BISQUE FIRING
After your work has dried to greenware the work is loaded into the kiln for the first of two firings. This firing is to approximately 1800 degrees F. This hardens the ware making it easier to handle without breaking during the glazing process. The bisque process is simply done to make glazing easier. The bisque firing takes a total of 3 days from start to finish. On day one, the kiln is loaded with the dry greenware and the kiln is lit, set at a low setting to dry the ware, and left overnight to slowly warm. Firing too fast during this early stage of the firing can easily cause the work to explode! On day two, the kiln is gradually turned higher and the temperature rises until the target temperature of 1800 degrees F. is reached. The kiln is then turned off and allowed to slowly cool. On day three, the kiln is opened, the bisqueware is removed. Your work is now ready to be glazed.
GLAZE FIRING
After glazing, your work has to be loading into the kiln again. The glaze firing process is also a three day affair. After the glaze firing temperature of 2350 degrees F. has been reached, the pots cool, and on day three, are unloaded. This is the final step in the process for the vast majority of pieces produced.
You cannot fire pottery clay in an oven because you cannot get high enough temperatures - but there are three options for DIY firing.