay the piece face down. Fire the piece. Once the kiln is at temperature, put on a heat-resistant glove, and use long tweezers to pick up the kiln shelf and put it in the kiln, setting it on the kiln posts. Close the kiln door. Set a timer for 30 minutes. Quench the piece. When the timer goes off, pull the entire shelf out of the kiln. Tip the shelf so the piece slides off into the bucket of water [Photo]. Get the piece out of the kiln and into the water as quickly as possible; the longer the piece is exposed to the cooler air outside the kiln, the more the piece will oxidize. I tip the shelf rather than using tweezers to pick up the piece for two reasons: The tweezers will cool the piece faster, causing more oxidation; and, if I m firing multiple pieces, tipping the shelf gets all the pieces into the water in the least amount of time. Pickle and clean the piece. Put the piece in the pickle to remove any remaining traces of oxidation. It can take minutes to get it all to dissolve. When the surface appears red, rather than black, use a wire brush in soapy water to brush the piece. The dissolved oxidized layer will brush off easily. Rinse the piece. firing in carbon COPPRclay needs to be placed in a metal pan with activated carbon and fired in a brick kiln. I use a two-phase firing schedule to ensure that all binders are burned out and dissipated. The piece will shrink approximately 20%. Put the piece in a cold kiln on an open shelf. Fire the piece using a ramp speed of 500 F (260 C) per hour. Ramp to 560 F (293 C) and hold for 15 minutes. Open the kiln door and allow the piece to cool. At the end of this firing, the piece will be black and brittle. Handle it with care. Put about 1 in. (25.5 mm) of activated carbon in the bottom of a stainless steel pan. Place the piece near the back corner of the pan, about 1 in. (25.5 mm) from the edge. Do not place it at the front or middle of the pan, because very little heat reaches those points. Cover the piece with another 1 in. (25.5 mm) of carbon. Put the lid on the pan, and place it to the back of the kiln on kiln posts. Use the full ramp speed of your kiln to 1780 F (971 C). Hold for hours. Allow the piece to cool completely in the kiln with the door closed. I usually let it cool overnight. oh no! my wire came off! There are two ways your wire can detach from your fired piece. Either the wire itself breaks, or the wire remains intact but the piece of clay you used to attach the wire to the back lentil half comes off. Wires break for a few reasons. Your wire may be too thin. If you made your piece out of Art Clay Copper (ACC) and used 20-gauge (0.8 mm) wire, the wire will likely break; 20-gauge (0.8 mm) wire is too thin to stand up to the rigors of pickling. Use 18-gauge (1.0 mm) wire with ACC. You can use 20-gauge (0.8 mm) wire with COPPRclay and other carbon-fired clays, but never go finer than that. Another problem could be the wire s temper and quality; not all copper wire is created equal. Make sure you use 99.9% pure, dead-soft wire. I get my wire from a source that sells wire intended for jewelry making, not from the hardware store; wire intended for industrial use is usually an alloy. If your wire breaks, try drilling it out and using epoxy to set a new wire. If the whole attachment comes off, you didn t use enough material to reinforce the connection between the pearl wire and the back of the piece. (Three guesses how I learned this particular lesson?) Reattaching it with more paste and refiring doesn t work; it s epoxy to the rescue again. Clean both pieces with denatured alcohol, and reset the wire on the back lentil half, using two-part epoxy. You can eliminate the visible seam by coating the entire inside back of the piece with epoxy, from the outer edge to the wire. This will make the inside of the piece glossy and smooth, which looks nice with the pearl and hides the repair. 47

7 Part 4: Finishing From this point on, the instructions for all types of copper clay are the same. There are two ways to add patina to copper. You can use a chemical solution, like liver of sulfur, or you can use a torch. I chose liver of sulfur to get a dark patina. Brush the lentil. Use a wire brush in soapy water to brush the outside of the piece. Don t brush the inside; it s better to leave it unbrushed than to accidentally damage the pearl wire. Tumble-polish the lentil. Tumble the piece with steel shot and burnishing compound for 1 2 hours. Remove the piece from the tumbler and let it dry. Part 5: Setting the pearl Patinate the lentil. Prepare a liver of sulfur solution using very hot water according to the manufacturer s instructions. Use a wire to dip the piece in the solution until the piece is very dark. Rinse the piece and dry it well. Polish the lentil. Use a polishing cloth to vigorously rub the surface of the piece, bringing the highlights back to a bright copper color. The patina will remain in the recesses of the design. Use a soft cloth to buff the piece with a little Renaissance wax to help keep the copper from tarnishing so quickly. 1 2 Process photos by Pam East. materials Copper clay Copper wire: 16-gauge (1.3 mm): dead-soft, 1 in. (25.5 mm) For Art Clay Copper: 18-gauge (1.0 mm), dead-soft, 1 in. (25.5 mm) For COPPRclay: 20-gauge (0.8 mm), dead-soft, 1 in. (25.5 mm) 10 mm half-drilled button pearl additional tools & supplies Toothbrush Circle template Plastic Easter eggs Dust mask (optional) Sponge-tip makeup applicator Wire cutters Pliers: chainnose, roundnose Rubber clay shaper Micro mesh sanding swabs and pads Paintbrush: #4 flat Open-shelf firing supplies: long tweezers, Sparex pickle, small slow cooker, copper tongs, fiber paper, heat-resistant glove Liver of sulfur (patina gel) Polishing cloth Renaissance wax Two-part epoxy Diamond pearl reamer (optional) Denatured alcohol (optional) I like to use a slow-drying two-part epoxy for setting pearls. The type that comes in a two-barrel syringe works well and is available at hardware stores and many grocery stores. Look for one that indicates extended working time. Mix the epoxy. Once the wire is the correct length, mix the epoxy. Squeeze equal amounts of the two parts onto cardstock, and use a toothpick to mix them. You don t need to mix very much; a little bit goes a long way. Check the height and fit of the pearl wire. Set a 10 mm half-drilled button pearl on the pearl wire. If the wire is too thick for the hole in the pearl, use a diamond pearl reamer to enlarge the hole. Trim the wire to the correct height to hold the pearl [1]; the pearl should be at least halfway inside the piece but high enough that it appears to float in the opening. NOTE: When you trim the wire, work in small increments and check the pearl often. You can always trim off more, but you can t add wire if you trim too much. 48 Set the pearl. Use the toothpick to put a small drop of epoxy on the end of the wire. Push the pearl onto the wire [2]. Move the pearl up and down and twist it to distribute the epoxy, and then set it all the way down onto the wire. If you get any epoxy on the front of the pearl, clean it off quickly with a cotton swab dipped in denatured alcohol. Set the piece aside and allow the epoxy to cure for 24 hours. Applying epoxy resin across the interior of the back piece before setting the pearl makes it appear to float on water.