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When I was an undergraduate ceramics student, I learned to throw something called a yo-yo pot. It’s a straight-walled cylinder, that is collared in at the top until completely closed. After leveling the top of the enclosed form, an indent is made around the side wall. Once the clay becomes leather hard, a needle tool is used to cut through the clay wall at the bottom of the indent. The top section is now a lid, and the indent becomes the lid seating or flange that fits into the bottom cylinder, making it a jar. Right after throwing it, the indent causes the cylinder to look like a lopsided yo-yo. This simple pot is one I’ve consistently made throughout my years in clay. Not only is it fun to throw, but it’s also a great teaching form as it contains several different pottery techniques.

 

This past year I’ve been inspired by several artists making flower bricks and found this yo-yo pot design easily transformed from a lidded jar to a flower brick with a removable top. The flat, smooth surface is a perfect canvas for a colored slip and sgraffito carving.

1 Throw a straight cylinder, then alternate collaring and pulling the top third. 2 Continue to alternate collaring and pulling to narrow the top of the cylinder.

Throwing the Enclosed Form

Begin by throwing a straight, even-walled cylinder on a bat using 1–1½ pounds of clay. Collar in the cylinder by gently constricting the clay starting about one-third of the way down from the top (1). Alternate collaring and pulling to form a small chimney (2) that is then narrowed (3) and pinched off, closing the cylinder. Once the top is sealed, use a stiff rib to straighten the side wall (4), then smooth the dome top with a softer, more flexible rib (5). The enclosed form creates an air pocket that allows more pressure to be applied when shaping, and prevents the lid from collapsing.

Creating the Lid

With the wheel at medium speed, create the groove that will become the lid seat by pushing the end of a craft stick or rounded edge of a pottery knife into the clay at a 45° angle (6). Rock the tool back and forth from its top to bottom edge to evenly move the clay inward. The groove should be roughly ¼–⅓ inch wide. After setting the indent, straighten the walls using a firm rib.

3 Close the top and pinch off excess clay from the final narrowing motions. 4 Use a firm, straight-sided rib to straighten the side walls. 5 Use a flexible rib to create a smooth, domed top. 6 As the wheel is turning, create a groove that will become the lid seat.

Use the sharp corner of a stiff rib to make an accent line on the top, about ½–1 inch from the edge (7). This adds a frame around the top of the lid. Next, use a wooden knife to remove any excess clay from the bottom edge, then trim a slight undercut. Wait to cut the thrown form off the bat until after the lid is cut to prevent distortion that will make it hard for the lid to fit properly.

Finally, poke a small air hole at the bottom of the indented groove using a needle tool to prevent the cylinder from swelling due to trapped air as it shrinks while firming up to leather hard.

7 Use the sharp, 90° edge of a firm rib to make an accent line on the top of the lid. 8 Once leather hard, use a needle tool at the base of the groove to cut the lid free.

Trimming the Lid

When the pot is leather hard (firm enough to hold its shape, but soft enough that it can still be cut), it’s time to cut the lid from the body of the pot. While the wheel is slowly spinning, use a needle tool to cut through the bottom edge of the groove (8). Keep one hand on the lid so that when it’s cut free, it doesn’t fly onto the floor (9). Set it aside and trim any roughness from the top edge of the newly cut cylinder.

Flip the cut lid upside down and center it on top of the cylinder, which works well as a chuck (10). Trim the edge of the lid seat to remove the rough clay. Turn the lid over and place it back onto the body of the pot. If it doesn’t fit, continue to trim clay from the lid or cylinder edges until it fits snugly onto the cylinder. When the lid is finished, cut the cylinder off the bat and refine the bottom edge by rolling it on a table or using a finger to create a smooth, slightly beveled  corner.

9 Hold the lid while cutting so it doesn’t fly off. Lift the lid from the cylinder. 10 Trim the top of cylinder, then use it as a chuck to trim the upside-down lid. 11 Brush a layer of Class Black Slip over the edge of the lid and body. 12 Use wire loop tools and triangular wire tools to carve designs.

Sgraffito Design

13 Use the round end of a trimming tool to make circular divots around the lid rim. I brush a layer of Class Black Slip (see recipe) over the edge of the leather-hard lid and body (11). The slip should be the consistency of heavy cream. If it doesn’t brush smoothly onto the pot, dip the brush into a little water to help it glide over the surface.

After the slip is set and no longer tacky to the touch, plan the design to be carved. Recently I’ve been exploring floral patterns that travel around the vessel. Start by using a wire loop tool to carve the main flowers (12). Once the main outline is carved, move to a larger sgraffito tool with a triangular head. Use this tool to remove the slip around the design and create texture in the negative space. Leave hints of the slip between swipes to add depth once the piece is glazed. This also creates a foreground and background. The surface design is finished by putting a border of circles around the lid using the round end of a trimming tool (13).

Finally, measure and cut strips through the top of the lid (14). Feel free to be creative and design your own pattern of cutouts on the top; I like to encourage students to adapt ideas and make them their own.

14 Measure and cut strips of clay out of the top of the lid. 15 Pour a liner glaze inside the pot, then dip the exterior.

Carved flower vessel, 4 in. (10 cm) in height, wheel-thrown stoneware, fired to cone 6 in reduction in a gas kiln, 2020.

Sanding, Waxing, and Glazing

Once the pot is bisque fired, use 100-grit sandpaper to smooth away any rough edges left from the carving process. Caution: Do any sanding outside or in a well-ventilated area while wearing a professionally fitted respirator.

Prepare the pot to be glazed. Clean all dust particles from the surface and brush wax resist on the lid seat. I use Satin Spodumene, a white matte glaze (see recipe), which highlights the texture from the carved areas and becomes gray over the parts with black slip.

Pour glaze into the interior of the pot using a cup while simultaneously rotating the pot to completely cover the interior, then pour the glaze out (15).

Holding the pot by its base, dip it straight down into the glaze to coat the exterior. Dip the lid last. After cleaning off glaze residue from the waxed lid seat, place the lid onto the pot and fire it to cone 6 in reduction in a gas kiln.

All process photos: Nathan Campbell.

Dodie Campbell is the studio assistant and a wheel-throwing instructor at the Sawtooth School for Visual Art in Winston-Salem, North Carolina. She can be found on Instagram @dodieac.

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