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kiln building -- explosions from the horse's mouth

updated mon 31 mar 97

 

Hiro Matsusaki on sun 9 mar 97

It takes practice. It takes practice to make good pots. Or, to succeed.

It takes practice, and a lot of work with clay. Dig, purchase, knead,
center, throw, trim, dry, bisque, glaze, fire, pack, promote, market,
collect, and make new plans for new lines or designs. The list goes on. It
takes practice.

Kiln building takes practice, as well. Unfortunately, pretty hard to
practice it as much as the other activities related to clay. Then there are
those who specialize in building of the kiln. Of one type or another. They
are for hire. And their skills are similar to engineers and trades people.
Specialized. So, before we ask the experts, we must know where we are
headed. This means we have to make a sort of basic plans. The experts are
not going to recommend competing designs, even if your needs would be better
served that way by a competing kiln builder. So many choices or kiln
building materials are available today. And potters want different things
all the time.

I talk about studio potter/artist situation. And not commercial production,
although I realize that the categories are not mutually exclusive. This is
to keep the discussion as straightforward as possible, and to meet with the
(perceived) need of an aspiring potter/artist as such (including myself).

Potters generally agree that the best kiln building book is the second
edition of The Kiln Book by Fred Olsen. His plans do work, and he covers a
wide range of subjects. For example, his fast fire wood kiln (I have had my
hands into building and firing one, so I know) is really fast fire and easy
to build. Although it may not mention, in great details, what kind of wood
and how it should be used, and what results it should give, that is asking
too much. One can experiment to find out and place posts here, so it is not
a big deal. Once, in woodfire, my tall nice pot came out cracked because of
sudden, repeated coolings of the kiln by ash thrown in to gain that effect.
It had been fired twice before, so my craftmanship was in no way to blame.
Mine was precariously placed close to the chimney and flue, due mainly to
its size, I guess, in a small woodfire kiln. Needless to say, no pots came
out with any ash results on that firing. I had known this, but how could I
stop it? No way. Stupidity tried once was acceptable. Not twice. This is
what I mean experiment. Try different things till you find the one you like.

Lack of practice on kiln building, however, means this. Many experienced
potters choose to build kilns from ground up. Some committee decision kilns
built this way literally exploded (fortunately I was not there when things
happened and no one was to blame. Remember? It was a committee decision.).
If they did not explode, often they stalled before reaching the temperature.
No harms done. Just redesign, or fire to the lower temperature. Lack of
temperature means no explosions. At any rate, these were beautifully
designed kilns from the ground zero or the first floor up. And approved and
constructed with loving care. But they exploded. The first time they were
fired. Why? They did not have time to make the ground solid or dry enough.
Typically, they had schedules to keep and fired before the natural aging of
the foundation and other structures. Higher temp didn't help, either.

Any water could be superheated and turned into steam. It can explode or
catapult dry-set firebricks flying all over, bringing the reinforced roof
down. Or, the foundation could melt and invite explosive air or steam leaks.
Nuclear powered aircraft carriers lauch those heavy jetplanes by steam, even
today, since it is so convenient, concentrated and powerful a source of
energy,

In contrast, natural gas is very safe. So is propane. My previous post on
the smell of gas is meant to be a warning. Natural gas companies, seeing a
good customer, are quite helpful in many ways to get you through the initial
ordeal of high investment. If you suspect a leak or damage a main, and call
them, sometimes two or three trucks and half a dozen people would show up in
a ziffy. (This actually happened to me. I'll spare you the minute details.)

First thing you notice after converting from electric to gas is that pots
often explode. Water in the pots does the same to your pots. Fortunately,
this has never happened to my pots, but I have seen other pots do it. (I
keep mine away from those suspected ones, if I can.) The warning of pot
explosion is like the danger of gas. It does not occur often, but the threat
is there, to let someone make a statement to that effect, and gain respect.
Once-firing is more susceptible to this, I guess, while poor shelving and
substitue posts would melt or deform .... ruining the pots as well. Don't
trust old posts or bricks. Their looks are deceiving. Especially at higher
cone range. For low fire, you don't need elaborate kilns anyway. Just pit
fire, sawdust, raku or what have you.

Practice. Practice. It takes practice. We all do this with clay. But not
with kiln building skills. There are so many things to consider that it is
practically not practical to practice kiln building. How do I do it? I
present my views and wish to share them with you, if I can. For now, I must
prepare my tax returns. But I can lead you to the water, at least, and it is
up to you to decide if you are going to drink it or not.

Seriously, if you are considering the kiln building, or have tried your hands
by converting electric to gas and raku, etc., the first thing to condier is
this.

For what ends do I wish to use this kiln? Not now, never, only in THREE (3)
years. Yes. Three years. Your plan should look toward that time span.
This will let you off the hook of the familiar chicken and eggs dilemma.

History repeats itself. What we practice today is basically the studio
artist tradition practiced 400 years ago by Ogata Kenzan (book available from
Potters Shop at special discount--you will note the design of food vessels
are just as fresh today as were four hundred years ago--the same clay, the
same glazes and firing methods) and kept alive till recently by Japanese
(functional by our terminology) potters. The teabowls and flowerpots are the
epitome. After looking at some Japanese pottery of similar period, you may
think Voulkos is vindicated, although the older (some may call medieval)
Japanese ones are more abstract or symbolic and less derivative (certainly
far better in texture, deforme or asymmetry -- they survived those bombings,
despite the pottery power intrigues involved -- and some potters still stick
to the tradition jealously). (I refrain from participating in the recent
debate, though. This is about kiln building.)

There, another tradition of sumo (wrestling match) still exist. Sumo is
getting internationalized now, as the spectator sport cum laude, but sumo is
where the strongest and the best gets to be at the top (the recent champion
was from Hawaii). The sumo and yakimono (literally, burned stuff, meaning
pottery) are the time machine relics that kept things still for that many
years. Very rare thing to observe and enjoy. Living things that took place
hundreds of years ago. Happening all over again today. No Darwinian
evolution or the survival of the fittest theory fit the time machine
perspective. Please don't be sidetracked by the imitation of Voulkos whcih
some may practice over there. I talk about the time machine pleasures to see
things as they happened nearly four hundred years ago. Japanese pottery is
preserved by the time machine! Today, there are so many things that compete
with the traditional pottery, like lacquered ware, wood vessels, plastics,
metals and so on that it is a small wonder the tradition survived. Sumo
likewise takes place on a national scale as an institution. It competes
against professional baseball, soccer (football European style), horse, boat
or bicycle racing.

In view of the competition and tradition, I say three years and not four
years for our kiln building time frame. That is less than one percent of the
time which kept the relics alive. We can be at least that patient, can't we?


The three years is a good benchmark. For two reasons. One is that you can
be a different potter that you wish to be in that many years. I'm not saying
that you wait for that many years to build one. No. I say that you make
your plan now, based on what you need in three years and not based on what
you want to do now (like making a bundle of dough or lots of pots which the
gas firing would let you do). It's no easy matter to see you for what you
can be in three years, realistically. Daydream your future, your plan
becomes a pipe dream.

Second, the kiln building is a large investment. In any business, the larger
the investment, the larger the returns or the money you can get out of it.
And conversely, the larger the expected revenue, the greater the risk and
uncertainties. All other things being equal, that is. The exception is
government sanctioned VLTs (video lottery terminals), where people push
bottoms on a five-wheel and contribute the tax revenue. The tidbits about
the clever scheme in Canada: Some provinces tapped this newer source of
revenue before the feds became wise. Cigarettes and alcohol were already
taken by the feds. Marihuana is yet to be decided on. Anyway the VLTs are
in bars all over the province, and not confined to those licensed casinos
which make private money as in many states where they are legal. Hence the
government maximizes the tax revenue generated. It is a monopoly in Alberta
and Ontario. B.C. has recently banned it. Still others are to start it,
saying that it is a simple amusement worth adding to the till for the
privilege. Imagine a long winter when no other entertainment exists in an
isolated rural community which you find in abundance in Alberta. This is far
more addictive than Free Cell! And it is not a free entertainment. What a
hoax! It is a new tax. Unfair, selective and predatory. There are a lot of
hidden costs, as well, like policing while-collar crimes of forged checks,
fraudulant claims, and so on, to finance the habit, or lost homes and broken
families, let alone tardiness or sick leaves accumulated. People are naive
enough to condier this a moral issue. People who gamble have weak morals and
weak will. That's the argument. Can you believe it? Actually, the twenty
years olds or the youngsters without much discretionary income are the
biggest losers. So, I say the government moral is wrong. I say no to such a
taxation scheme. And I have as much sympathy to the young as I have towards
the non-old potters, or new pottes, for that matter.

Back to the pottery business. The investment in kiln building entails both
risk and uncertainties. The risk is zero, if you have the dough and energy
to burn, now, and can sustain the pace for three years. The uncertainties
become zero, if you know you will be the number one (#1 or numero uno) potter
in three years, if not now. For the relatively small markets you envision.
Not the entire universe, mind you.

Three years, then. You can make some allowances for profesional diseases or
accidents (check appropriate web sites for toxic chemicals, wrist or elbow
pains, etc.). In three years, a lot of other things can happen, also,
things which are not under your direct control. People's tastes change. The
markets do change. The economic ups and downs aside, more competition would
get into the picture. I say facetiously that more new potters get into the
picture than old potters getting out (dying out, including me, hopefully not,
since the statistics are for me). Three years mean that much graduates from
the pottery programs, some of whom may have masters degrees and good
connections to the power to behold, and the charm of youth which the
collector deems dear. Others will hone up on their pottery making skills and
equipments. Things do not stand still for three years.

Studio potter/artist markets are highly competitive. Your pottery must
create, yes CREATE and serve (by the trade jargon what is termed as) the
NICHE market where you are the only one who can satisfy that market better
than anyone else, and that others find it hard to dislodge you from that
spot. To do this, you have to make things different and better. In every
way, including marketing.

The gas kiln is sure to make your pot different. The better? I don't know.

Gas fire can give you an edge over electric one. Cost is an obvious one.
But to be more specific, porcelain, woodfire and salt cannot be duplicated
by others, although imitations can be made. But these are not for everybody.
Strangely, some functional ware at high fire cannot compete against low or
medium fire in terms of production cost and aesthetics. The prospective
customers do not know better, for one. For another, a lot of people are
already in this type of market.

That told, though, there are less high fire stuff in the markets. If you
promote that well, you are in business. High fire stoneware, if made well,
are more durable, for instance. Many who can afford a cottage want ovenware
to go, to give you just one example.

Not many can throw well, or pull handles. Some are clumsy at decoration.
For that matter, many do not even sign their name at the bottom of the pot.
It is too time consuming. Whoa! Stamps are used, instead, with pride. I
think people would be impressed by nicely designed stamps, for sure. But if
everybody uses stamps, I would sign my pots, In Japanese. Or, Mongolian and
Hindukstani. That would certainly make my pots different. All I have to do
now is to make them better and a little different. Stamps connote
conformity, and my name or pottery now become non-conformist, different.
Better? Well, that is not decided yet. We are not talking about any legal
documents or commitments which Japanese style stamps suggest. By the way,
Hamada never signed his pots in later years. Nor used any stamps. I'll talk
about such things after my tax returns are completed, if the opportunity
arises.

Different and better. That's the catchword.

It should let you keep your monopolistic hands on the market for a long time.

HM