Drawing, Trailing, and Coloring: Creating Narrative Surfaces on Porcelain Heidi McKay Casto

Creating the Story 

In the days the pots are drying, I spend my time experimenting and exploring how to map out the drawings on each pot. I try to think through all the possibilities of what animals can take form on the surface, and how they might tell a story (1). 

Following the bisque firing, I sand each pot under water with 400-, 600-, and 800-grit wet/dry sandpaper to smooth the surface. 

Images onto the Blank Canvases 

Using the story map in my sketchbook as a guide, I draw on the pot with a cheap blue ballpoint pen (2). The blue helps to provide contrast from the black underglaze I will use for slip trailing. I use a pen instead of a pencil to avoid graphite dust mixing with the underglaze, which I find occasionally creates bubbles in the underglaze after firing. 

If too much time has passed between drawing on the pot with a pen and applying the underglaze, I re-wet the pot before applying the underglaze so that it is cold to the touch. This tiny bit of hydration helps the pot not be so thirsty for the underglaze, making it easier to lay a solid, steady line. 

Using a squeeze bottle, I then trace all the pen lines with black underglaze (3). If I make a mistake, I wait until just after the underglaze dries enough to lose its sheen and carefully scrape away the mistake with a sharp knife at a 45-degree angle, being cautious only to remove the black line and not damage the pot. 

Once all the imagery has been outlined, I treat the piece like a coloring book, filling in the blank spaces with colorful designs. I continue to use glaze in squeeze bottles for this step (4). 

Once I am satisfied with the design, I bisque the pots again. This vitrifies the design enough to stay put and burns out the pen marks, giving me a chance to see and fix the spots I may have missed. I put a liner glaze on the inside of the pots, leaving the outside free of any top glaze so the textures and details aren’t lost. 

Finishing Touches 

I do a final firing to cone 6 and then clean up any exposed porcelain with wet/dry sandpaper (5). When sanding, I first sand the bottom of my pots on the wheel with a 240-grit sanding bat, followed by 800-, 1000-, 1200-, 1500-, 2000-, 2500-, and 3000- grit wet/dry sandpaper, under water. 

Whether or not you use any of these skills in your own practice, I hope you take the time to exercise listening to your own instincts, especially in the studio. May your studio time be free of others’ expectations of what your work should be, allowing for more space for your unbiased creativity to take center stage. 

Heidi McKay Casto (she/her) is a ceramic artist and faculty member at The University of Iowa School of Art, Art History, and Design, where she is the Area Head of Ceramics. She earned her MA and MFA from the University of Iowa. Her work has been featured in over sixty group and four solo exhibitions. She was named a 2022 Ceramics Monthly Magazine Emerging Artist.