One of the greatest things about clay is its ability to take on texture. Another great clay quality is its malleability and stretchiness. Combine those two and you can really create fun surfaces!
In today’s post, an excerpt from the July/August 2021 issue of Pottery Making Illustrated, Elizabeth Paley demonstrates how she uses slip, a pastry wheel, and clay’s stretchy nature to create fabulous surface texture. – Jennifer Poellot Harnetty, editor.
PS. For more variations on this technique (including a crackled effect made with sodium silicate), plus tips on refining your textured and stretched pot, check out the July/August 2021 issue of Pottery Making Illustrated!
Compress the exterior of the cylinder with a rib to remove any remaining water or throwing slip, and to ensure the wall is flat and smooth. With the wheel spinning, apply a thin layer of contrasting slip to the cylinder, using your fingers or a wide paintbrush. The slip should be viscous enough not to slide down the wall. Leave the top inch of the cylinder unslipped; later, you will shape this section into the neck.
Pastry wheel: Stop the pottery wheel. Starting at the base of the cylinder, roll the pastry wheel vertically up the wall of the pot, stopping where the slip ends. With minimal pressure, the pastry wheel should cut through the slip into the clay. Repeat this process, creating vertical lines around the entire cylinder (1). Pause as needed to clean accumulated slip off the pastry wheel using a toothbrush. Tip: Do this away from the pottery wheel to avoid splattering the pot (although splatters can be gently scraped off later with a loop tool or utility blade once the vessel is bone dry). Dry off the pastry wheel and check that it spins freely before continuing to texture the cylinder.
Stretch the Pot
Use a sponge to remove any lines that were cut into the unslipped portions of the wall (2). With the wheel spinning at a moderate speed, use the curved edge of a rib (any curved rib that fits into the pot will work for this, just avoid ones with pointy tips) to gradually stretch the wall outward from the inside; this will require several passes (3–5). Take advantage of the curves of different ribs to shape the curve of the pot.
I usually begin stretching my pots from the top down rather than the bottom up; I find it easier to keep the top centered this way, and I’m less likely to stretch the bottom farther out than intended. (Once the clay has been pushed out, it cannot be pushed back in without damaging the exterior design.)
To keep the pot from collapsing as it is stretched, use your outside hand to aim the heat gun at the clay, continuously moving the tip up and down to avoid over drying any particular portion of the wall (6). Use the heat gun only as needed to stiffen the wall: over drying makes the clay harder to stretch and can lead to rips, cracks, or bulges. Stretch until you are satisfied with the form (7).