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I love the look of pots all laid out whether they be green ware or pots waiting to be loaded in the gas kiln, as these are. The mugs almost remind me of a regiment of soldiers, or a tightly packed school of fish all swimming in the same direction.
I’ve been finishing up a gas firing this morning, busily trying to keep the gas tank from freezing up until the propane truck finally makes it here this afternoon. We’re cutting it pretty close though.. down to less than 5% in the tank and I have the garden hose dribbling some water on it so I don’t lose gas pressure completely. Thankfully though, cone 9 is bending evenly top and bottom so we’re in the home stretch.
I made a little adjustment to the way my target bricks were positioned this time (an experiment) in hopes of making the firing more efficient. Evidently it has had some effect because the last time the kiln was stacked similarly, I had a good cone or 2 difference from top to bottom . I guess I’ll only know for sure once the kiln is opened.
Looking forward to this kiln opening. I have several pots in there with clay from our new clay deposit I mentioned in my last post.
Several years ago, when I was *very* new to clay, I attended my very first clay conference. It was really my first introduction to the clay community. I remember it being a wonderful and unforgettable experience. I got to try rakuing for the very first time at the preliminary workshop hosted by Ottawa Valley artist Leta Cormier in her, as I remember, extremely immaculate studio. I also got to take part in my first mug exchange in which I remember receiving a lovely salt-glazed mug by potter Jackie Seaton. My name was even drawn and I won some nice oriental brushes. But that was not all (and this was the pinnacle for me), John Leach, of Muchelney Pottery, was the main presenter. His pots were like nothing I had seen before (I told you I was new to clay) and I was impressed by what a real person he was … very gracious, generous, and down to earth. He left a lasting impression on me.
I recently discovered John’s brother Simon Leach has posted a series of videos on YouTube over the last year or so, showing demos, kilns, visits back to England and to friends’ studios, his philosophies, etc etc. What I like is he presents things face on and shares his victories and disappointments, the good and the bad, taking it all in stride. I don’t think a lot of people are aware how hard it can be to be a potter and that things, quite beyond your control, can go extremely wrong after many, many hours of hard work, and all for naught. Here is the 2nd of 2 of Simon’s videos taken while unloading Seth Cardew‘s kiln:
So Its Tuesday night (Wednesday morning), its 12:20 am, and I’m up waiting for the cone to bend in the bisque so I can turn it off and go to bed. Grabbed a cat nap a little while ago and though still a little bleary eyed, ready for the final stretch.
No matter how organized you *think* you are, the last 2 weeks leading up to a show tend to be somewhat more tense than usual, what with trying to make sure you have enough fired and hoping everything makes it through the firings okay (can you ever have enough pots?!). With the studio more or less a construction zone, I have to work around the weather forcast when it comes to glazing and other related outdoor activities. Potting is a lot like a well coordinated dancing act.. timing is everything.
The first fall show is just over a week away. The roof is finally on the studio (yay!) though rain can still blow through a bit from the sides, and I am still working out the house and around everything else. Pushing things through the bisque as I can, relying soley on the small electric kiln since our other 2 larger ones are out of commission due to faulty bits that still need replacing. Coming to the realization that tomorrow or the next day are probably my very last throwing days for the show Oct 4 & 5 (The George Ohr Festival in Biloxi, MS) and after that its just glazing and firing and hoping for good weather! Doh.. forgot to order that replacement part for the canopy. Tomorrow.
…And so show season begins!
When we originally built our kiln in 2000, we used all recycled brick and built it around the size of shelves we already had. It was a flat top, built mainly of stacked arch brick for the walls and a fiber (ceramic blanket) and heavy sheet metal roof. Not fancy, but we had a kiln and didn’t have to spend much money to put it all together.
It took at least 7 years of painstaking tweaking and firing before I really got to know its ways. About 5 years ago a dog we had knocked over the entire stack of old brick we were using for the kiln door, breaking most of them!! (..sigh) Long story short, it has been a struggle from the get-go to achieve reduction with any reliability, if at all.
As I think I mentioned in my last post, the old kiln as it was is no more. The flat roof – gone. The danger of fiber bits falling down into pots if you accidentally brushed the roof of the kiln with your head when stacking/loading – gone. The flat top was replaced with a retrofitted sprung arch and we finally were able to get new brick for the door. Extra fiber and roofing tin wraps the outer walls now as well.
The other exciting change made was replacing the old severely warped cordite shelves in favor of 6 new nitride bonded silicon carbide shelves. As you can see in the pictures, some of the old shelves were warped an inch and a half to two inches in places (I put one of the new nitride bonded shelves beside the stack of old shelves to show the difference in thickness and flatness). As with a wood or soda fire, loading typically involved painstakingly “wadding” each and every pot for the firing with a mix of 60/40 china clay to alumina hydrate. It was the only solution I could see to prevent warping. I have several potter friends who have those zoomy Advancer shelves that run about $100 a shelf in the size I was looking at. The nitride bonded are a step down from the Advancers, but are a lot less cost prohibitive, costing maybe $20 or so dollars more than a comparably sized cordite shelf.
These new nitride bonded shelves weigh all of 11 pounds (the old cordite shelves in comparison weighed 44 pounds!), so loading the kiln takes a lot less of a physical toll on me and I can load it independently. I still do wad some – little teeny wads – (vs using kiln wash or sprinkling alumina hydrate on the shelves), especially on those clay bodies I might be firing that might be a bit tighter than our native clay to prevent sticking, Loading takes a fraction of the time as does the preparation of the wadding itself. Now that I have flat shelves, the wads can be glued on in advance as well.
The new arch in combination with the new flat shelves gives me at least, I am guessing an extra foot of stacking space. Not only that but the kiln now reduces and fires more efficiently using about a third less propane per firing. With the rising price of propane ($264 for 75 gallons this last delivery), the upgrades to the kiln and shelves couldn’t have come at any better time. (Better for the environment as well.)
As an aside, we got our new shelves and brick from Larkin Refractory Solutions in Atlanta. Wonderful customer service and knowledgeable staff.
The Gulf Coast Kiln Walk Society, out of Navarare, Florida, has some pretty cool and exciting things coming up this fall, including the second firing of their 32 foot anagama kiln which they built and fired for the first time last year.
Mr Masayoshi Shimizu from Iwade City, Japan, will be arriving November 27th to orchestrate the firing which will take place the first week of December.
Events relating to the firing include:
- Dec 2-4 – Glazing and loading of the kiln
- Dec 4 – The Ceremonial Lighting of the Anagama Kiln
- Dec 16 – 9:00 am Kiln opening
- Dec 16 – 9:00 am – 4:00 pm – 1st Annual Woodstoke Pottery Festival
While the deadline for members to submit a piece to the firing has passed, its a great opportunity to and see a master at work and find out what the excitement of an anagama firing is all about.
Mr Shimizu will also be holding a master class and slide presentation at the University of West Florida on Wednesday, Nov 29.
As per the Kilnwalk calendar, please note that all events are free and open to the public. Please click on the links above or call 850-939-2744 for more info.
Hope to see you there!
In the past few months, I’ve posted pictures of some of our pottery here on the blog and on our web site, now here is a little info about it.
All our raku vessels, are individually formed, carved, brush-glazed, and fired, using an American variation of the Japanese firing technique known as raku.
A glazed pot is heated to approximately 1825 degrees Fahrenheit. Its then taken from the kiln while its still red-hot, gently placed in a bed of pine shavings, and then covered (as you can see in this picture, we use a wheelbarrow or on other occasions in a metal wash tub as our pine shavings receptacle). When the oxygen in the air surrounding the pot is depleted by the flame, the flame then looks to the glaze for more oxygen molecules to consume. A chemical reaction may take place in the glaze, causing spontaneous and random flashes of color and metallic lustre. As the pot cools, a random crackling (or crazing) of the glaze occurs as the clay and the glaze expand and contract at different rates. What also happens is the carbon from the burning shavings fuses to all the unglazed surfaces and cracks in the glaze, turning them black. The piece, still hot, is then extracted from its bed of shavings and is quenched (or rapidly cooled) with water. Doing so not only cools the pot to the touch, but sets the colors before theglazes have a chance to reoxidize. Some of the results can be quite spectacular and its easy to understand the allure of pottery fired in this way. No two peices ever turn out completely the same and every one, in its own way, is one-of-a-kind.
The majority of stoneware clay we use for our functional pottery is from abundant native Alabama clay deposits, usually found within just an hour’s drive of the studio right here in Baldwin Country. The deposit Lowell working on here is right along a local roadside. The clay that seems to work best is whitish or, better yet, almost a bubble gum color. It fires the highest and has the least amount of impurities which is perfect for durable functional ware. Our functional pottery is individually formed, most of it on a potter’s wheel, is individually decorated, and then high-fired in a propane fueled gas kiln to approximately 2400 degrees Fahrenheit.
I’ll have to cover in future posts some of the primitive-fired pieces we do as well as the ongoing journey of the building of our small wood kiln using recycled materials…