Ecology, landscape, and our evolving relationship with the natural world have always been themes I’ve explored in my work. With my illustrated wall plates, I try to capture the beauty and energy of the cycle of growth, reproduction, decay, and regeneration in the garden. Drawing inspiration from plants, insects, fungi, and microorganisms in soil, I aim to recreate a world that is dynamic, strange, and beautiful. I use the glazing technique of cuerda seca, which involves painting lines on the bisque piece in a mixture of wax and iron oxide, then glazing the spaces in between to create the imagery.
Making the Plates
The plates are formed on a plaster hump mold that was made intentionally bumpy and slightly irregular as a foil for the tightness that’s inherent in the cuerda-seca technique. A circular slab approximately 22 inches in diameter and 5/8 inch thick is placed onto the mold and beaten down with my hands to produce an exterior surface similar to the interior of the plate. A thick foot ring is then added while the slab is still on the mold. The outer 3 inches of the slab are covered in plastic to keep them moist while the rest of the plate is left to dry to the leather-hard stage before it’s taken off the mold. After removing the plate from the mold, the rim is pinched to raise the walls up a couple of inches. The rim is cut level with a fettling knife and then lightly pinched again to create a sharp edge. A rib is used to compress the outer wall in order to form a slightly inward curved rim. This creates an enclosed frame in which to contain the imagery. The plate is then bisque fired to cone 06 in an electric kiln.
I start the surface decoration on each piece by drawing directly on the bisque-fired plate in pencil, roughing out the overall design. Though every design is unique, I’ve developed an extensive vocabulary of stylized imagery (1) to be used in various configurations.
The excitement for me is in creating asymmetrically balanced but active compositions. I use rough paper cutouts to help plot the composition (2). These cutouts have the advantage of letting me see the shape, placement, and directional movement within the composition before committing to drawing it in place. As I plot out the drawing, I think ahead to how it will be glazed using the dozens of glaze colors and textures I’ve made for this purpose.
When I’m happy with my drawing, I apply the cuerda-seca wax-resist lines with a liner brush (3). The pencil drawing serves as a rough guide. As the wax lines are put down, make small adjustments so there aren’t many lines converging or overlapping in a tight space. Keep in mind that the process creates outlined glaze shapes. What looks good as a line drawing doesn’t always translate well in glaze. Too many converging lines create a patch of dry black clay with tiny bits of glaze in the unwaxed areas.
After completing the wax lines, set the piece aside to dry (4). Usually an hour is sufficient, but it shouldn’t be left for more than a couple of days as the wax and oxide mixture becomes less effective as a resist, making the glazing process slower.
Apply the glazes with a soft brush, loading up the brush and jiggling it over the area to be glazed (5). The glaze flows off the brush into the space and is contained by the wax lines. Slip trailers and squeeze bottles (6) work well when applying glazes on flat surfaces (e.g. tiles), but can be tricky to use on curved forms. The glaze goes on thick and pools within the wax lines on a horizontal surface, but will flow over the lines on any curved surface. The brush is handy for keeping the glaze in place until it sets up. I add 0.5% CMC Gum (dry weight) to my glazes to extend the drying time, which allows me to brush on the glazes evenly.
Usually each outlined section is filled in with a single glaze (7), but occasionally two or three blended glazes can be used for textural or modeling effects (see 10). One of the benefits of separating the glazes within a wax line is that different types of glaze can be used side by side. Because the glazes don’t overlap, no eutectics are formed, and problems such as running or bubbling are avoided.
When the glazing is finished, inspect the wax outlines, and use a dull pencil to scrape back any glaze that has overlapped the line. Finally, I glaze the back of the plate with a soft-flowing matte glaze of a single color (8). The work is then fired in an electric kiln to cone 2 using a 10-hour firing schedule.
Tips on Glazing and Firing
Any stiff glaze that doesn’t flow or run when melted can be used. Cuerda seca can be used at all temperatures, but looks best in the lower firing temperature ranges. I fire to cone 2 and make all my own glazes for this temperature. If using commercial glazes, you’ll have to do some testing.
I use matte, gloss, and textured glazes in dozens of colors (9). By treating some shapes as flat space and others as implied volumetric forms, I play with a sense of depth that shifts between 3-D illusion and flat pattern (10).
Marc Egan studied ceramics at Sheridan College School of Craft and Design, Oakville, Ontario, Canada. He currently works in his Toronto studio producing pottery and ceramic sculpture. Egan teaches in the ceramics department at Sheridan College and at the Gardiner Museum in Toronto. He also leads workshops in ceramic surface design and glaze chemistry. His work is in numerous private collections as well as the collections of the Canadian Clay and Glass Gallery, Waterloo, Ontario, and the Gardiner Museum and the Royal Ontario Museum in Toronto.