This is Round 2 of the deep slump firing.
We are trying to take out the kinks in our kiln and our deep slump program. The following program settings for our deep slump firing for our skutt kiln where the results of the images to the left of this post.
Ramp Target Deg/Hr Hold
- 150 500 .15
- 250 1100 .05
- 100 1200 .20
- 9999 950 .60
- 150 800 .10
- 300 225 0
Now If you notice on the picture on the left just above the center is a bellow button the corresponds to the air hole drilled into the ceramic mold. It is obvious from the belly button the the way the glass piece took the complete shape of the bottom of the ceramics mold that the kiln was definitly hot enough. In fact because of the belly button I would wager the kiln was too hot.
Moral of the story. Looking at the 20 minute hold at the 1200 temp, I would think that this might be excessive especially considering that I go sooooo slowly at 100 degrees per hour between 1100 and 1200. I am going to try again with another thick piece of glass but holding only .5 minutes not the .20.
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