One of the biggest challenges when learning to throw is often getting the clay at the base of the pot up into the form. Not overcoming this challenge results in tons of clay to trim off in the trimming stage and/or a clunky heavy pot.
With pitchers, this heaviness can be a real problem because they are meant to carry a large volume of liquid. Glenn Woods came up with a way of avoiding this extra clay at the bottom, which resulted in a more graceful form and a lighter pitcher. He shares this technique in today’s post.- Jennifer Poellot Harnetty, editor.
Several years ago, at an art fair in Florida, I encountered another potter who came into my booth and said, “I really like your pots but they seem to be missing the bottom part of the form.” At first I was offended—who did he think he was anyway? His forms didn’t seem any more spectacular than mine. After I got over myself, I looked at my pots and found he was right. I love to throw but have always noticed that no matter what pulling method I have used, I always seem to leave a little more clay at the bottom of the wall than I would like. I also noticed that the pots did seem to be lacking a little toward the bottom part of the forms. After thinking about this, I decided that I needed to find an easier way to use the clay left at the bottom of the piece rather than simply carving or trimming it away and discarding that clay into to my reclaim bucket.
If you’re looking for a way to really spruce up the surface of your pots, check out Meredith Host’s video! In addition to great throwing demonstrations in porcelain, Meredith leads you step-by-step through the entire underglaze decorating process using stencils and screens and lots of color. If your pots have been looking a little bland, now’s your chance to really make your surfaces stand out.
With the next piece, I threw the vase the way I always have but left a little more clay in the floor of the piece (a thicker bottom). I then wrapped the bottom of the piece in plastic to keep it wet and let the top dry to leather hard (figure 1). Since I hadn’t altered the piece, it was easy to turn upside down and center on the wheel just as if I was going to trim the piece (figure 2). I trimmed away the flange from the bottom, leaving the edge beveled toward the center (figure 3).
Rather than trimming any more clay away, I cut a hole in the center of the bottom of the piece and pulled the bottom out toward me, just like opening up a ball of clay before starting to throw a cylinder. Once the bottom was opened, I applied slip only where needed and began pulling and thinning the walls where I would normally be trimming away extra clay (figure 4). Once the wall was a uniform thickness, I collared in the form and continued thinning. This process added an additional 3 to 5 inches to the overall height of the piece and enabled me to create a more pleasing form (figure 5).
To close the bottom, I simply threw a clay pad, compressed it, and then added a throwing ring so that when a person looks insidethe pot, they see a beautiful spiral staring right back at them. I scored the bottom edge of the pot (figure 6) and marked the clay disc (figure 7) with the diameter of the foot, scored just inside this line, then attached them while the clay pad was still on the bat. Next, I compressed the seam (figure 8), cut away the excess clay and beveled the bottom (figure 9), then cut it off the bat.
I set the pot on a plaster dome to make the bottom concave. The plaster also helped to even out the moisture in the bottom quickly so I didn’t end up with stress cracks. Once it dried to soft leather hard, I set the piece on a level table to make sure the bottom edge was even all the way around and the piece was level.