During my residency at Baltimore Clayworks in Baltimore, Maryland, I developed a body of functional porcelain work inspired by the bold, stylized, floral images found in traditional Japanese textiles. Rather than carving images directly onto the surfaces of my pots, I developed a technique in which large sprigs are applied to the surface and then carved, creating texture, dimension, and drama.
I throw or slip cast my basic forms, and then decorate them at the leather-hard stage using very thin press-molded sprigs. Using a single repeated sprig motif on each pot allows me to play with pattern, repetition, and rhythm, while also challenging me to continuously come up with new compositions using repeated images.
Creating a Sprig Mold
I create my sprig molds by carving Japanese-inspired line drawings of botanical images into leather-hard clay slabs. To begin, roll out a ½-inch-thick slab of non-groggy clay and dry it between layers of newspaper and drywall boards until leather hard.
Transfer your image to the slab by placing the print against the slab and tracing the image with a dull pencil (figure 1). Carve the image into the slab, varying the line quality and depth to create an active image (figure 2). Avoid carving lines that are more than 1⁄8 inch deep, as this may cause the pressed sprigs to tear.
Dry the sprig mold between layers of newspaper and drywall boards until bone dry, and then bisque fire it. Alternatively, you can cast a ½-inch-thick plaster slab and carve your image directly into the plaster. Be sure to wash away all plaster dust from the mold before using it with clay.
Throwing and Trimming
Using four to five pounds of clay, throw a low, wide 12-inch platter that has a shallow, continuous curve from the floor to the rim, leaving about a 3⁄8-inch-thick floor. Using a rib (I use a fan-shaped rib cut from an old gift card), scrape clay from the center of the floor to create an 8-inch-wide well. It’s important to remove enough clay so the well sits about 1⁄8-inch lower than the rest of the platter, as this will allow the final sprigged surface to be flush with the platter frame.
Create defining lines around the center well using the point of a wooden knife (figure 3). Use the knife to also define a line about 3⁄8 inch below the rim. These lines provide a guide for carving the platter frame, and help to keep glaze colors separate during the firing. Trim the foot when the platter is leather hard.
Rolling and Cutting Sprigs
Roll out an 1⁄8-inch-thick slab of porcelain. Store this slab on a plastic-covered ware board, and cover it with additional plastic so it doesn’t dry out. Cut a 4-inch square piece of the slab and roll it between pieces of smooth canvas or newspaper until it’s very thin, almost to the point of tearing. Alternatively, you can roll thin slabs using a pasta machine, but be sure to sandwich the clay between canvas strips so the clay doesn’t stick to the metal rollers.
Cover the thin slab with newspaper or smooth canvas and press the slab into your sprig mold with your fingers, just until you can see a faint outline of the image on the back of the clay (figure 4). Peel the pressed slab from the sprig mold (figure 5) and store it between plastic. Continue thinning slabs, pressing them into the mold and storing them in plastic until you have enough to cover the center of the platter.
Next, place one of the pressed slabs on a plastic bat and cut it out using an X-Acto knife (figure 6). Place the cut sprig back on the plastic-covered ware board and cover it with plastic immediately. Repeat with the remaining pressed slabs. If necessary, you can lightly mist the sprigs with water to keep them soft.
Applying the Sprigs
Layer the cut sprigs over the platter well, experimenting with placement to create an interesting composition. Pay attention to the shape of the negative space in the center of the platter. You can sprig the entire well of the platter to be flush with the platter frame, or leave a little window in the center for visual interest. Work quickly and lightly mist the sprigs if they’re getting too dry.
Once the sprigs are in place, lightly press near the edge of the center well so it shows through the sprigs (figure 7). Using an X-Acto knife, cut away the portion of each sprig that lies outside the well (figure 8). Using the overlap of the top sprig as a guide, cut through the sprig below and use the X-Acto knife to remove the excess sprig from underneath (figure 9). This allows the sprig pieces to fit together like puzzle pieces.
When all the sprigs have been cut to fit, lift one sprig up and brush a thin layer of thick porcelain slip onto the back (figure 10). Place the sprig onto the platter, being careful not to trap air bubbles beneath it. Repeat, going around the platter in one direction until all sprigs have been slipped and repositioned.
Carving and Refining
Carve radiating lines on the inside and outside frame of the platter using a rounded loop tool to create a fluted appearance (figure 11). When the applied sprigs are leather hard, use a small, pointed sgraffito tool to individualize and refine each petal. Begin by carving a line around the inside perimeter of each petal (figure 12), and then carve the interior lines in such a way as to mimic the natural curve of a petal. Concentrate on creating lines that have movement and rhythm to create an interesting image. Repeat with all sprigs. Brush off the clay bits as they dry with a soft, dry brush.
Dry the platter slowly to avoid cracking. Use a damp sponge to soften the cut edges of the carved lines on the platter frame when it becomes bone dry. Allow it to fully dry again before bisque firing.
I brush all of the glazes on my platters, using two or three different colors. To create brushable glazes, I decant a small amount of the glaze from my dipping bucket. To thicken the glaze, let it sit uncovered overnight. To make the glaze brush easily, add a couple drops of liquid glycerin, which is available from drugstores.
Brush two to three coats of a light-colored glaze onto the negative space at the center of the platter. Wipe any stray glaze off the sprigs with a damp sponge. Brush two to three coats of a darker-colored glaze on the sprigged area, and wipe any stray glaze from the platter frame. Brush two to three coats of a dark or black glaze on both the front and back of the platter frame (figure 13). Remove any stray black glaze from the other glazed areas by scraping it gently with an X-Acto knife. Clean off the foot ring as necessary. I don’t apply glaze to the inside of the foot ring to avoid sticking in the kiln, but you might be able to if your foot is tall enough. I fire all of my pieces to cone 10 in a gas kiln in reduction, starting the reduction around cone 012 to ensure a brilliant red color from the copper-red glaze I use.
Michelle Swafford was recently an artist in residence at Baltimore Clayworks in Baltimore, Maryland, and is now pursuing an MFA in ceramics at Tulane University in New Orleans, Louisiana. To see more of her work, visit www.michelleswafford.com.
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