All posts by KaratsuPots

Bisque 素焼き

Today is the first load of bisque aimed at the fall firing of the wood kiln.  About 28 ware boards worth of pots, I really tried to get as much packed in as possible, to maximize the gas used.

I don’t pack glaze firings very tight because I want the calories getting around to  everything, but for bisque I’m not too picky.
700C – 750C is my usual peak temp,  I like the ware to be very absorbent for glazing, however the resulting ware is quite fragile and needs careful handling.

This time around there are quite a few slab plates of various shapes and sizes, which I am a bit worried will crack. These are stacked on spacers, then more spacers between stacked plates, because I don’t want to take any chances with cracking. The rest of everything is pretty safe, so packed and stacked without too much thought other than to get as much in as possible.

Clay/Centipede Storage

In 2010, when we started digging the trench for the wood kiln, we found a seam of clay from about 60cm – 90cm down. This 30cm thick seam stretched as far as we dug, but with varying levels of iron. I ended up keeping a few hundred kilos of the lightest stuff, and it has been taking up space in bags that have been slowly decomposing over the last 3 – 4 years.

Finally, I rallied the gumption to get that big pile of clay moved today. First, I built an enclosure on the edge of the property behind the kiln chimney, then I started shoveling. The bags were so far gone that they just tore apart if I moved them, so there ended up being very little heavy lifting.

Scavenged  roadside construction boards.
Scavenged roadside construction boards.

I recently came into a big load of boards used by roadside crews to build temporary retaining walls. They are nice sturdy pine boards (2 1/2 inches thick) and are great for all sorts of projects, although they are not all that great looking.

I ended up just pounding in some steel stakes and tying the boards to them. I looked for some little screw-in brackets to go around the rods and onto the wood, but alas this is Taku, and none of the hardware stores had that sort of hardware.  This happens often, and my go to solution is almost always the same: stainless steel wire. It is cheap, comes in various thicknesses, and pretty much lasts forever once in place.

Stainless steel ties.
Stainless steel ties.

Once two sides were finished, I had a place to put clay, but the storage area is not quite finished. I still plan to put in  one or two dividers, so that I have 2 or 3 sections for storing different types of clay. Here is what it looks like so far:

Clay settling into its new home.
Clay settling into its new home.
Clay from the kiln trench
Clay from the kiln trench
Clay from the neighborhood reservoir
Clay from the neighborhood reservoir

The clay that is still in bags came from about 200 meters away, from the farm reservoir. We drain and muck it out once every 2 years, and that is when I discovered the clay seam.  It is not very refractory clay, but it makes very nice pots if fired to the proper temp.

During the process of moving all of this clay, I ended up killing 4, count ’em 4, centipedes , ranging from medium to gargantuan. Normally I would let them go, but lately I’ve been getting a lot of them in the workshop, and they have  a very nasty bite.

Making Furniture

Nope, not that kind…

These last 2 weeks I have been getting over my fear and loathing of slabs, because I have finally figured out how to keep them from cracking during drying. So, lots of slab plates for starters, then a customer came in who wanted even more in different sizes for his sushi restaurant. This is good high end restaurant, and there is a very high chance of repeat business.

Anyway, I had been using someone else’s risers for my plates, but since I needed my own anyway, I spent a few hours today mixing up some fireclay and press molded my own risers.  Below are pictures of the very simple process. These risers will be used during drying and also during firing to support corners and edges. The fire clay is very rough and easy to grind off if the glaze runs and sticks to it.

Riser jig. I just press in a clay coil then trim lengthwise with a wire.
Riser jig. I just press in a clay coil then trim lengthwise with a wire.
Risers sitting on plaster to stiffen.
Risers sitting on plaster to stiffen.
Risers before cutting
Risers before cutting
After cutting, about 360 risers.
After cutting, about 360 risers.

Here are some of the plates that have been made so far:

 

Slabs cut and laid to rest/stiffen for a night.
Slabs cut and laid to rest/stiffen for a night.
Stiffened slabs cut to match template.
Stiffened slabs cut to match template.
Finished and supported with risers.
Finished and supported with risers.
Natural stone texture.
Natural stone texture.
Four sided slab plates, 22cm x 15cm.
Four sided slab plates, 22cm x 15cm.
Square slab plates, 25cm square
Square slab plates, 25cm square
Thrown/stretched slab 'Abalone' plates
Thrown/stretched slab ‘Abalone’ plates
More slab plates, this time much more flat, so that picking up sushi is easy.
More slab plates, this time much more flat, so that picking up sushi is easy.

Processing Clay and Ash

In a recent massive cleaning around and in the studio, I changed things around to utilize some of the outside space more efficiently. One of the most important things is that I now, again, have a setup for processing clay and ash that I have collected and burned.

I had been getting close to finishing off my stores of collected clay that I processed some years back, time to start doing it again. I think I have a better system this time, and I have an inexhaustible supply of pine ash for now, too.

I have buckets, bags, and jars full of old collected clay and dry trimmings that need recycling. It should take some months to get it all blunged and pugged.

Collected clay that has literally been sitting around for years.
Collected clay that has literally been sitting around for years.

The Choppage ‘cho’ ‘pah’ gay’, is a traditional Korean tool for scooping off clay and other materials without disturbing everything underneath. It works much better than a ladle. I couldn’t find anyone who made them anymore, but my mentor still had one which is kindly letting me borrow.

Clay washing bucket setup, and scooping tool, called choppage.
Clay washing bucket setup, and scooping tool, called choppage.

I just agitate the material in the bottom bucket, wait, and scoop off the stuff that settles last.
Then, later after it settles in the upper bucket, I siphon the water back down into the main bucket. When enough of the upper bucket fills with material, I dump it into cloth lined basket or plaster to get out the excess water.

After returning water back into the main bucket from the 'good stuff' bucket.
After returning water back into the main bucket from the ‘good stuff’ bucket.

With the ash, the process is the same, but after I get out the good fine ash I transfer it into another bucket and wash it some more to get out the nasties. The nasties cause problems with glazing sometimes and I don’t like them. I do save the water containing the nasties for other uses.

Pine ash bucket setup, main on bottom, fine up top.
Pine ash bucket setup, main on bottom, fine up top.

The leftover rough ash stuff seems like a waste to just throw away, so I am thinking about ball milling it to see if it can be useful in some other way. We’ll see…

The leftovers after the good stuff is scooped off.
The leftovers after the good stuff is scooped off.

 

Scooping with the choppage tool.
Scooping with the choppage tool.

The sieve is 120 mesh, because I lucked into a cheap recycled sieve. I would usually use 100 mesh, so it is not much of a difference.

Dumping through sieve which is sitting on the bucket mouth.
Dumping through sieve which is sitting on the bucket mouth.

A Week of Good Pots

I’ve just come off of a week of pot showing and selling, sharing space with some very fine young (and older) potters who are making crazy good work. This last week was Karatsu Yakimon Matsuri, which ran concurrently with Arita Touki-Ichi. This was the third year for the Karatsu event, and attendance jumped to 100,000, from 70,000 last year.

The theme was tableware, and there were many collaborative exhibits between potters and chefs. What a great time it was to see all of the wonderful work. Gave me a LOT of new ideas and inspiration, as well as some great feedback from customers and restaurant owners.

I had been scheduled to go to the Mungyeong Teabowl Festival, however the ferry accident resulted in most or all of the spring holiday’s festivals being cancelled or postponed.

 

Chosen Karatsu vase with wisteria.
Chosen Karatsu vase with wisteria.
Chosen Karatsu bucket. (Oke, 桶)
Chosen Karatsu bucket. (Oke, 桶)
Kuro Karatsu and Muji Karatsu guinomi. The kuro sold on the last day.
Kuro Karatsu and Muji Karatsu guinomi. The kuro sold on the last day.
Chosen Karatsu bucket. (Oke, 桶)
Chosen Karatsu bucket. (Oke, 桶)
Ao Karatsu Tower
Ao Karatsu Tower
Chosen Karatsu Teabowl
Chosen Karatsu Teabowl
Paddled Jar with gold repair
Paddled Jar with gold repair
Ao Karatsu platter, 50cm
Ao Karatsu platter, 50cm

Views of a repaired teabowl

This is the teabowl that fell into the firebox during the last firing and broke into about 12 pieces. After falling and breaking, the firing continued, and the larger shards warped a bit, making it hard to get the pieces to fit just right.

Everything went back together, but some of the spaces were 1mm wide or more, and a lot of filling was required. Not only that, but the edges of the larger pieces didn’t meet evenly, making a lot of uneven fill lines. I thought about grinding down the higher edges, but in the end decided against that, because the fill lines were already so wide in some places.

So, here is the finished piece, with the lacquer and gold brushed on over the fill lines. A pro could have made thinner, more even lines probably, but it was good practice for me. A few more days to dry completely, then it will be time to whip up some tea…

IMG01410

IMG01408

IMG01407

 

IMG01405

IMG01404

IMG01403

IMG01402

 

IMG01411