Category Archives: tools

Kickwheel Conversion Finished

The kickwheel conversion is finally finished. Here are some pictures of the flywheel getting put together:

Douglas Fir beams glued up and drying.  After drying, knocked the corners off with a chainsaw, then knocked off corners again to get a basically round shape.
Douglas Fir beams glued up and drying. After drying, knocked the corners off with a chainsaw, then knocked off corners again to get a basically round shape.
Corners knocked off, planed the edge to soften and round.
Corners knocked off, planed the edge to soften and round.
Planed and sanded, ready to go on the frame.
Planed and sanded, ready to go on the frame.
Placed on the frame, spun, and centered. Then, clamped on in place, turned over and screwed in (not shown)
Placed on the frame, spun, and centered. Then, clamped on in place, turned over and screwed in (not shown)
Reassembled and ready to go!
Reassembled and ready to go!

And it was just as easy as that.  Many thanks again to Yamaguchi kun for making the flywheel armature!

And here I am taking it out for a spin:

I have this recurring nightmare…

before every firing of the wood kiln. Actually it is four separate recurring nightmares. In the first, I am loading pots onto normal wood shelves in a fairly standard living room, for some reason not worrying that the lot of it will burn up with the entire house. BUT, for some reason, I always remove all of the lamps and light fixtures, because they and they alone can’t handle the  high temps.

In the second, we are firing the kiln as usual, and we are into the third day, just hours before finishing and I realize that I FORGOT TO LOAD THE KILN… This one is by far the worst of the dreams. The feeling of sudden panic is positively sublime. Very happy to wake up (and realize it was just a dream) after this one…

The next is not quite as bad as the previous, but still pretty unsettling.  It starts out well enough: I have just unloaded a very successful firing and am so happy with it that I decide to fire again. Because it is a dream, I miraculously have enough glazed ware to load the kiln up again in about 2 days (Normally takes me 10). I get everything loaded, and start the fire, but about a day into the firing I realize I ONLY HAVE ONE DAY WORTH OF FIREWOOD! This one also wakes me up with that icky panicky feeling.

The third is not a nightmare per se, but a recurring dream about a kiln that doesn’t exist. It is a large single chamber, with white interior, and there are shelves on the walls and in the center of the large chamber on a sort of island. The floor, walls, and island are all white and rough with kiln wash. There is no chimney, and the kiln is connected to the fire box via an elevated brick tunnel, which goes out the rear of the chamber about 2 meters, turns 90 degrees right, stretches about 8 meters, then takes another 90 degree right turn, where extends forward and turns into the firebox. From the firebox to the kiln forms a large U shape. Even more strange, the firebox is open to the sky and steps up to the flue channel, which somehow ‘sucks’ in the heat of the fire. The firebox is probably 4 meters long/deep, and the wood used is huge: entire tree trunks shoved in and stacked in a criss cross pattern, burning.  Any one have a kiln that looks like this?

Coming up to this fall firing in Oct., I feel as though everything is under control, and no particularly strong feelings of anxiety, yet the dreams continue, including 2 nights in a row now, a dream of some of my teeth falling out. Seems quite normal in the dream at least…

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.

New Videos

I finally sat down and figured out how to use my video camera and software. For anyone who is interested, here are some videos I posted to youtube.

Karatsu Sake Cups

Sake Cup Trimming Part 1

Sake Cup Trimming Part 2

Karatsu Teabowls

Karatsu Teabowl Trimming

All of these pots were made with clay from the property, discovered right under where we built the kiln. It has a lot of iron, but still takes some heat, and won’t bloat at higher temps. Probably due in part to the fact that it is very open with a lot of sand and other even larger inclusions. Even vitrified, it still sweats because of the openness. With use, the sweating stops, as all the pores fill with minerals from the water and tea tannins, etc…

Postfire thoughts

Well, time to sit down with the last firing and figure out what went wrong, and what went right.

Firing and packing: Great. With this firing I figured out, FINALLY, the proper exit flue volume to use. And with it, the proper packing procedure. The kiln climbed steadily, without effort, for 45 hours and the flame in the front chamber reached front to back really nicely. It turned out to be a fairly even gradient from front to back, from cone 13 in front, to a good melted 8 in back. No sidestoking necessary.
I am going to go back to using a pyrometer for the next firing, because this firing got very reduced. I think the stoke intervals were too close, and a pyrometer may help me get a better idea of temp climb timing, and when each cycle goes into oxidation.
At one point, when we switched to stoking the 2nd chamber, the temp just started dropping. You could tell from the sound and color of the kiln. I jabbed a pyro into a peep hole and it told me right away that I was stoking to frequently. After the flame had receded into the chimney and peepholes, and the roar had died away was when the temp really started climbing in the chamber. I had been stoking when the flames receded and the kiln quieted down, but once I started waiting rather for the temp to start dropping after the rise, the kiln got back on track. This rise took longer than I imagined, sometimes up to 10 minutes. Had been stoking waaayyyyyy too much.
This firing was a watershed moment for me, regarding packing, air, and stoking. I think next time will finally be the load that makes us all smile.

Glazes: Glazed ware in the second chamber turned out really nice. Reduction was still too heavy, but we got nice surfaces. Still, I won’t aim for that in the future. Madara glazes were too yellow for my taste. The first chamber glazes were so reduced that whatever their intended color, everything turned out a semi matte green, from the excessive iron pulled from the body saturating the glaze and crystallizing. I think the stoking interval will fix this problem.

Clay body: Oops. Here is where the shit hit the fan. Too much iron, especially considering the temp and amount of reduction that happened. The clay I used for the large pieces has too much iron for that type of firing environment, which is why they almost all collapsed. Having worked with a gas kiln for so long, it is hard to get out of the mindset of adding iron rich clay to other whiter bodies in order to get a desired color. The white clays in this area have enough iron for good color in a wood kiln. I keep forgetting that, but perhaps the shock of this latest meltdown, and the subsequent pain of shelf grinding will serve to jog my memory whenever I’m mixing clay for the wood kiln.

We got this off the shelf in one piece! The attached cup sits level when you set the piece on a table, so great for sashimi and  sauce or condiments.
We got this off the shelf in one piece! The attached cup sits level when you set the piece on a table, so great for sashimi and sauce or condiments.
The Fall of Icarus
The Fall of Icarus
Arm detail
Arm detail