Making Pots and Throwing
Now that we've talked about this stuff we call clay, let's talk
about what we're going to do with it. When we make a pot on the
potter's wheel we use a term called throwing. Ceramic scholars tend to
agree that this term probably came from the first action of the potter
at the wheel, actually throwing the clay ball down onto the wheel head.
There is another theory, that "to throw" in Latin is actually "to turn",
having to do with the turning of the potter's wheel, a revolutionary
idea if there ever was one!
There are two main shapes that wheel
thrown pots are made from - the cylinder and the bowl. In the first
six-week session at Hands In Clay, our main emphasis will be on the centering
of the clay and forming of the cylinder. With the cylinder we focus on
the seemingly Herculean task of getting the clay "up" and our goal will
be that wonderful pot of our morning ritual - the coffee mug.
There
are very few operations that look so simple yet which in fact are so
difficult to master as throwing. Once learned, however it in not easily
forgotten and soon it becomes a skill which is completely absorbing,
fascinating, and satisfying.
7 STEPS OF THROWING
Wedging
Centering
Opening up
Compressing
Pulling
Forming
Finishing
Common Problems in Throwing
Clay that is too stiff, too soft, or poorly wedged.
Opening up the clay before it is properly centered.
Greater pressure with one thumb than the other when opening the ball, making the walls uneven.
Applying too much water so that the clay becomes to soft.
Unsteady pressure from inside the pot, making the pot wobble.
Pressure from both the inside and the outside fingers, causing the thin or weak spot in the wall.
Throwing too slowly and overworking the clay, causing the pot to sag.
Allowing throwing water to collect in the bottom of the pot, making the
clay soft and unable to hold its shape when removing. This also
creates a tendency for the dreaded S-crack.
The S-crack
can be avoided by removing throwing water with a sponge, by compressing
the bottom of the pot to make a smooth even bottom, by drying slowly,
and also by trimming with a firm downward pressure.