The making of pottery - pots on fire!

Proper ventilation prevents glaze defects.

Since my kiln is in the midst of a glaze firing, I figured I'd take the oportunity to share with you some of the process of firing your pieces. In future blogs I'll share many subjects on how to make pottery. But for now let's just focus on the firing process.

There are a few ways that firings can differ from one another. When most people think of firings they often envision a huge kiln, with smoke coming out the top, cooking the pots for days on end. While this is an ancient method of firing (wood burning) it is not the method used by the majority of potters at this time. Sometimes people think of red hot pots being taken out of a kiln and placed into barrels of combustable materials. This also is a well known technique for firing. It is called Raku and named after a Japanese family that developed tea ware for traditional Japanese tea ceremonies. There are also gas-burning kilns and electric kilns, even pit firings. Using an electric kiln is more common as it provides more predictable results. This is what I use.

slowly getting hotter!

Today I am doing the second firing on the wares. It is the glaze firing. The first firing is at a lower temperature, typically between 1648-1940 degrees F, and is called a bisque firing. During the bisque firing, clay that is bone dry, is very slowly heated up to evaporate moisture and eliminate physical and chemically bonded water. If done incorrectly the results can be explosive, so care is needed. In the end the result is pottery that is harder, less fragile and ready to glaze.

After applying glaze and letting it dry completely we do a glaze-firing. This is what I am doing right now. Glaze-firing temperatures can be as low as bisque-firing or as high as 2516 degrees F. Your pots will reach a temperature between 2165-2185 degrees F. Truly "hot pots"! These very high temperatures cause the clay and glaze to vitrify becoming fused at the particulate level. Most pottery is glaze-fired only once, although I often refire two to three times to achieve the desired effect. Again, the pots are susceptible to damage, such as exploding, warping, fusing to the shelf, forming blisters and any number of glaze deffects during this firing so great care is needed. As all potters do, I've learned a great deal thru trial and error. No pot lost is truly a loss since there is always a lesson learned.

Hot Pots!

Well, that's a basic run thru of how firings work. When you get your pottery and as you enjoy it remember that, that little pot went thru a great deal to make it to you! Enjoy!