May 30, 2018
Kiln Pointer from Paragon:
A Kiln Mishap (Firing a Plastic Level)
When something goes wrong with a kiln, it is easy to assume the worst. But from my experience, most kiln repairs are quick and far less expensive than you would expect.
For instance, a customer named Katie wrote, “I fuse glass in a Janus-1613. This morning I left a 1" plastic circular level on top of some glass when I fired the kiln. (I’m not a morning person, obviously.) I caught the error at about 738°F (392°C) when I noticed a horrible smell. A brief peek into the kiln showed the black level melted onto the glass. The floor of the kiln appeared charcoal colored. Previously it was kiln wash pink. I closed the lid, pulled out the peephole plug and unplugged the kiln to let it cool. What should I do to clean the kiln?”

I suggested vacuuming the kiln and firing it to burn off the plastic residue. “But do not vacuum the thermocouple,” I added. “The vacuum cleaner can damage the controller by sending a static charge through the thermocouple to the controller.” (The thermocouple is the small rod that extends into the kiln.)
Two days later, Katie wrote, “I’m delighted to report that the kiln issue appears to have been resolved successfully.
“The black material on the floor of the kiln did wipe off somewhat but not fully. It didn’t vacuum off. After wiping and vacuuming, and vacuuming and wiping, I fired the kiln. At 1385°F (751°C) the kiln floor still appeared dark, and an acrid odor continued to emanate from the kiln. By 1450°F (787°C) the floor was no longer gray and the odor was markedly reduced.”

(Top photo: After the mishap. Center: After cleaning and firing. Bottom: The melted plastic level.) 
The discolored kiln floor.
After cleaning and firing.
The melted plastic level.
Recent Q&As
Q. I need to replace the controller on an older GL-24AD kiln that has a Sentry 2.0. Will a new wiring harness and any additional wiring will be required to fit the current style of controller?
A. You will not need a wiring harness since you are switching out a Sentry 2.0 12-key controller for another. You would need a wiring harness only if you were replacing the DTC 600 through 1000 series controllers with the Sentry.
The Sentinel Smart Touch controller can be installed on the GL-24AD kilns without having to order a wiring harness. The Sentinel uses the same wiring harness as the Sentry 2.0 12-key, so they are interchangeable.

Memorable Quote
“There seems to be some perverse human characteristic that likes to make easy things difficult.” --Warren Buffett [This applies to kiln repair! --Arnold]
One morning as I drove down the alley, I saw the neighbor who lives at the end of the block. I had never met him before. When he looked up, I waved and smiled. With a look of surprise and shyness, he waved and smiled back. To make eye contact and share a few seconds of recognition with a stranger seems powerfully real in an age when we interact with hundreds of people we never meet.

Thank you,
With best wishes,
Arnold Howard
Paragon Industries, L.P. – Better Designed Kilns
2011 South Town East Blvd.,
Mesquite, Texas 75149-1122
Voice: 972-288-7557 & 800-876-4328 / Fax: 972-222-0646 /
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