the japanese potters...

.... are really great.  i am having such a great time just being in their presence and seeing so many similarities and differences in the way they work with clay. more later.

morning time... need to loosen the grip

I'm  drinking tea and eating cereal at the kitchen table this morning, and I realize how much the morning pages that I wrote so diligently at the beginning of this year helped my life and creativity.  I've been slacking on them, and feeling more and more overwhelmed by life.  I've given myself a deadline to fire sometime in december.... Every deadline I've put on myself and the kiln project in the past I have betrayed.

Also, this project is vitally important to me.  It isn't just a job that i can escape from afterhours...  It is my life's work, and in the years that this project has been underway many emotions and expectations have clung to this hulk of a thing. 

This weekend we began grate bars for the fireboxes.  They will be made of castable, as well.  I'm gearing up to help my friend Susie Bowman host some japanese potters for the week.  She met them last year in Echizen.  They have never done a soda firing or been to the united states, so it should be a fun and interesting week - if not a little stressful. 

My camera is broken and sent back to nikon for repair, hence the no photos being posted lately. 

exhale.....

kaolin, lovely kaolin

lovely kaolin mine. 

third day of kiln shelf casting...

I'll get some photos soon....

I'm on the tthrid day of working on kiln shelf casting.  My hands feel like they are vibrated off of my arms, and my arms are like tightly braided steel cables: Working with the conctrete vibrator is hardcore stuff, especially trying to man-handle the kind of control that these small castings require...

Also, I think I may have figured out the vibrator technique a little better and I hope that I didn't leave too much air in the first shelves I cast!  I hate not knowing about such a crucial thing...

the chimney blocks

So check it out, these blocks are precast from an alumina and silicon carbide castable which includes stainless steel fibers.  Complete overkill for the chimney, but it is the material with which I had to work.  I still have tons of these too.  I'm thinking of building another kiln using them for the bulk of the construction.  They are, however,  very, very, very heavy. The blocks were originally designed to be installed in the cooling chamber of a lime kiln.  They are called "cooler tiles" which makes them sound kind of breezy and quaint.  Let me tell you, they are neither breezy nor quaint.

HESITATION ABOUT CASTING SHELVES

Okay, I'm procrastinating... I've been looking over the research article and found out that the alumina based castable they used was only 8 percent silica.... the rest was fused alumina or various sizes.  My castables all have close to 30% silica.  Hopefully, this won't be an issue at 2300-2400 degrees F, and may actually help with mullite formation at those temps.  The norwegian folks were testing at higher temps mostly. 

today's work - kiln shelves out of castable

Man, I searched the web over and under for some refererence to building kiln shelves out of refractory castable and I finally (after months of searching) came up with this research article (norwegian microsilica company experiment).  These guys make a synthetic micro silica that apparently helps create the best mullite matrixes ever.  They are really pumped about what they do, and I got really pumped when I finally found validation for my assumptions. 

Today I put together forms for these  castable kiln shelves - tomorrow I cast them. All of them are 18 inches wide and 36 or 30 inches long, and last ut not least 1 3/4 inches thick.  I rented a concrete vibrator to bring the material into the tightest possible relationship -  a relationship that will hopefully foster a fecund grove of mullite crystals.   I'll hopefully post photos after tomorrow.

lately...

Here we go...  the scene couple of weeks ago.

Notice the card board sheet on top of the mixer to keep down dust.  Also, a mixer like this is essential for mixing the industrial castable - ESSENTIAL.  I can't emphasize it enough.  So many problems with the material and so much pain and time could have been minimized by using this mixer throughout the whole building process. 

This roller ramp also came in really handy for getting the trays of castable up to the working area. 

This is the insulating layer - a mix of sawdust, sandy fill dirt, and concrete mix.  We applied over the castable with fencing wire reinforcement.  It was so refreshing to use this mix after dealing with the thixotropic craziness of the castable. 

This is looking up over the side door, over the swelling flue chamber, and onto the giant block chimney... those blocks.... details in another post.

Purple Bricks? I want them!

Does anyone know why this happens?  It seems to only happen on really heavily reduced alumina washed bricks.  It is still one of those mysteries of the kiln for me, but i'm sure someone out there has done some research or has a good guess.  These bricks are from the montevallo anagama, "Fat Bastard", which i think is dimensionally exactly the same as Jack Troy's big anagama - the one in his book, "Wood-Fired Stoneware and Porcelain." 

local clays

I use a lot of local clay and am will probably write about it lot...

I live in a really clay rich area on the eastern shore of Mobile Bay.  There are so many exposed deposits of usable clay that really need little more than wedging to be a passable working body. In the 1800's there were dozens of kilns dotting the beaches and bluffs along the wooded shore where the clay banks tumbled into the water and were cut cleanly by spring fed streams. 

There are quite a few different working and firing qualities to our local clay, but the one common thread is that they are all unusually high in silica.  This is normally not a problem and most clays do really well without any additives.  However, I have run into problems with spalling and dunting with one very tight and white clay (with ocher and rosy iron marbling) from a west mobile mine.  I now add about 10 percent felspar and a little ball clay to most of the local clays to help bring some of that cristobalite into a less dangerous form of silica. 

thanks john

"This blog is also about the complete and total gnarly epicness of anagama kiln construction.

I will continue to follow your updates.

John B"

John helped me mix the ill-fated first arch. He is a great person and I am so honered to have had his help on this most epic and gnarly of projects.

Blocks, buttressing, and refractory castable

These shots are from January of 2008 and show the butressing and blockwork around the all castable kiln chamber. Chuck Smith and his recently and tragically deceased friend Mike along wih a crew of mexicans did this great work. Though, they should not have done the same courses on everything - a couple of the corners cracked badly when we back filled with dirt.





The blocks surround my kiln built entirely of refractory castables given to me by the great folks at a local refractory construction company. Among the refractories used: Pnuecrete 60, Resco's Lo Abrade, Express 30, Online 60, Versagun 60, and narcon 65. I've learned a whole lot about refractory castables through trial and much error. The original arch had to be torn down due to improper (by-hand) mixing of the low cement castables. The new arch is better than ever and incorporates some cool little scoops that we call "inferno-foils". They may or may not do what we want - What we want is a redirecting of flames, heat, and ash. In many tunnel and anagama kilns I have seen, especially tall ones, the heat rises to the top of the arch and shoots to the chimney while leaving the work at the bottom of the kiln bereft of heat and ash and essentially dead. Many people stack their kilns tighter at the top and looser at the bottom to compensate for this characteristic (and I'll probably do the same), but I hope my little inferno-foils, which you'll see later in photos, will help break up the flame and maybe create some neat spots for work.

first post

My kiln is approaching it's completion. It's been a long six or seven years in the making and this blog will be a focused way to share it's building progress, loading, firing, and finished results with you. There is a lot of catching up to do, alot of history to recount, to bring us up to the present state of anagama progress and artistic development.