There is a new video up on the Karatsupots youtube channel. On it, I explain the process of glazing Chosen Karatsu ware, from applying the ame glaze, to trimming the ame, and subsequent application of the wara glaze.
There is a new video up on the Karatsupots youtube channel. On it, I explain the process of glazing Chosen Karatsu ware, from applying the ame glaze, to trimming the ame, and subsequent application of the wara glaze.
I’m lucky in that I can walk out my door and head up the hill for a walk, and I rarely encounter anyone else.
Today, I was passed by one car and was otherwise completely alone. It was a beautiful spring day after a day of rain and the mountain was lush. Several times on my way up I could smell the wild boars that must have been lurking nearby quietly. I don’t worry about them. The only time I ever see one is when they jump up to run away when I get too close on the road.
The road is roped off now, because of a landslide that damaged the road higher up, but it’s no problem for walkers to go through.
A very nice walk, and a nice clay discovery, I’ll be heading up again from the other side in my car to get some for pots and glaze.
Yesterday’s firing was my first gas firing of this glaze, body, and pigment, and first ever primarily porcelain firing.
This piece’s specs:
Porc:Sandstone body 6:4
Taishu:Ash glaze 7:3 @ 40°
Gosu:Oni-ita pigment 6:4 (7:3)?
Orton cone 7.5 light reduction
Pigment blacker than expected, too thick or maybe not enough reduction?
Body is not vitrified completely at this temp, but pure Izumiyama probably would be. Good for teaware and tableware, but for restaurant use should probably be fired higher.
When I was polishing work from the fall firing yesterday, I noticed two pieces that had been glazed, fired (on shells)glazed again, and fired again (on shells). This isn’t too unusual, but in the case of these two pieces, they were literally fired side by side both times and had the same glazes applied, twice.
The only difference between the pieces is the clay body. The teabowl is clay/sandstone 50/50, and the smaller cup is clay/sandstone 10/90.
Now probably it shouldn’t, but the difference in the fired glaze surface astounds me. And all other things being equal, it must be that 40% difference in clay content that has changed that glaze.
Since the glaze is collected, I don’t have an analysis, but my guess is that the higher alumina content in the higher clay body is responsible for making that high silica glaze go clear, by adding alumina to the glaze matrix and fluxing more of the silica.
The first abalone dish dried successfully, so today I started making more. I also started a small run of shiboridashi teapots. These are always good sellers, because they are easy to use and clean, with no hard to reach holes or metal sieves to collect grime.
I always carve the grooves as early as possible, because as the clay gets harder, it becomes difficult to carve without tear out. Then I put the lids on, so that they dry evenly without warping, and after trimming they will go into the kiln to be fired together, to avoid any warping.
Loading of the first chamber began this morning.
The stack starts at the bottom from back to front. This part of the firing process is very important because it determines where the fire and heat will go during the firing. A bad stack means you will have poor circulation and you’ve doomed the firing even before you’ve lit the fire.
The bottom of the stack is pretty much done, and the ware from 9 ware boards got stacked in there, which is about 80 pots give or take a few.