Well, the glaze kiln is out. Most pieces came through beautifully. Most of the pieces that I put cookies under because they were glazed too close to the bottom worked just fine.
However. There were two pieces that don’t seem to have been made of a Cone 6 stoneware clay. They both melted onto the cookies I put under. No, the glaze didn’t run. The bowls melted, ever-so-slightly. One was red on the inside and brown on the outside. It actually still looks okay. It morphed into an oval, and the cookie is permanently stuck to the bottom, but it looks cool. The other piece, though… I’m really hoping it wasn’t our recycled, aka Free, clay. Not only did it stick to the cookie, the clay bubbled. The brown glaze they used worked fine, but the white glaze just bubbled like crazy. It looks like a baking experiment gone wrong.
So – I’m putting these on the shelf with notes. If you hear someone complaining about their pieces being melted, please direct them here to Talk, or to me at my normal spot in the Common Room.
And – if you have clay that is Cone 04 clay, or terracotta, the correct way to have it run thru a glaze kiln is to put the piece on the greenware shelves with a note that says it is a low-fire clay. Go ahead and specific what Cone your glaze says to fire to. We normally fire the bisque kiln at Cone 05, but it’s doesn’t make a big difference to the bisque to be fired at Cone 04 or 06. That’s an easy adjustment. Also, if you got a low-fire clay, you can’t use the Cone 5-6 glazes on it. At best you wind up like the brown bowl – pretty, but your form is starting to slump.