Ceramic Arts & Perception — Ceramics Technical
Ceramics Art & Perception

Flame, Smoke and Flying Ash -
Milton Moon experiences the cult of woodfiring

It is 28 years since i visited the place where Arakawa Toyozo lived and worked. As a recipient of a Myer Foundation Geijutsu Fellowship I knew I was following the footsteps of many before me. It wasn't the first time I had experienced the lure of Japan: 18 years earlier, on a troop-carrier still with wartime landing craft winched either side, we ferried back and forth to Japan; but in those days there were restrictions on where one was allowed to travel. Mia Jima, or Shrine Island as I knew it, was accessible and it cast a life-long spell and the port of Kure was interesting with its massive maritime shipbuilding facilities still intact. Hiro is a smallish country town close by and family treasures were being sold to occupation personnel to ease the frugality of the times. It was there I bought my first pot. I still have that Satsuma vase and have even traced its origin, delighted to find that the pottery where it was made is still in existence. They even knew when the pot was made by the quality of the gold over-glaze. Back then I never knew that one day I would make return visits, under my own steam these times, and as a potter.

Fujio Koyama made the Arakawa visit possible. Not only did he make the arrangements but supplied one of his apprentices to accompany me. Invited into the Arakawa home I handled my first Arakawa tea bowl then climbed up the hill to see the famous kiln that fellow Australian Janet Barriskill was later to write about. At first glance it was scarcely distinguishable from the surrounding rubble. It captivated me and I vowed to make one like it, but never have. The nearest I came was a far more respectable looking affair, which only lasted a few years because where it was built was in a country village, and only a hundred metres or so from the Country Fire Service. Fires had almost devastated the area on more than one occasion and the slightest sight or smell of smoke was cause for alarm. During winter, when it should have been possible to fire it without concern, proved difficult because of the unsuspected presence of ground water draining from some nearby source and saturating the hearth. Foolishly, in the early stages of construction I hadn't dug out deeply under the hearth for a foundation of heavy aggregate road metal and drainage rubble to be incorporated into the plan. The wet conditions did produce some marvelousblack' pots, but it was a struggle to get to temperature even when I supplemented the firings with gas. The kiln was finally demolished but the dream to build another one ­ a real Arakawa one the next time ­ still persists.

The word 'anagama' these days is a loosely used term when describing kiln types. My kiln was only partially buried; the back half of the kiln was banked with earth and rubble whereas the front was partially banked up to the kiln entry, which was just large enough to crawl in and out.

There wasn't a proper plan drawn up. I knew the length and width of the chamber size I wanted and, after roughly marking the shape out on the ground, dug out a trench for the bottom row of bricks. This was filled with heavy aggregate concrete and the bricks were laid at the angle the walls were to be. I had decided on a catenary arch structure and this determined the angle of the walls. I had made four arch forms; these had been made the usual way, by hanging a chain on a wall at the width and depth needed. Under the hanging chain were sheets of newspaper on which were traced the curves of the chain. This outline was transferred to scrap timber and the arch shapes were formed. When the arch forms are located in their positions you must chock them up about 5mm or so enabling the chocks to be removed, for the forms to be lowered, after the arch bricks are laid. It is also advisable to screw the forms together so they can be disassembled inside the kiln to allow easy removal after the bricklaying is completed.

I had a neighbour who was both potter and skilled worker in timber. From scrap timber he cut me long lathes thin enough to bend. These were laced over the basic arch supports. When you lace timber this way it is surprising how strong the supporting structure becomes. It was then a simple matter of deciding where the door should be, making an arch and putting it in place. The rest was simple brick laying, using scrap clay loaded with sand and grog and also using wedges of harder clay to fill in the top gaps as the bricks spread apart following the curve of the forms.3 At rear of the kiln I had determined the flue size needed and, at the front, the size of the firebox. As LP gas was to be used as both an initial and supplementary fuel to the wood, a large chimneystack wasn't really necessary. Firing this way made the task much less arduous although there were times when I enjoyed the help of some volunteers to ease the burden of stoking. Having gas also meant that on occasions I could choose quite green and sappy eucalyptus to get some marvelous colour flashes from complex hydrocarbons and timber gums without dropping temperature. Purists might find the practice of using both gas and wood not all that authentic but we must make the choices that suit our individual situations. One good point about using the two fuels together is that ash is almost blown on to the ware, especially when you stir up the ash bed.

The firebox was a simple affair but it was quite large for such a small kiln and it was possible to fire with wood only if desired. The bagwall was chequered and this allowed some direct flames on the front-stacked pots. The flue exit at the back could be blocked with a brick to cut down the size if necessary. On this particular kiln I was able to control reduction by using a broken kiln shelf to close down the top of the stack, although on other kilns I have built it was possible to devise a damper built into the bottom of the stack. If I was using both fuels at once it was possible to bring about reduction just by introducing green timber.

There are basic rules to be followed in kiln-building and one I subscribe to is 'keep it simple'. During my woodfiring learning days I recall discussing one particular kiln with the late John Chappell, during his fateful trip to Australia from Japan. I had found it impossible to get above a certain temperature and was almost in despair. He solved the problem in half a minute and gave me the best lesson I could have at that time. His advice was: Avoid complicated designs and make sure that bagwall heights and flue exits and chimney height can be altered without having to engage in massive rebuilding. It was good advice. The next best advice I received about woodfiring was, Don't choke your ash-pit, keep your stoked fuel both loose and open and always keep a trace of smoke coming out the chimney; that way you know your temperature is more likely to be going up, not down. There are other fireboxes that are more labour-saving and there is no shortage of plans. But if you want to enjoy the thought of a contest with a fairly rudimentary kiln, this small one I built could be a good start. You might also learn about woodfiring at the same time. But few things in life are as easy as they sound.

Milton Moon is a ceramic artist living in South Australia. He has had a distinguished career as a potter for more than 50 years.

 

 

 

Ceramics Art & Perception — Cermaics Technical
Ceramic Arts & Perception — Ceramics Technical
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