Here are some of the first pots to get cleaned up after the firing last week. I’ll post more over the next few days as I get things cleaned up.
Overall the firing went well, much better than the first two certainly. I’m finally starting to get a grip on how the kiln climbs, and learning not to worry about it too much. We fired both chambers this time and it took roughly 30 hours. Cone 10 flat in front, cone 9 touching in the rear, and cone 13 almost touching in the second chamber. The second chamber is a pleasure to fire, very relaxing after stoking the front. I think I can still get more aggressive with the front, taking the temp up even more, probably somewhere around cone 12 would be good for the rice straw ash glazes.
The intention was to drop cone 6 in the rear and call it quits, but it ended up getting hotter than expected, and the ware in front ended up a little too shiny. However, the middle and rear of the setting came out just about perfectly. Temp from top to bottom was quite even. We stopped stoking the second chamber when cone 11 dropped and clammed everything up after letting some of the excess heat out. Still, when I peeked in the next morning, that second chamber was still glowing, and cone 13 was mostly down. Guess that 1250kg of insulating castable does its job well.
Most of the failures this time around were caused by bad glazing, not the firing. Rice straw ash glazes were universally too thick, and an ash glaze I whipped up hoping to be a nice runny green ended up being a crusty reddish brown. Oops.
Finally! After seemingly endless days of loading, the front is finished. The large pieces in front are most refires with the exception of the large jar to the right. The big white piece in the middle isn’t a pot, it is a large piece of Shirakawa Toseki (porcelain stone from the Shirakawa area near Arita dam). The square right behind it is a piece of sandstone that I cut in two and hollowed out to make a box.
On and off I’ve had requests for pictures of the kiln, so here are some selected photos of it from beginning to completion. Building this kiln was the subject of the first Workshop In Taku, in 2010. The second in the series, Workshop in Taku 2012: The Simple Teabowl, will happen from May 12 – 18, 2012. Full details here:
The series starts not with ‘the kiln’, but ‘the hole’.
Kiln design and expert workshop guidance by Craig Edwards of Minnesota.
Finished the middle setting today. It is mostly saggared ware. I picked up these nifty saggars that are big enough for larger pieces like flower vases and mizusashi. 今日は真ん中のセッティングを完成した。殆んどはボシに入った水指と花入れです。
There is a reason for doing it like this. I’m hoping that the saggars will effectively split the front chamber into two chambers, allowing the front to achieve temp more easily. ボシを使う理由は二つ：独特な効果を得るためと共に壁になって欲しい。大きな火立てになり、部屋が二つに分けられ、手前の部屋は温度が上がりやすくなると想定している。
Just behind the saggars are teapots along the floor, they will be covered in partially to fully covered in embers from the wood stoked directly behind them. The 4 square frame shaped kiln posts are there to prevent the stoked wood from bouncing/rolling down onto the pots. ボシの直ぐ裏には搾り出し急須が置かれている。ここですぐ裏の焚口からの薪が熾きになり、その熾きが急須の周りと上に溜まり、炭化効果が得られると思う。薪が作品の上に転ばないよう、支柱を急須と焚口下の間に置いてある。
Two more things: got a new ember rustling tool which is a shovel head welded onto a pole. this should come in handy for tossing embers and ash around.
So, in indulging my fixation, I had another try at Ido teabowls yesterday. Still not getting it somehow, but am happy with the bowls as bowls. One of the problems was the clay. Too nice, too smooth. It was recycled from some sandy stuff, but in recycling, much of the tooth was lost. I re-added sand, but not enough.
If I hurry, these might make it into the kiln for the Nov. 11 firing. Feldspar glaze, raw glazed and once fired. Who knows, perhaps some good could come of it after all…
These last two summers in Korea got me interested in some variations on coil and paddle techniques. The Korean onggi coil and paddle is very good for quickly making large jars. The south west region of Joellanamdo has a variation on this which uses slabs rather than coils. The slabs are slapped out on the floor in a very even thickness, then added to the pot and paddled. One of the demonstrators of this technique said that if you could slap out an even slab of clay, that was 90% of the battle.
One thing they don’t tell you is the importance of a suitable clay, and the hardness of the clay. It’s hard. Like slap it down on the floor and it doesn’t stick hard. Stretching it out requires a pretty plastic clay, which is somewhat hard to come by in my neck of the woods. However, when I was cleaning out the studio a couple of days back I uncovered some white clay from Seto that I had ordered a few years back for making Oribe ware. I mixed that 50/50 with some Karatsu clay and got something that while not ideal, is somewhat suitable for onggi work.
In the pictures below I slapped out 3 slabs and made a tall jar. If you make all of the slabs first, the construction process goes fairly quickly. It took me about 40 minutes to make the jar. The craftsmen I saw in Korea could make the same jar in 10-15 minutes. This jar is about 50cm tall.