Friday, September 30, 2016
The Blackbird Pie is Finished
I glazed and fired the Great Twenty Four Blackbird Escape and attached the hanging wire to the back, so it's ready to take to the show Sunday morning.
When I took it out of the kiln I was dismayed to see three problems. First, the pie crust had cracked - you can see the crack under the left wing of the bottom bird. Second, the mouse's tail cracked. And third, the pie crust colors came out AWFUL!!! I did test fires of my colors, using the same clay as the pie and firing to the same temperature with the same firing sequence and they were fine. But, somehow in the actual firing they came out different.
I always seem to have problems working with stoneware in a fairly large size. I don't like the fact that the bisque fire is at a lower temperature than the final fire. With eartenware, it's the opposite - the bisque fire is at a higher temperature than the final fire. I think this means that with the stoneware in the final fire the clay still shrinks and reacts to the heat.
For the first few pieces of stoneware that I made I fired the bisque firing at the same temp as the final fire - cone 5 - and everything worked OK. Then people told me that the bisque firing should only be to cone 04 or the glaze might not stick. I just don't know. I'll have to research it I guess.