Tuesday, March 16, 2010
All the anticipation & preparation for this - and it is finally happening.
I could barely contain myself. I worked long days glazing and loading the kiln, preparing for Howard to come over and set the burners so we could finally light the fire.
While I bricked up the door, first with hard bricks facing the inside of the kiln, then with soft bricks backing up, Howard set the burners. If you look closely at the middle photo, you can see a thin wire behind (to the right) the burner, which attaches to a thermocouple that rests next to the hot end of the burner (in the far left photo, it peeks through a hole in a side "arm" of the burner. The thermocouple is a safety, that needs to "sense" the flame coming from the burner. If anything ( say, a gust of air) were to blow the burner out, the thermocouple stops the flow of propane. Thus preventing a build-up of highly flammable gas.
After lighting the burners, it took a while to keep the flame very low, yet still lit. We needed to slowly dry out the mortar in the kiln. The weather had been cool and damp all winter, and a lot of moisture had accumulated in the bricks. This was the plan for overnight. A storm was blowing in, and an old door was moved in front of the burner as a windbreak. The burner on the opposite side was safe from incoming breezes.
Once all was set, Howard's partner Deborah, surprised me with a picnic & bottle of wine to "launch the kiln". We toasted the first firing.
I checked the kiln overnight, all was fine, no burners had been blown out. Early the next morning, I slowly turned up the gas. We kept the firing slow as the kiln was steaming heavily. Howard didn't come over until late morning. He wanted to be on hand as we took on the challenge of getting to desired temperature from top-to-bottom and side-to-side.
The photo on the far left is looking through the kiln from one burner hole to the other. When the gas is turned up, it is quite a view to be able to see the glow emitted from the maw of a burner.
On the right-side photo are me & Howard, the kiln guru.
It was a long day and evening, as Howard & I discussed whys & wherefores of kilns and firing. And why I wanted the dampers in, so my glazes would come out as I desired, even though it took much longer to fire that way. About 9:30pm, as the both of us were physically & mentally exhausted we decided the firing was done. Cone 10 was "touching down" in the middle of the back side. Not wanting to over-fire (under-fired pots can always be re-fired, but once they are too hot, it is too late for the pots) the middle of the kiln a usual hot spot, we shut down.