June 19, 2009

Fire Away!

Today I woke up to find that everything I had hoped would be bone dry by morning in fact was, so I just closed the lid on this next bisque load and fired up the kiln. There are a few shelves stacked beneath this one with more bowls and stakes and some bud vases, I think. Funny, I must have a version of kiln load amnesia…once I pack it, I forget what I’ve put in there.

Clay work is time consuming. I think what most people don’t realize is that drying the finished piece from its wet, plastic stage to sufficiently bone dry for bisque firing takes a long, loooong time. For smaller pieces like my tiny bowls, I can sit them in front of a fan to speed up the process with no ill effects, but for flat pieces and larger pieces especially, drying must take place slowly under plastic covering and over the course of several days to prevent warping. This is because the water content of the clay is evaporating and bringing the clay particles themselves closer to each other in the process. If a piece is exposed to air and dried rapidly, the clay particles align quicker on the top than they do on the bottom and this is what causes the warping. In some cases the warping only shows up after the bisque firing (surprise!), so I’ve learned to be very careful and patient during the drying stage.

Next, adding color glazes. Stay tuned!

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