A natural progression of any art, once your skills are refined, is seeing how BIG you can go. This is particularly true in ceramics. Larger is not necessarily better, but often a great way to push yourself and see how well you’ve mastered the basic mechanics of throwing. Throwing larger vessels is really no different than throwing smaller ones. The basic mechanics are the same, only a few simple adjustments are needed to compensate for the larger amount of clay.
The first and most obvious step – start with a lot of clay. You can’t make large vessels without large quantities of your material. Keep in mind that you will lose a bit of clay during the process, even more if this is your first time going big.
The larger and taller your piece is, the thicker the walls need to be. A 2 foot tall pot may need walls that are over a half inch thick (depending on the clay body) to support its own weight. In the picture above I have 25 lbs of clay on the wheel.
No, I did not wedge one 25 lb mass of clay. Instead I wedged up two 12-and-a-half pound balls and put them on the wheel one on top of the other. I then patted them together while slowly spinning the wheel. As you pat the clay down try to pat it as centered as possible, this will make centering the clay significantly easier. When centering these amounts of clay, it’s important to put your whole body weight into it, sometimes standing up and leaning into it will help. All the same principals of centering still apply: make sure you are compressing the clay at the proper angle from the side and compacting the clay downwards from the top. Because the mound is so much larger, you may have to move your hand up and down or use two hands on the side to get enough of a push.
Pulling the clay has, again, all the same principles. Compress the clay at 5 o’clock and slowly pull up. This of course is much easier said than done. Make sure your body is braced and your arms tucked in tight. For the first few pulls, when I’m moving the most amount of clay, I like to use one of those large yellow clean up sponges as my outside hand. I make a fist with the sponge covering my knuckles and then push that against the outside. This gives a much sturdier compression against the clay and the sponge allows for a smooth transition. Don’t try to pull it all up at once! Think of your first pull as a centering pull. Move the clay up a little but mostly move the clay into a good position for your next pull. Keep your base thick, the base of your pot is what’s holding all the clay up, if this thins out too quickly you’ll get torquing or it will flop in on itself.
In the picture above you’ll see a fan blowing on the piece while I’m working on it. This is key. A torch is also a helpful tool for making larger pieces. Because so much of your hands is touching the surface of the clay, you’ll need to be using a significant amount of water. When the walls of your piece get over saturated it will start to slump back into itself. After a pull or two use your metal rib to scrape the slip off the surface, then let the piece spin in front of the fan for 10 minutes or so. This allows the piece to dry out a bit between pulls and allow you to have thinner walls without it slumping in.
Shaping large forms can be tricky. Sometimes different tools are needed to get a desired shape. Many potters make their own tools as they progress in their work. Before you begin to shape your piece let it spin in front of the fan for 20-40 min. Allow it to dry out some and stiffen up, this will keep your form’s shape much tighter and allow you to stretch the clay further. Keep in mind that when you open up a form into a more bulbous shape, you’re going to lose some height, several inches in fact, depending on how wide it is. When stretching the clay outwards be sure to come back on the outside and compress the clay with a metal rib. This will keep your form nice and tight. While shaping the piece keep the base nice and thick, this will help keep your form balanced while you push and stretch the clay. The base can always be trimmed off with a fettering knife, this is one of the last steps before you allow the piece to begin to dry.
Finish off your work and cut away any excess clay at the base. This could be done when it’s leather hard – utilizing trimming tools. To allow the piece to dry to that state more evenly, it is important to trim away as much as you can. Wrapping the rim in plastic is another alternative.
Now take your big piece home, show it off to everyone you know, and bask in the Texas-sized praise.
For more throwing large action, check out this tutorial video “How to Throw Large Forms on the Wheel.”