The Ceramic Process

There are several steps in the ceramic process. I start with wedging, then I throw the piece and that is followed by trimming or assembling or both. After the piece is dry, I bisque fire to prepare it to be glazed. Once it is glazed, I fire it in the final firing and then it is complete.

I. Wedge

Wedging is the process of de-airing the clay. It is the same motion as kneading, except with the exact opposite purpose. When you are a wheel-thrower it is critical to work all of the air bubbles out of the clay. Centering is (theoretically) key in the throwing process and an air bubble will shift the piece off center as the wheel is spinning. I say theoretically because, hey, anything is possible if you put your mind to it.

II. Throw

Forming a piece on the wheel is known as throwing. Over the years several people have asked me why that is. A friend of mine ran across a wonderful article that will explains how, “The potter’s language has a core of words that go back to Old English roots”. This will answer many questions about the Verbiage of the Potter.

III. Trim/Assemble

Trimming is preformed when the piece is ‘leather hard’. I put the piece on the wheel upside down and attach it to the wheel head with wet clay. While the wheel is on I carve out the foot of the pot using trimming tools. To assemble my footed pieces I add a small triangular slab by scoring and adding slip as glue.

IV. Dry

All work must be ‘bone dry’ before it can be bisqued, otherwise the water in the clay could cause it to crack or explode. This is another theory that I have tested and it is not always true. I try not to risk it but sometimes time is not on my side.

V. Bisque Fire

I fire my bisque in an electric kiln. I fire to around 1600 or 1700 degrees Fahrenheit. This firing changes the clay chemically to a more rock-like substance. The main purpose is to make the piece porous like a sponge, and ready to accept the wet glaze.

VI. Glaze

Glazing is the process of applying the chemical composition that will both color the piece in the glaze firing and create a thin layer of glass on the piece. In the case of my work, the glass layer is what makes it food safe and able to hold liquid.

VII. Glaze Fire

I fire my work in a gas reduction kiln to about 2300 degrees Fahrenheit. A reduction environment is created by limiting the amount of oxygen at critical moments in the firing process. The purpose of reducing is to force the flame to search for oxygen to survive so that it will pull the oxides, such as iron oxide, out of the clay body and the glaze. In the case of iron oxide, it is forced out of the clay body or glaze and the fire burns off the oxygen and leaves a deposit of iron on the pot. Iron spotting contributes to the visual texture of the piece.

The entire process takes about 2 weeks. I schedule my glaze firings about 4 weeks apart and use the first 3 weeks to make enough product to fill the gas kiln. In my studio you can usually find work in each of the stages of the process.