Inspired by cast glassware and vintage textiles, Colleen McCall decorates her stoneware pots from top to bottom using layers of porcelain slip, underglaze colors, and white, breaking tin glaze. She makes her patterns by taking motifs from various sources and combining them into her own unique designs.
In today’s post, an excerpt from the July/August 2015 issue of Pottery Making Illustrated, McCall explains her decorating process and includes tips for organizing source material and transferring designs to the clay surface. – Jennifer Poellot Harnetty, editor
PS. To learn how McCall appropriated a plastic carryout container to make this unique bowl form, see the July/August issue of Pottery Making Illustrated!
Learning how to Combine Patterns
My pattern book is sorted into five sections to organize the spatial dynamics of a particular pattern. Motifs such as animals or single flowers are the first section. A motif functions as a unit that can either be used alone as a focal point or can be repeated in various ways to create a pattern.
Section two, overall patterns, is most abundant since many fabrics are printed to be used in multiple directions. These patterns are random and don’t adhere to any one orientation. They work well on any shape.
The third section, vertical patterns, is limited in use to upright forms such as vases and mugs or square and rectangular shapes that have a top and a bottom. As an example, wallpaper tends to be vertically oriented.
What I call ground patterns, collected in the fourth section of my book, are those that are more basic and subdued. They act as a filler or create an interesting background when used with a focal point motif.
The fifth and final section contains borders or scrolling patterns that can trim a form or frame an overall design.
Jennifer Allen demonstrates similar decorating techniques in her video,
Darted & Decorated: Techniques for Enhancing Form and Surface.
Order your copy today!
When combining patterns I look for similar elements of shape, scale, and line. I can always unify patterns with complimentary color combinations. I also tend to mix styles and historical genres within a piece or in an arrangement of dishware, like bold Art Deco lines softened by an Ikat (a textile dying process) ground with Iznik pomegranates surrounded by calico. I draw each form once and photocopy it multiple times to play with dividing the form into zones for decorating. I can then play with adding patterns together. When I settle on a combination I may draw it once again and copy it multiple times to try color combinations (10).
I use paper stencils to transfer patterns to the form. Occasionally, I enlarge or reduce their scale to fit the form better. If your clay surface is a soft leather hard, I suggest putting a sheet of thin plastic between the clay and the paper template as the moisture from the clay will cause the paper to slough off into your precious line work. Trace the template with light pressure using a dull pencil or ball-tipped sgraffito tool. This leaves an impression of the pattern in the clay that guides your brush work (11).
When applying underglazes to create the patterns, I use wax resist thinned with water to paint more efficiently in layers. Apply wax over light areas of color to protect them when painting over with darker colors or to block the edges of motifs to make it easier to quickly fill in a solid background color. The peony and wheat pattern begins with hand painting the stamen and pink petals (12). The brown leaf dots are added with a fine-needled glaze applicator. When dry, the entire peony is brushed with wax resist. I give the wax about 20 minutes to harden before painting the background color (13). Using three coats of color provides a more saturated, solid color. Using a graphite pencil, I then sketch the stem of the wheat in alternating directions throughout the ground. I paint the wheat kernels last in a slightly darker color than the chartreuse. Any time I incorporate a transparent glaze color into the motif, it lessens the painting time but also adds a new dimension to the design.
My favorite sgraffito tool is a tight cornered ribbon tool. I find it grabs the clay more surely, allowing me to vary the pressure, which alters the line thickness (14). I also keep a variety of sgraffito tools on hand depending on the line quality I prefer. Tip: Depending on the form, you may want to work from left to right if right handed or from the middle out to keep from smudging newly drawn lines. As you begin to carve through the layers of slip, underglaze, and wax, the remains will pile up. Simply dump them out into your glaze and clay recycle bin and continue carving. Don’t brush or blow them off as they may mar the surface and create excess dust. Brush off any straggling bits of clay after the bisque firing when the work is wet sanded.
Wet Sanding Bisqueware
Wet sanding bisqueware removes sharp burrs created by carved sgraffito lines. To wet sand bisqueware, use lots of water to keep the dust to a minimum. I work over a bowl of water with 320-grit wet/dry sandpaper alternating between sanding and sponging to remove dust from the sgraffito crevices (15). Be careful not to sand off the underglaze color. Mistakes can be easily fixed by applying more underglaze to the thoroughly cleaned bisque. Caution: Always wear a dust mask when doing any sanding.
The first stage of glazing on the peony and wheat pattern is to apply a transparent celadon green glaze to the leaf and stems of the peonies with either a brush or glaze applicator squeeze bottle (16). Finally, the entire interior is brush coated with two thin layers of transparent clear glaze (17).
Colleen McCall is a full-time studio artist living and working in Elmira, New York. To see more of her work, visit www.colleenmccallceramics.com or visit the Upstate New York Ceramics Invitational at Main Street Arts (www.mainstreetartgallery.com) in Clifton Springs, New York July 11–August 30.