Tuesday, September 05, 2006

All fired up...

But not really. I loaded a bisque firing today. The pots have been ready for about a week—but I was not! I wasn’t because of all the kiln maintenance I needed to do! Several of my shelves were badly messed up in the last glaze firing. It was not just glaze running down the side of a pot and dripping onto the shelf—though that happened, too. One of the test plates deposited big blogs of glass onto the shelf in several spots under the plate! And a couple of the run-offs from the test bowls were so serious that the foot of the bowl broke off and stuck to the shelf! I’ve cleaned up glaze spills before but those were such that I could tap the glaze off with a chisel and hammer. But this time there was no budging these spills with the chisel. Jim suggested using the Dremel tool to grind the glaze off. And that is what I am doing (notice the present tense after 3 days work.) The glaze burned down into the shelf—through the kiln wash—so it does have to be ground out. In addition to this mess, other shelves were in need of a fresh coat of kiln wash. All in all a dreadful lot of work. But I got enough of it done so that I could start the bisque firing by noon today. I still have 4 shelves to do more work on before I can use them again. Fortunately, I recently bought some extra shelves that were on sale—they are a little smaller than my kiln’s shelves but they work and today made it possible to go ahead with the firing.

I am now more aware of the need to become a better observer. I know that some of my glazes ‘spit’—but I have not tried to figure out which ones are doing the spitting. And now after the bad flows and dumping of glazes I am making a real effort to know which glazes can’t be mixed—which was the cause of the worst problems in the last firing. On the test bowls I had dipped the rims in different washes or ash glazes to see what they would do. Where I let the overlap get too close to the foot I got the most serious runs—sticking the foot to the shelf and melting into the shelf. On the plates I was overlapping glazes to see how they worked together. The biggest mess was putting M&M Clear over Denim and Charcoal! That is the combination that dumped the big piles of glazes on the shelf.

When I unload a glaze firing I am so eager to see the results on the pots that I don’t take note of what has happened to the shelf under each pot. So I want to slow down and try to take it all in. I have gone back and figured out which pieces caused the mess that happened in the last firing. But I still don’t know which glazes are ‘spitting’.

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