Saturday, December 15, 2007

on second thought

After the firing reflections. I had loaded only the top two sections, leaving the lower 2 sections empty hoping to get this one last firing to ^6. I made cone packs with ^4, 5, 6, 7 so I could see exactly how the firing went. ALL the cones were flat in both of the top sections. I had four glazes in that firing: Tenmoku, Gay’s Green, Floating Blue, and Rusty Bronze Satin Matt. I GOT RED. But, I did not get anything else! All except the Tenmoku suffered from over-firing. Gay’s Green and Blue Hare’s Fur have been such dependable, successful glazes it was a huge surprise to see what a sorry mess they came out. Quite a learning lesson. One other time I was very disappointed in some pieces with Blue Hare’s Fur and did not understand why. Now I am sure it was from over-firing.

I got the over-firing because, in my determination to get one more good glaze firing from the almost spent elements, I set the top temperature a bit higher than usual, soaked at the top a bit longer than usual and then soaked again on the way down—as for a red firing. It just got too hot for everything except the Tenmoku.

So, lessons learned: 1) when I want red I should have a whole kiln full of pieces glazed with the same glaze; 2) when I want glossy, I need to let the kiln cool naturally without a hold on the way down; 3) I have got to know my glazes better than I do now. I have been firing all the glazes in pretty much the same way—and always pretty slow.

It was great to get such a nice red bowl! But a great disappointment that the other pieces are unusable. I feel like I understand the glazes a bit better now and that I can probably get the red again when I want it again.

As we reviewed the bowls just out of the kiln Jim suggested that I refire them--they are nicely formed pieces. I said, "NO". My last attempt at refiring was totally unsuccessful, I'm not going to do that again. Well, on second thought I AM going to try to refire! There was a suggestion that if you heat the pots before applying the glaze you can get the glaze to adhere. So I will test out that suggestion. Well, what do I have to lose? Can't (won't) use the pots as they are. And after all, the mantra of the potter is, "Test, test, test", or "experiment, experiment, experiment" and keep good records! Think I can get 'one more firing' out of these elements? Yeah, I think so.

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