Tag Archives: kiln

Shell geekery for shell geeks

Warning! Geek alert!

Today on the way back from teaching, I stopped by the seaside shell pile to collect some cockle shells for firing. Though I usually don’t find “the good ones”, today I got lucky. Pictured below are the two types in the area. The thin type with the many, shallow grooves comprises about 99% of what one can find, so I usually use those, but today I found quite a few of the deeply grooved bumpy, thick shells. These are better for standing pots on because they are thicker and don’t collapse in the firing, so they don’t need to be stuffed with fire clay, at least for small to medium sized items. They also leave a more interesting mark on the pot.

“Hi, I’m Mike and I’m a shell wadding geek.”

“Hi Mike” (SWG Anonymous group murmurs)

Gas kiln with saggars

People sometimes lament the limited effects possible in gas and electric kilns compared to wood kilns, but there are ways to get many interesting effects in gas and electric if you use your imagination and do some experimentation.

This time around I loaded about half of the kiln with saggared ware. 4 incense burners, 3 sake cup refires, 2 boxes, 2 teabowls, and 1 frog toilet (in porcelain, no less).

The incense burners came out most interesting, with a lot of deformation occurring in the clay, which was the goal. Nakayama kun wanted some burner bodies that were deformed and all around ‘grungy’ to fit with silver lids. They were wrapped in rice straw rope that had been soaked in a saturated solution of soda ash, mixed with some feldspar, the idea being to get some focused area effects on the pot surfaces. The soda ate into the clay in places and fluxed the feldspar nicely. One of the burners completely collapsed and stuck to the saggar and the adjacent burner, but I’ll be able to keep 2 out of the 3.

Two of the teabowls, with iron based glazes turned out nicely, but one (the black one) stuck to the saggar and will need some repair on the lip. Nakayama kun is going to do a silver repair on the lip, and I’ll post a picture when it is done. The other, and iron saturate glazed bowl, turned out nicely but I really can’t decide if I like the glaze color or not. Need to whip up some tea in it to see if it shows off the tea color well or not.

The porcelain ring boxes were a complete failure, with cooling fractures I think. I drizzled in a soda/spar slurry on the insides and it was waaay too thick. I think its expansion and/or contraction fractured the pots.

It’s Official

The kiln is finished. Yep, you heard right. Done. I can hardly believe it myself.

Cleaning up the front area and getting the concrete in was the last job, and it is done. Now, working on the kiln will consist of playing with the flue dimensions and firing it, something I am looking forward to, and have started getting work ready for the  upcoming October firing.

I pulled the forms off this morning and cleaned up the concrete. The sump form had collapsed under the weight of the concrete, so I didn’t get the nice oval I was aiming for, and I had to go in with a hammer drill and concrete bit to clean out some of the concrete that had encroached into the sump area. It was still not quite cured, so not too difficult to break up.

Though I imagine water will still rise in the mouth of the kiln, it won’t be dirty runoff, and the walls of the stoking area will not be eroding every time we get rain. Once I get my hands on an automatic sump pump, I’ll be able to cover the sump and forget about it. Yay!

Actually, looking at the front area again, if we could think of a way to create a waterproof wall across the front of the kiln, we could have the first kiln heated jacuzzi. In fact, we could probably ‘soak and stoke’, relaxing in the hot tub while simultaneously firing the kiln to cone 13.

Cupholders

How do you know your kiln is a luxury model? When you built it/had it built, did you really think of everything? How do you know that you have THE KILN that shows everyone you are a winner? a behemoth in the clay world? a demigod of ceramic art? Why, cup-holders, of course.

Kamadashi / and a nasty case of the runs

I unloaded the kiln yesterday evening, confirming my suspicions about my glazing skills. While I got some good smaller ‘souvenir’ level work out of the kiln, the chawan and guinomi were for the most part not so good. These are the higher yen items, so I like to get more of those than less, but it does not oft happen. Two problems with them this time: the iron glaze was a bit thin, because the water was a bit too deep in my foot soaking dish, and my band of rice straw ash glaze at the top was a bit too thick.

The pieces that I needed for the upcoming show were the small dishes and yunomi, and for the most part they came out great, aside from about 10 that really ran, and had super duper pinholing. The smaller dishes that I tried out my copper green on turned out nicely as well, looking like a cross between an Oribe green and a Nuka Seiji.

I’ll post pictures of some individual pieces in the next few days, but for now here are the unloading pictures:

Rain, rain, GO AWAY…. REALLY!

It has been raining cats and dogs since this morning, and we must have gotten about 8 inches in as many hours. Unreal. It is the first time the water has risen in my kiln to a level that would affect pots if they were loaded into the first chamber. In the past it has always stopped short of the front floor but today it was a couple of inches deep in the front floor area.

At least I had good weather yesterday and into early this morning for firing the gas kiln. Turned off the kiln at around 5 am (fired for 18 hours) and when I woke up at 6, it was pouring. Later in the day, I peeked into the kiln when it was still around 700C. Snapped a couple of pictures, with and w/o the flash. The first glance doesn’t look too good. Ame yu was a bit too thin, I think, but won’t know for sure until I open the kiln up completely and have a good look. One thing I am happy about is that the new clay blend I was testing seems to have stayed together nicely, no bad slumping (a little slumping, I like).