When I came in this morning the kiln was at 1,006 deg. F. I set our ultimate target temperature of 2350 deg. F, which is cone 10. At about 1:00pm I began a body reduction, and continued it through cone 010-04. When reducing a kiln, you are basically diminishing the oxygen supply. When cone 04 dropped I set the kiln to a neutral environment, indicated by a green flame - which is neither a reduction or oxidation atmosphere. I fired the kiln in this neutral atmosphere for about 5 more hours, checking every half hour to record the temperature climb and check the cone packs, as well as making sure the atmosphere was unchanged. When cone nine was going down (at about 2280 deg F) I began the glaze reducation, once again cutting off the oxygen supply. It is somewhat difficult to maintain a true reduction while reaching temperature at this point; because of the lack of oxygen, the temperature can stall, or drop all together. There is quite a bit of tinkering that one must do, including adjusting the damper, air flaps, fan speed, and gas pressure. I allowed the kiln to fire in reduction for a bit more than a half hour, and after cone 10 dropped (at 2300 according to the pyrometer, which is not exact), brought the kiln into a short oxidation period to encourage the development of bright colors in certain glazes, and finally shut off the power and gas at 7:00 pm.
While Firing the kiln, I was working on several different projects. I began by unloading a bisque kiln of student work. I am the teachers assistant of a ceramic handbuilding class, and one of my responsibilities - apart from mixing materials, creating handouts, preparing demos, and advising students on process and concept, - is loading, firing and unloading class work. Once finished I headed to the plaster room to check on one of the two molds I poured the night before. [For my next project I will be casting three different clock forms and creating a sculpture to communicate the pressures of time.] I destructed the coddle boards, and lifted the press mold from the clock and clay slab, with a good amount of difficulty due to the size of the clock and consequently the plaster mold. Once the prototype was removed, I washed the excess clay and mold soap away, and set the mold to dry in front of a fan.
Moving on to my next project, I wedged two large portions of porcelain, and set them through the slab roller, rolling each to a thickness of 1/8 of an inch. Using a set of templates I created a few weeks ago, I set up the parts for two light boxes. While I was letting the slabs set-up, I added some finishing touches to two other light boxes, and prepared a third (which I had unloaded from the bisque kiln) for glazing. The weather slowed the drying of my slabs and I left them covered in plastic on a plaster board to dry gradually overnight.
Tomorrow I will begin to cast providing my molds are dry enough, and I will construct the light boxes. Once they are slightly beyond the leather hard state I will begin to carve organic patterns with varying textures, allowing for differing degrees of thickness to play with the appearance of the light shining through. I will begin several different glazes tests for these pieces as well.
The gas kiln won't be cool enough to open for about 2 to three days from now, but I will report back with news of its success!
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