Forms of the Formless Ceramic : March 2011

Saturday, April 30, 2011

March 2011

Gazuntite 3-11-1 Swan 3-11-2

Hermes 3-11-3 Ballet 3-11-4

Blues 3-11-5

No comments:

Exhibitions

-Mt. Rushmore, Cherubim, Red Wall Limestone, Cheops @ Watershed Review Fall 2023 -Pit Pony, Tortoise and Red Flower @ Animal, Vegetable, Mineral: Sein und Werden Summer 2023. -Reservations Please@Neon Garden Winter 2022 https://sites.google.com/view/neongarden10/ae-reiff?authuser=1 -Little Bird Pecking @ Fish Food Mag Fall 2019--Condominium. AZ State Fair 2019 https://animalwilderness.blogspot.com/2019/03/cement-blocks.html Flight and Flower @ AZ State Fair 2018 Plice (These Are the Eyes). Cover, Blinders Journal. Winter 2016
Hands Up. AZ State Fair 2016. 2nd place Free Standing Sculpture
Praise Jars. Cover, Buffalo Almanac. # 9. Sept 2015
Bus Stop. AZ Clay at WHAM. May 4-May 28, 2015
Flower From the Rock. Shemer Art Museum, Force of Nature. May 7th – June 18th, 2015.
Quechua Wife, Husband, Heart, Untitled, Herberger Theater Center, Crumpled, Dented and Crushed. January 9-March 15 2015.
Eleusis, Praise Him, Herberger Theatre Center Jan 2014.
Dharma Bum AZ State Fair, 2nd sculpture, Fall 2013.
Anti, Cover Aug 2013 .
Praise Him, Christmas Turkey, Flight All AZ Clay, March 2013
Corn, Rice, Bean Jar, Herberger Theater Center, Jan 2013
Looking for Work AZ State Fair 1st sculpture, Fall 2012
Boxcar Named Desire, Herberger Theater Center, Fall, 2012
Pit Pony, Mortal, Out of Body Herberger Theater Center, Spg
Balzac, All AZ Clay, Spg 2012
Rex, Portrait, Raven, Subliminal Interiors, Sept 2011
Geronimo, Chuang Tzu, Herberger Theater Center, Summer 2011
Balzac, Sein und Werden, July 2011
Ikon, Orion Headless, Feb 2011
Gypsy Art Show, Feb 2011
Mortal, Out of Body, Mask, Mad Hatter's Review, Winter 2011
Gypsy Art Show, Feb 2011

Water jars, boots, bags, faces, figures, animals, wall hangings.

Aesthetics

Sculpture in the folk tradition is a tale from Aesop. Beth Cavener Stichter likes to slice the image in planes from blocks, hollow out the center, carve and put it back together. Here is a pic of her, on her back with her bare foot upholding the belly of a horse [Belly (4)] So sexy. The mammals here are made from single planes combined, sheets rolled and thrown to catch the air. Shapes occur as the clay shows. Simplistic - no model, sketch, armature - parts attach with clay on a board with a knife. They come up from below, the four foot easier than the two. Laminates of porcelain impasto fired at a hot cone 10 show bisque in the crotch. Repeat not knowing. Make no notes. They crumple accordingly and make badger, stand up and make Pegasus. Either the clay reveals what the eye sees or it has to be rolled out again. Pony came from a third roll. A pair of boots made Sumu, Balzac, Black Eyed Pea.

Some potters, like Malcolm Davis, feel the clay chooses: "I first touched clay at age 40," he says, "and knew immediately that I had been a potter all along."

The Call and Response of Clay

"Making my mark on the raw clay and not having it perceived as contrived is a major anxiety of mine...I make every attempt to rise above 'technique only'...it is much more important to reveal your passion and character, not just your dexterity." Peter Callas, "Conversations," Claytimes, May/June 2009.

"What I have noticed in the poetry and poetics of the most important poets is that they are arguing, weaving, and composing a cosmology and an epistemology. Over and over again...It is this structuring, large and deep in the nature of things, that still thrills us in Hesiod’s struggle for the sense of it... repeatedly in the history of poetry, we find ourselves returning to epic structures and the bases of epic in the shape, size and feel of the world cosmos, I suggest that great poetry is always after the world--it is a spiritual chase--and that it has never been, in the old, out worn sense, simply subjective or personal.

"The Violets," Robin Blaser

"It was clear to me that if my scientifically reasoned working assumptions were correct and if I did my part in successfully initiating, and following-through on realizing the previously recited potential chain-reactive events, I would be supported by God in realistic, natural, but almost always utterly surprising-to-me ways. I therefore committed myself to such initiations, realizations, and followings-through."

Guinea Pig B," R. Buckminster Fuller, Inventions, xv.

"The proper life of a flexible instrument cannot be well ordered. It has to be terribly free. And utterly responsive to a darkly, dimly understood command" (18)..."a few brush strokes...not a representation of anything, but rather it is the subject itself"(40), "collaborations with some force or shaper of outcomes other than himelf." Thomas Merton in Angelic Mistakes. GoodReads.

I was at the library and stumbled on Merton's inks after completing some b/w monotypes. He printed from scrap paper with the pressure of his hand (36), made "drawings for us by dipping weeds in ink and slapping them onto a sheet of typing paper."

His aesthetic suggests some principles:

1) Something is made of nothing.
2) Never imitate yourself.
3) Respond to the dimly heard, trust it and it gets stronger.
4) The only horizon is within.

"Gabriel Marcel says that the artist who labors to produce effects for which he is well known is unfaithful to himself" (41).

"The images are not 'mine' nor are they those of a particular artist." "...aerated and porous, with the potential for velvety textures and minute, vanishing detail (41).

"The proper life of a flexible instrument cannot be well ordered. It has to be terribly free. And utterly responsive to a darkly, dimly understood command" (18).

His translation of The Way of Chuang Tzu (1965) says he "knows where he is going, but is not 'sure of his way,' he just knows by going there. He does not see the way beforehand, and when he arrives he arrives. His arrivals are usually departures from anything that resembles a 'way' (33).

Merton calls self-emptying, vanishing "a few brush strokes...not a representation of anything, but rather it is the subject itself"(40), "collaborations with some force or shaper of outcomes other than himself."

So "the perfect act is empty," "the images are... signatures of someone who is not around" (42,3). It takes more of this wine to mature in the barrel than the impatience to drink.

They "aren't drawings to be shown to anyone. They are purely personal, and therefore illegible hieroglyphs...my figures have no proper spatial proportion. They have no horizon of their own. The perspective of the shapes I try to capture lies outside the paper, at the other unsharpened end of my pencil--in myself." Franz Kafka

Like Kafka says of his drawings, they "aren't drawings to be shown to anyone. They are purely personal, and therefore illegible hieroglyphs...my figures have no proper spatial proportion. They have no horizon of their own. The perspective of the shapes I try to capture lies outside the paper, at the other unsharpened end of my pencil--in myself" (Claude Gandleman,(http://www.springerlink.com/content/j341274643x4024p/).

Ousmane Sow has always sculpted without a model. He creates his own medium. In a form of subtle alchemy, he allows a number of ingredients to macerate over the years. For him this medium is a work in itself, giving him almost as much pleasure as creating the sculpture itself. He applies this material onto a framework of metal, straw and jute, allowing Nature and the medium their own freedom thus opening of the door to the unforeseen.

Has anyone ever asked, "What painting ought he to make?" It is clearly understood that there is no definite painting to be made, that the artist is engaged in the making of his painting, and that the painting to be made is precisely the painting he will have made. It is clearly understood that there are no a priori aesthetic values, but that there are values which appear subsequently in the coherence of the painting, in the correspondence between what the artist intended and the result. Nobody can tell what the painting of tomorrow will be like. Painting can be judged only after it has once been made. What connection does that have with ethics? We are in the same creative situation. We never say that a work of art is arbitrary. When we speak of a canvas of Picasso, we never say that it is arbitrary; we understand quite well that he was making himself what he is at the very time he was painting, that the ensemble of his work is embodied in his life. Existentialism

ANGEL

This is a brush and ink composition in a series of faces, shapes and Bodies that emerge from accident and design by substraction from an inked plate. I was photographing this after it was framed near a window. The glass of the frame reflected the window and It looked like the figure of the angel was transparent and flying down the street.

II.

The Call and Response of Clay

Guinea Pig B," R. Buckminster Fuller, Inventions, xv.

"The proper life of a flexible instrument cannot be well ordered. It has to be terribly free. And utterly responsive to a darkly, dimly understood command" (18)..."a few brush strokes...not a representation of anything, but rather it is the subject itself"(40), "collaborations with some force or shaper of outcomes other than himself." Thomas Merton in Angelic Mistakes. GoodReads.

Has anyone ever asked, "What painting ought he to make?" It is clearly understood that there is no definite painting to be made, that the artist is engaged in the making of his painting, and that the painting to be made is precisely the painting he will have made. It is clearly understood that there are no a priori aesthetic values, but that there are values which appear subsequently in the coherence of the painting, in the correspondence between what the artist intended and the result. Nobody can tell what the painting of tomorrow will be like. Painting can be judged only after it has once been made. What connection does that have with ethics? We are in the same creative situation. We never say that a work of art is arbitrary. When we speak of a canvas of Picasso, we never say that it is arbitrary; we understand quite well that he was making himself what he is at the very time he was painting, that the ensemble of his work is embodied in his life. Existentialism

I was at the library and stumbled on Merton's inks after completing some b/w monotypes. He printed from scrap paper with the pressure of his hand (36), made "drawings for us by dipping weeds in ink and slapping them onto a sheet of typing paper."

His aesthetic suggests some principles:

1) Something is made of nothing.
2) Never imitiate yourself. Never urinate on yourself
3) Respond to the dimly heard, trust it and it gets stronger.
4) The only horizon is within.

"Gabriel Marcel says that the artist who labors to produce effects for which he is well known is unfaithful to himself" (41).

"The images are not 'mine' nor are they those of a particular artist." "...aerated and porous, with the potential for velvety textures and minute, vanishing detail (41).

"The proper life of a flexible instrument cannot be well ordered. It has to be terribly free. And utterly responsive to a darkly, dimly understood command" (18).

His translation of The Way of Chuang Tzu (1965) says he "knows where he is going, but is not 'sure of his way,' he just knows by going there. He does not see the way beforehand, and when he arrives he arrives. His arrivals are usually departures from anything that resembles a 'way' (33).

Merton calls self-emptying, vanishing "a few brush strokes...not a representation of anything, but rather it is the subject itself"(40), "collaborations with some force or shaper of outcomes other than himself."

So "the perfect act is empty," "the images are... signatures of someone who is not around" (42,3). It takes more of this wine to mature in the barrel than the impatience to drink.

Like Kafka says of his drawings, they "aren't drawings to be shown to anyone. They are purely personal, and therefore illegible hieroglyphs...my figures have no proper spatial proportion. They have no horizon of their own. The perspective of the shapes I try to capture lies outside the paper, at the other unsharpened end of my pencil--in myself" (Claude Gandleman,(http://www.springerlink.com/content/j341274643x4024p/).

ANGEL

Ceramic Experiments

Bisque banned. Roll mix of clays over porcelain over paper, sprinkle cobalt carbonate, oxide w/ gerstley borate and frit, edged w/ feldspar, blind stamp, edge with cedar shim impressions, set up around large PVC pipe, remove pipe, make shell. Dry, but the oxides flake off in bisque shelf, even after fixer, get banned from the bisque. Alt wedge oxides into clay.

Feldspars occur in glaze recipes probably more than any other ingredient. The reason is, Spars satisfy all the categories found in the Seger Formula which describes the molecular ratio of a fired glaze. Putting this another way, Spars provide flux, amphoterics (alumina), and silica to glazes. This is basically all you need. You could glaze a pot with Custer Feldspar and it would be pretty durable, but it would craze from an abundance of potash(potassium). If you wanted a high fire tenmoku or celedon, you could make these with potashspar, whiting, kaolin or ball clay, and silica. Feldsparwould be the major percentage in the receipe.
Very useful stuff to potters and glazemakers. I still have two unopened bags of the old Kingman Potash Spar. Craig Martell

...feldspars are among the few relatively insoluble sources of potash, soda, and lithia.

Glass Formers

Ceramic colorants

'Ceramic colorants' are added to a glaze or a clay to create color. Carbonates and oxides of certain metals, characterize most colorants including the commonly used cobalt carbonate, cobalt oxide, chrome oxide, red iron oxide, and copper carbonate. These colorants can create a multitude of colors depending on other materials they interact with and to which temperature and in which atmosphere they are fired.

[hide]

[edit] Cobalt

Cobalt is commonly used in either its carbonate (CoCO₃) or its oxide (Co₃O₄) forms. In the presence of most fluxes, it yields blue colors ranging from low saturation pastels to high saturation midnight blues in both oxidation and reduction atmospheres. However, in the presence of magnesium, cobalt can become purple, pink or reddish blue depending on whether it was fired in oxidation (yields purple) or reduction. Cobalt is also commonly used in black glazes and in washes as decorative medium. Common saturation percentages for low saturation range from (.25 to .5%) and in high saturation from (1 to 2%).

[edit] Chrome

"Chrome is a rather versatile and fickle colorant," (Chappell). Chrome oxide (Cr₂O₃) is commonly used for achieving greens. However, in the presence of zinc, chrome can produce brown. Glazes with tin oxide present will often blush to pink if fumed with chrome or if chrome is present in the glaze with the tin, often intense pinks occur. If fired above cone ^6, chrome will fume and become a gas in the kiln. Common saturation percentages for chrome at low saturation range from (.25 to .5%) and at higher percentages from (1 to 2%). Chrome is a refractory.

[edit] Red Iron

Iron is commonly used as a colorant in its red iron oxide form as (Fe₂O₃). Red iron oxide is commonly used to produce earthy reds and browns. It is the metal responsible for making earthenwares red. Iron is also another tricky colorant because of its ability to yield different colors under different circumstances. At low percentages (.5-1%) and in the presence of potassium, iron will become light blue or light blue-green in reduction (as is seen in traditional celadons). In the presence of barium, iron may become yellow green. When used in combination with calcium, red iron oxide can become pale yellow or amber in oxidation or green in reduction. Common percentages for red iron oxide range from (4 up to 10%).

[edit] Copper

Copper's carbonate form (CuCO₃) is commonly used to produce greens, turquoise, and copper reds. If need be, copper oxide (CuO) can be substituted but has a larger particle size and glazes should be adjusted to generally half the amount called for. In barium based glazes greenish blues often result from copper. Alkaline feldspar glazes with copper fired in reduction atmospheres will often yield ox blood or copper red glazes discovered by the Chinese. When fired above cone ^8 copper can become unstable and will often fume off of a glaze in vapor form.

Glaze colors

From about 1615, the Dutch potters began to coat their pots completely in white tin glaze instead of covering only the painting surface and coating the rest with clear glaze. They then began to cover the tin-glaze with clear glaze, which gave depth to the fired surface and smoothness to cobalt blues, ultimately creating a good resemblance to porcelain

Appreciation of Li

Call and Response of Clay. Say something spiritual about clay. It has to rest after work.

These are photographs of pots. Some don't have bottoms,
some don't have tops. Clay dialogues like a poet:

"I knew him once char wood
with a brush, grain patterns
of wood with a torch,
raise relief, drop stone from a height,
make dragon fly, spider web, tree."

So shape, reshape, work, non work,
poured on plywood like paint,
asks a clay crust of clay, who writes?

"Li patterns mark jade,
wood in water, fire in matter,
cloud mist spit, tree ink,
brush plunge, elbows heads (Duthuit).
Wind is greater than water, he said
to a potter as clay, scored glass
paint flood, stone build. "

Chuang-tzu said this nature was born on dry land and grew up in water. Chuang-tzu said, "though seventy years of age I am still making wheels." Do not repeat.

Creation

Kintsugi (金継ぎ) (Japanese: golden joinery) or Kintsukuroi (金繕い) (Japanese: golden repair) is the Japanese art of fixing broken pottery with lacquer resin dusted or mixed with powdered gold, silver, or platinum a method similar to the maki-e technique. As a philosophy it speaks to breakage and repair becoming part of the history of an object, rather than something to disguise.

Lacquerware is a longstanding tradition in Japan, at some point it may have been combined with maki-e as a replacement for other ceramic repair techniques. One theory is kintsugi may have originated when Japanese shogun Ashikaga Yoshimasa sent a damaged Chinese tea bowl back to China for repairs in the late 15th century. When it was returned, repaired with ugly metal staples, it may have prompted Japanese craftsmen to look for a more aesthetic means of repair. Collectors became so enamored of the new art that some were accused of deliberately smashing valuable pottery so it could be repaired with the gold seams of kintsugi. Kintsugi became closely associated with ceramic vessels used for chanoyu (Japanese tea ceremony). While the process is associated with Japanese craftsmen the technique was applied to ceramic pieces of other origins.

Below are 40 different things to try with shino. Part of this list was originally published in Studio Potter magazine in 2003. People have been experimenting and adding to it ever since.

1. Rather than mix each batch fresh, add 1/2 batch when old batch is 1/2 gone;
2. Use wax resist or shellack to cover parts of a pot;
3. Use plastic wrap to cover parts of a pot;
4. Place glazed ware in dry sawdust, perforated bags, bubble-wrap, textured paper, or packing peanuts to influence patterning caused by drying;
5. Stack glazed pots to dry;
6. Dry glazed pots touching one another or crowded together;
7. Dry with coils of wet clay, shells, etc. on flat surfaces;
8. Apply wax with foam stamps, splatter on with fingers, trail with slip trailer;
9. Splatter water on surface of glazed pots with fingers or tooth brush;
10. Spray soda ash solution on glazed pots;
11. Sprinkle wood ash (or mix of wood ash and soda ash) on freshly-glazed pot;
12. Dry open pots upside down;
13. Dry pots in front of heater or fan or repeatedly mist/spritz with water;
14. Bury in wood chips;
15. For luster, brush/spray high-iron glaze over;
16. Try saggars – or build up around pots with hard bricks/broken shelves;
17. Add some common salt/kosher salt/rock salt;
18. Substitute different feldspars, kaolins, spodumenes, ball clays;
19. Re-fire to biscuit temperature in electric kiln (cone 06);
20. Vary the percentage of soda ash (from 0% to 20%);
21. Substitute amblygonite for ceramic-grade spodumene; it has lower thermal expansion and higher phosphorus content;

22. Soak biscuit in soda ash solution;
23. Test over iron and iron/manganese washes;
24. Fire test tile dipped in copper-red right next to Shino pot; spritz copper-red glaze over glazed pots before firing; or try adding copper carbonate to the Shino glaze;
25. Dampen/spritz areas of biscuit with water or damp sponge before glazing;
26. Aim heat gun or hair dryer across ware board of freshly glazed Shino pots;
27. Spray hair spray over glazed pot;
28. Use thin wash of temmoku glaze or a gunmetal glaze (containing manganese) over a Shino-glazed pot;
29. Try spraying Shino glaze, varying placement, overlap, vary density;
30. Apply soda ash or wood directly on pot after glazing; spray first with spray adhesive if pot is too dry for ash to stick;
31. Spatter iron oxide wash over freshly-glazed pot with toothbrush;
32. Try thin washes of ocher, manganese or copper carbonate;
33. Sgraffito – scratch through pattern on shino glaze.
34. Place your pot in the freezer for an hour before glazing
35. Stuff plastic wrap inside your vessel for a few days while the glaze is drying and salt crystals are forming
36. Use blue masking tape or damp strips of newspaper on top of a freshly glazed pot to influence drying irregularity. Remove tape before firing :- )
37. Use underglazes to paint designs on bisque before glazing
38. Rub black underglaze or red iron oxide wash into textures of your clay before glazing
39. Apply the glaze thinly over recently washed bisque, then re-dip/re-spray two or three days later
40. Mix two different shinos together in a spray bottle container and spray your bisque. Try a 50/50 blend to start.
41. Use your finger to run lines and patterns through the salt crystals that form on the surface of a dry glazed pot.

Metal	Melting Point
Metal	(^oC)	(^oF)
Admiralty Brass	900 - 940	1650 - 1720
Aluminum	660	1220
Aluminum Alloy	463 - 671	865 - 1240
Aluminum Bronze	600 - 655	1190 - 1215
Antimony	630	1170
Babbitt	249	480
Beryllium	1285	2345
Beryllium Copper	865 - 955	1587 - 1750
Bismuth	271.4	520.5
Brass, Red	1000	1832
Brass, Yellow	930	1710
Cadmium	321	610
Chromium	1860	3380
Cobalt	1495	2723
Copper	1084	1983
Cupronickel	1170 - 1240	2140 - 2260
Gold, 24K Pure	1063	1945
Hastelloy C	1320 - 1350	2410 - 2460
Inconel	1390 - 1425	2540 - 2600
Incoloy	1390 - 1425	2540 - 2600
Iridium	2450	4440
Iron, Wrought	1482 - 1593	2700 - 2900
Iron, Gray Cast	1127 - 1204	2060 - 2200
Iron, Ductile	1149	2100
Lead	327.5	621
Magnesium	650	1200
Magnesium Alloy	349 - 649	660 - 1200
Manganese	1244	2271
Manganese bronze	865 - 890	1590 - 1630
Mercury	-38.86	-37.95
Molybdenum	2620	4750
Monel	1300 - 1350	2370 - 2460
Nickel	1453	2647
Niobium (Columbium)	2470	4473
Osmium	3025	5477
Palladium	1555	2831
Phosphorus	44	111
Platinum	1770	3220
Plutonium	640	1180
Potassium	63.3	146
Red Brass	990 - 1025	1810 - 1880
Rhenium	3186	5767
Rhodium	1965	3569
Ruthenium	2482	4500
Selenium	217	423
Silicon	1411	2572
Silver, Coin	879	1615
Silver, Pure	961	1761
Silver, Sterling	893	1640
Sodium	97.83	208
Steel, Carbon	1425 - 1540	2600 - 2800
Steel, Stainless	1510	2750
Tantalum	2980	5400
Thorium	1750	3180
Tin	232	449.4
Titanium	1670	3040
Tungsten	3400	6150
Uranium	1132	2070
Vanadium	1900	3450
Yellow Brass	905 - 932	1660 - 1710
Zinc	419.5	787
Zirconium	1854	3369

Wood Firing in 29 Palms

Steve Davis, Jamie Boran, Jonathan Cross, & Kaz Ota firing the Firebox Kiln

Click here to view the Firebox Kiln page

Jonathan Cross has put together a firing schedule shown below. PDF Version

Firing the “Fire Box” kiln

Day 1-2 – Preheat with propane burner. 6-12 hours

Day 2-3 – Preheat kiln with wood. 24 hours

Day 3-5 – Firing work. 24-72 hours

Day 6 – Down firing / Reduction Cool (Optional) 6-12 hours

Wood 2-5 Cords of wood depending on the length of firing and ash desired.

Firing Schedule

All work should be bisqued so that the preheating can proceed more rapidly. You still want to take time to preheat the kiln properly. The method for preheating that I use was introduced to me by Furutani Michio. His philosophy, which I can attest to from experience, is to fire the kiln first, then the work. This simply means you need to take a day to preheat the kiln and all of the kiln furniture so that you are not using up energy later in the firing.

I start with a propane burner in the front of the kiln over night. Simply open one of the primary airports and set the burner up inside, adjusting the flame so that it is not directly hitting any of the work. Secure the burner so that it cannot easily be knocked out of the primary airport by a passing animal in the night. The damper is closed and all view ports are open to allow moisture / steam from wadding to escape the kiln. Preheating with the burner can be any where from 6-12 hours. This is done over night to give your self a good nights rest.

The following morning, remove the propane burner from the primary airport. Temperature should be around 350F. Attach a new tank of propane (I use 15 gallon barbecue tanks) to the propane burner and place it in the passive damper of the chimney. Much of this heat is lost, but preheating the chimney is advantageous in many ways. First, it gives you an immediate draft through the kiln and helps to heat the ware chamber more evenly in the beginning of the firing when temperature differences from front to back and top to bottom can be extreme. Second, the burner in the chimney burns a lot of carbon and smoke passing through the chimney making for a cleaner firing in the beginning. The damper is open while the burner is in the passive damper. All view ports are closed with a brick and sealed with clay.

A small chamber is built outside of two of the primary ports with kiln shelves and bricks. A small fire is lit with kindling in this chamber. Wood is continually fed into this chamber, gradually increasing the size and amount of wood per stoke while pushing coals into the firebox. This process should take about 24 hours, gradually raising the temperature from 350F to 1000F.

Around 1000F, the firebox is hot enough to start stoking through the side door. Wood tossed into the firebox should immediately catch fire. If not, continue stoking through primary airports until wood catches fire through door stoking. (Check every 100 degrees). During this time the propane for the burner in the chimney will run out. Remove the burner and replace the passive damper. Dampers should be set to 1/4 open or about 2 inches of outside length to keep in heat, but still allow flow. Once stoking begins through the door, open all primary ports half way and begin stoking with 2 pieces of wood. Stoking should proceed this way allowing for a peak in temperature (read on the digital pyrometer), followed by a sustained drop of 5 -10 degrees. The goal at this point is two fold, to increase temperature and to create a small bed of coals to maintain heat. This method is used all the way up to 1800F or when cone 08-010 is bending.

Now, its time to start the body reduction (optional). Adjust the dampers to 1 inch open and increase the amount of wood to 4 pieces per stoke. Primary airports should be sealed to 1 inch as well to decrease oxygen in kiln. Maintain smoke in the stack, stoking when flames or smoke clear the stack. Body reduction can take as long as 6 hours with cone 04 dropping during this time.

After body reduction, it is time to climb to high temperature. Many choices can be made at this point. Firstly, open the dampers and primary airports all the way. Begin stoking 2 pieces of wood, stoking five degrees below the highest observed temperature during a stoke. Continue this pattern until the highest temperature desired is reached. Maintain a healthy coal bed that is white-hot. Every hour or so, use a piece of steel pipe to agitate the coals and keep any dead coal areas from forming. Dead coals are dark inside the kiln and can create insulated, under-fired areas of work. When the peak temperature is reached, the dampers and primary airports need to be adjusted to half way. The amount of wood used per stoke, and when to stoke, needs to be adjusted to stall or maintain temperature. Increasing the amount of wood to 4 pieces and stoking at the desired temperature is a good rule of thumb. An example would be stoking 4 pieces, watching the temperature drop, and then waiting until it climbs back to 2350F, and then stoking 4 pieces of wood again. How long you soak the kiln at peak temperature is a matter of taste. I recommend at least 2 hours at peak temperature to melt ash.

After this period of peak firing is completed, its time to cool the kiln. There are 3 basic ways to go about cooling. First, is letting the kiln cool naturally and slowly by closing all dampers, primary airports, and cone viewing ports, and letting the kiln sit for about 4 days to cool. Second, is to crash cool the kiln down to 1800F -1450F degrees in oxidation. This method requires that the dampers, primary air ports, and stoke door remain open until the bottom temperature is reached. Third, is to cool the kiln in reduction. Seal the kiln up tightly by closing all ports and then sealing them with a wet clay/sand slurry. In a side stoke port, a 2” x 2” opening is used to stoke a 1” x 12” piece of wood at around every 10 minutes to keep the kiln in reduction as it cools down to any where from 1800-1450 degrees.

Forms of the Formless Ceramic

Saturday, April 30, 2011

March 2011

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