Glazing and Firing Big Pots
The initial firing is known as a bisque, and I heat it to 1000 Degrees Celsius. In the large kiln, this process takes 3 days to gradually increase in temperature and then cool down enough to be opened.
If I were to fire the bisque too quickly, any remaining moisture in the clay would convert to steam and cause the clay to explode. This can still occur today (even if I ought to know better after 30+ years) if there's a rush and the environment is cold and damp.
Before firing starts it is difficult to move the pieces and load the kiln, so sometimes my husband comes to help, to transfer sculptures from the making area into the kiln.
The second firing goes to stoneware 1250 Degrees Celcius which renders the material frost-proof, when the space between clay particles shrinks and water can not enter and expand when it turns to ice.
I paint on a white shiny glaze that will give a bright background to the colourful glazes applied before the last firing. More about that in the next post.
It will take 9 days to fire 1 big sculpture 3 times and another two days for the glaze applications.
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