Cool Waiting

I was just out peeking in the spy holes. The pyrometer is reading 540 degrees still so it is going to be a while. The rule of thumb I was given was that if you could stick a roll of paper into the spy hole and it didn’t burn or smoke, you could open the kiln. [Fahrenheit 451 for Ray Bradbury fans] I have done this, but found the “Ting Ting Ting” sound of the glazes crazing just too nerve racking. So, I go a little slower…

The process of the firing seemed to go well. I did it a little different this time. I have been starting the pilot burners at 10 or 11:00 pm the night before and letting them burn until I get up the next day and light the main burners. The kiln would reach about 450 degrees. This time I just left it until the morning of the day of the firing. I lit the pilots let them burn an hour and then cracked on the mains and let them burn an hour. From there I boosted the pressure 1 psi and hour until I reached 4 psi. I set then damper at 5 inches open and it is in cruise control. When Cone 010 goes down, I pull the brick out of the passive damper and let the kiln go for an hour in body reduction. Usually Cone 080 goes down during this. Back in cruise control the kiln climbs towards Cone 10 (~2350 degrees). I finished up maybe an hour later and saved a few bucks.

It is then time for the fun. I mix 3 gallons of hot water with 3 lbs. soda ash, 1 lbs. salt and ¼ lb. borax. I put this in a sprayer, open ports in the kiln and spray.









When Cone 10 goes down, I shut the burners off and let the kiln cool until 1900 degrees. At this point, I relight the burners and hold that temperature for an hour to foster crystal growth in the glazes. This adds depth to their color if I can get it to happen. The whole firing process is like that. You try your best to control it, but in the end, the kiln Gods give you what they want.

Hijacked

The pots that were going to be fired from the last post were hijacked over to Rob's wood kiln and fired there. I got hijacked to do some engineering work so the kiln - and the blog - has sat waiting. Yesterday, I finally fired the kiln.

This was the kiln's first cone 10 firing. I have been thinking about moving to the cone 6 to 7 range (lower temperature) to save fuel and wear and tear on the kiln. It has been a debate going on in my head for quite some time. On the plus side is the savings in time, money and being slightly more "green" (if potters can be considered at all green in their processes). On the minus side is the change in glazes, experimentation required, and adjustments to aesthetics that are needed to shift from what I have been doing at cone 10. I think in the end I will make the shift, but in true Jody fashion, I will ponder it for a while longer.

However, I did want to prove that the kiln could fire to cone 10. That was the design temperature I set. The guy who sold me the burners for the kiln, advised that the kiln might not be able to make it to temperature and suggested bigger burners. I redid my numbers, checked them twice and stuck with the smaller burners (which are pretty damn big to begin with). But... I used to stand on the deck of the launch barge offshore, ready to push the structure off the barge into the water after 9 months of engineering and wonder, will it realy float like I calculated it would? They always did, but until it was out there bobbing in the sea, I kept running through the numbers in my head. So, at least once, I had to go to the design temperature of cone 10.

It made it no problem. In fact, I had to hold the burners back.

Kiln opening will be Friday. My youngest daughter is coming for a visit on her way back to Texas so I will wait until she is here.

Glaze and Load

Slowly getting ready to fire the kiln in between house projects and yard work. Some quick shots to show the process. Cone packs tell you how much heat you have in the ware.



My friend Rob Harvey gave me a supply of wood ash from his wood stove. It has to be sieved through a series of screens to remove the large junks and make sure it is well mixed. The resulting ash is combined with a clay to make a glaze.



The shelves have all been cleaned and coated with a "wash" that helps prevent any glazes that drip from becoming a permanent part of the shelves.



For the bigger pots, the glaze is sprayed on.



Here are a few of the smaller pots waiting to be loaded.



More to come soon.

Waiting on the kiln opening.

Even though I only have one pot and 9 test tiles in the kiln, I can't wait to un-brick the door and see what the Kiln God gave us. I posted some pictures of the firing on Firing@CreekBendPottery.

I had some sad news this weekend. The small catenary arch, test kiln named "Kitten" that I built at the Appalachian Center for Craft is no more. Owing to a problem with the soda kiln, the bureaucrats in TTU's administration decided that the kilns had to be moved from where they have been for the last 20 years. Kitten just wasn't made to be portable. Oh well, she served well for a while.

I am anxious to get back to building my kiln.

Done firing

We finished salting the kiln at 3:45 AM and I just got home at 4:00 AM. Will post pictures and details on firng@CreekBend Pottery after I catch some sleep. It seemed to go well.

Wood Firing at Creek Bend Pottery

Last week it was DIY, this week it is a firing of the wood kiln tomorrow and the White Oak Craft Fair in Woodbury, TN at the end of the week. If you are interested in following the firing I will be posting on the blog Firing@CreekBendPottery over the next couple of days. If the craft fair is successful, I may post some about it here. If it is not, I may be hiding under a basket somewhere...