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 David Schlapobersky and Felicity Potter are leading South African studio potters who have been working together in the tradition of high-fire, reduction stoneware and porcelain since 1973. Their open, working pottery studio is in the historic heart of Swellendam in the Overberg region of the Western Cape, South Africa.

They work in collaboration, with David taking care of preparing the clay, making pots and blending glazes, while Felicity decorates the work prior to glaze firing in one of two oil-fired kilns.

They make a wide range of items including functional and decorative stoneware and porcelain, as well as large floor jars, urns, platters, fountains, garden and indoor containers.

David has developed a process that combines throwing and adding coils to create pieces up to four or five feet in height. He demonstrates his method for making a tall vase here.

Process

Center 15 pounds of clay (figure 1). If it’s too difficult to center that much at one time, try centering five pounds of it at a time, one over the other, starting at the bottom. Open up the clay to within ½ inch of the wheelhead (figure 2). To ensure the base is properly worked down and compacted, David adds a small flat piece of clay on the base, which he works in to release any trapped air and compresses by pressing down firmly (figure 3).

Next, open out the form to about 8 inches and begin to pull the clay up to form thick walls that taper inward (figure 4). This also gives you a thickish rim. Repeat the process, this time adjust the pressure and your hand position so that the cylinder has straight walls (figure 5). Pull the cylinder to the final height and flare outward to form the desired shape, about 12 inches in diameter at the top. With a kidney rib, bevel the top slightly outward to accommodate the angle of the next step, which continues the outward curve (figure 6).

You are now ready to quick dry the pot to stiffen the walls before doing any further work. First, run a wire tool under the base of the form to release it from the bat. This quick drying step creates sudden and uneven pressures that could cause the foot of the form to crack if it is left attached to the bat. Dampen the throwing bat to prevent it from burning. Using a blow torch, and with the wheel revolving at your throwing speed, dry the pot (figure 7). First heat the outside, then the inside. After a minute or two, repeat the drying process. The clay will start to change color, and become leather hard.

After two cycles of using the blow torch, the pot should be firm enough to handle about 10 more pounds of clay. Roll out an 8 or 9 pound coil. Since your pot is about 12 inches in diameter, you’ll need a 36 inch coil. Score and dampen the top of the pot then place the coil on the rim. Cut and join the two ends together (figure 8), place the coil onto the pot, but do not fix it to the rim at this point.

Press the coil down and inward with the wheel revolving slowly, so that the outside of the coil is flush with the pot and the roll is overhanging on the inside. Now you are ready to throw again to thin out this added coil and shape the contour to make its transition with the pot seamless.

Throw by pulling the inside roll up, with the wheel spinning at a slightly slower speed than when throwing the pot. Shape and trim off any uneven clay. Once again, compress the rim and prepare it for the next coil.

Clean the outside join and address the transition if necessary. Remove the excess clay from the inside join using a sharp trimming tool or rib, and clean out any slurry from the bottom of the pot (figure 9). Note: When you finish throwing the coil, the top flare should be a little exaggerated to allow for quick drying.

Dry the pot as before, using the blow torch (figure 7). You may need to wet the upper part of the first section prior to heating the piece, so it does not dry out too much. Clean up and remove any small dried edges on the rim.

Now add a slightly thinner coil (about 36 inches in length) made from about 5 pounds of clay (figure 10). Repeat the process of attaching and throwing the coil as before. This second coil should give you enough clay to form the widest part of the pot and start to curve the form back in, finishing up to the shoulder of the pot (figure 11). Clean up and dry the pot as before. Note that the bevel at the top edge should slope gently inwards for the final coil, which will become the rim of the pot.

Glazing David and Felicity usually skip the bisque fire, but their glazing technique is the same for greenware or bisqueware. After spraying the entire pot with a glaze, they add brushwork decoration using various oxides and pigments. After thoroughly drying the pots, the work is fired to cone 12 in a gas kiln in a reducing atmosphere.

Glazing
David and Felicity usually skip the bisque fire, but their glazing technique is the same for greenware or bisqueware. After spraying the entire pot with a glaze, they add brushwork decoration using various oxides and pigments. After thoroughly drying the pots, the work is fired to cone 12 in a gas kiln in a reducing atmosphere.

Add a final coil, rolled out from about 2 to 3 pounds of clay. Throw the desired neck and rim (figure 12) and clean up the inside of the pot and the transition as before. The final coil allows for a bit of creativity. You can finish off these tall forms as vases, jars, or bottles. Dry as before and add accents like lugs, handles and or sprigs. Your final pot will be around 28 to 30 inches tall. 

Michael Guassardo is a professional potter and the editor of National Ceramics Quarterly. He lives and works in Knysna, South Africa. For comments, contact him at editor.ncq@webafrica.org.za.

David Schlapobersky and Felicity Potter operate the Bukkenburg Pottery Studio & Guest Cottage in Swellendam, South Africa. For comments or questions, contact them at bukkenburg@sdm.dorea.co.za or visit their website at www.pottery.co.za.

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