Tuesday, October 21, 2008

October Kiln Firing

Brian crams fuel in blasting off the kiln. Flames travel over 32 feet,
shooting out of the flue pipes almost 5 feet in the air!

The groundhog kiln was fired over October 18-20. As firings go, it was a bit shorter, but always just as grueling. In order to have a successful firing, dry wood is of paramount importance. Even slightly damp wood will cause failure to reach the required 2,300 F degrees and the kiln will hover endlessly at about 2,000 F.

A low pressure system was still over the area as I started the kiln in the afternoon. The weather forecast called for it to be pushed out by a high by evening. The winds were to be around 5-10 mph, which is more than ideal, but I hoped they would die down at dark. Some of the wood was slightly damp feeling and we spread it out in the sunshine to dry completely. I wasn't used to the chilly temps the first evening and wound up pulling my truck up in front of the kiln and ducking in between stokings to warm up.

Near the end of firing a groundhog kiln, a large amount of fuel must be crammed in the firebox to push the temps over the top to shine the glaze and fully mature the clay body. This is called "blasting off" the kiln. Brian is the king of blasting off, a true pyromaniac! He showed up the final few hours of firing to help Sarah and me finish it off.




It will take 4-5 days for the kiln to cool enough to unload. We took the front temps up to cone #12 in hopes of ensuring the back reached required temps. Sometimes, this results in over-firing and some of the pots in front will melt to the kiln floor. An unpleasant mess! We hope this didn't happen. I will post photos of some of the pots when they come out shortly.

Glowing red flue pipes attest to the incredible heat during the final hour or so