|Someone was going to fix it up, but never got around to it - that is until I got it!|
|After a lot of hard work she fires great now!|
|I changed this kiln from a propane-fired updraft into a natural gas-fired downdraft by adding Ward Burners with Baso valves and a chimney stack lined with Kaowool sleeves.|
|Burner ports and the exit flue cut into the back wall level with the floor.|
The flue of my kiln is now level with the floor instead of being up on the roof. The hot gases exit the flue into a stack of bricks where I have a kiln shelf that serves as a damper. Above that is chimney made of Kaowool sleeves surrounded by sheet metal pipes. It's a very effective system and it is outlined in the 21st Century Kiln book. The only problem I ran into was that my first shipment of Kaowool sleeves arrived damaged from Smith Sharpe Refractories. They sent out a second batch which arrived intact, but it did slow the construction process down by a week.
I fire this kiln really quickly. I warm the kiln up to 400° F in two hours using just the pilot light burners. I do this to baby the Thermal Light kiln shelves I use. Then it goes from 400° F to cone 10 in just 4 hours. After that I do a controlled cool for two hours between 1900° F and 1500° F. The kiln really reaches cone 10 in just 4 hours, but with the warm up and controlled cooling the overall firing takes 8 hours.