To recap:
I was in production mode, making lots of 8.5" full circle plates, 2 layers. An all of a sudden I went from little pin prick bubbles between the layers, to big lumpy bubbles, with the same schedule and same glass. I am now trying to track down all the variables that could have caused this and am working on a the theory that my kiln temp is not really what my Rampmaster is telling me.
I called my kiln manufacturer, Evenheat. How do I test the temp in the kiln is accurate? They suggest I change out my thermocoupler first. They feel these should be changed every 2 years. And they had no pyrometers, but thought a pyrometer was a good idea to double check the kiln. So I've ordered a new thermocoupler and went back on the hunt for a pyrometer.
I called Bullseye. They also like the idea but do not sell pyrometers.
I called the local ceramic store. I talked to the kiln repair guy. He said to skip the pyrometer (tho they do sell them). He suggested I get a bunch of cones for different temps and set them in the kiln (bracketed so I have lower, exact, and a higher temp cone) and do some temp tests at these cone's temp. (He thinks this is a more accurate way to check the kiln temp) He said run the kiln temp up to the exact cone temp, check to see it if starts to bend, after 15 min it should be bent all the way. The lower and upper temp cones will tell me if I am off. Am I explaining this clear?
So, I'm going to try this, and I may still buy a pyrometer.
More Updates, if ya want em.
Carla
Oregon
who usually calls all this stuff by less technical terms