Tag Archives: wood kiln

Trying Out Something New

I decided to try out a new form to put in the next firing. A clam shaped dish that is a sort of Karatsu standard. They are nothing special, and pretty much everyone makes them, so there seem to be MANY ways to get from point A to point B.

Ko-Karatsu Hamaguri Food Dishes 古唐津 蛤向付
Ko-Karatsu Hamaguri Food Dishes
古唐津 蛤向付

The first thing I always do when trying out something new, is look through my collection of old Karatsu ware pictures and books, to see if I can find an example, with measurements, of what I want to make. Well, this time around it seems that although everyone seems to be making them now, there are very few examples of this form recorded in Karatsu ware related books. Or at least the ones I have in my studio.

I managed to find the same 5 piece set of old Karatsu Hamaguri dishes (clam shaped dishes) in 3  different publications (above). And, none of them show the bottom of the dish, or a closeup of the folded lip that makes the clam shape. I made a few, tried cutting the lip and overlapping, pulling the lip up and folding over, and  a few more things, but all I ended up with were forms that just didn’t click.

Whenever I get stumped, I give my mentor a call. He usually has some advice that gets me out of my hole and gets me back on track. In this case, I asked him if there was some sort of not so obvious ‘trick’ involved in getting the shape right for this particular form. As usual, Tsuruta sensei gave me some very good advice, and even sent me some close up photographs, which helped a lot.  So, here’s what I came up with:

Now, I tried doing the bending and folding at various stages of drying and I’m here to tell you that it is best done when they are still sticky wet. I suppose it depends on your clay, but for the stuff we have around here, bending and folding is like asking for fate to show up in your studio with a big baseball bat.

That said, although it folded better when wet, it had a nasty habit of  unzipping vertically down the pot 10 minutes later. That’s where the extra blob of clay came in handy. It seems that not only is it decorative, but it also keeps the pot together until it stiffens up a bit. Who knew?!

Honestly, these are my favorite discoveries: when I find a decorative element that is actually not  a decorative element at all, but rather an important part of the process cleverly disguised as decoration.

 

Finishing Up The Rear Chamber

Today  the second chamber was finally finished.  I’m not going to brick it in yet, since I have probably forgotten something important, and I want quick access if necessary, until the fire is actually lit. Unbricking an rebricking a door would be on my list of less than desirable ways to spend a day.

While the farther stack was packed with more vanilla type blended clay bodies, this front stack is mostly bodies composed entirely of native clay and stone. Some of it got white slip, but it all got the same clear glaze, so I don’t have to guess too much about temp in the rear chamber when I fire.

Below are some pics of brush deco, slip, and loading. I am happier with a lot of the brush work this time around, but some things still just give me fits, like trying to draw long fluid shrimp whiskers on a round pot. Gah! Need more practice…

TV Crew Visit Studio

Today I had a very nice visit from a television station who did a very nice job of filming the studio, as well as conducting an interview with me for a show segment coming up in August. They filmed the studio and kiln, me making a coil and paddle jar, me glazing a bisqued piece of  similar form, and also finished pieces which had the same glaze as the demo forms.

All in all, a very thorough job on their part, although I have no idea how they will edit everything down to fit in a 5 minute segment.

I had taken photos of the crew to put up on the blog, but apparently the station prefers not to have behind the scenes images of its projects made public, so I am leaving them out for now.

I will, however, include a few images similar to what may show up on the air in a few weeks. Also, once the show airs and the segment is viewable on the internet, I will post a link to it for all this blog’s viewers.

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.

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.