mel jacobson on mon 10 jul 06
it dawned on me coming back from ny that
kilns are just like rifles.
you have to sight them in before they work.
every one of them. and, it takes a great deal of
time to get the rifle to hit `dead center` every time.
then you have to learn to shoot.
often people buy a commercial gas kiln and think
that it should fire...`right out of the box`.
fuel kilns don't work that way.
like glazes, it is not so much about the recipe. (as john h. just
mentioned.) kilns and the location of the kiln, the wind,
the part of the country, the relative altitude all play a part
in firing a kiln. urban kilns with buildings around vs a kiln
in a rural area with no barriers...makes a difference.
the building you house the kiln in...makes a difference.
as clay body affects glaze, loading and shelf placement affects
firing. gas pressure up or down may totally affect a commercial
kiln. what is high pressure to one person, is low pressure to another.
i find over and over, that clean air, low gas fires faster than...
`hey wally turn that sucker up...let's get some gas flow
into that thing.` then watch the temp go down.
it was fun to be with harvey sadow and steve branfman. talk
kilns and burners...how kilns fire. and how the minds of
a few potters are changing, and the understanding of
how kilns work. old book theories that have become biblical
among potters are totally wrong. and the concept of
`simple, keep it simple` always works.
harvey and i laughed out loud when we both said the
word...`bagwall` at the same time.
we call them heat dams. keep the heat from the kiln chamber.
what are people protecting their pots from in a gas kiln?
`HEAT?`. WHEN A GAS KILN REACHES CONE 10, ALL THE of
KILN, SHELVES, BAG WALL AND POTS ARE AT CONE 10. that is
what is desired. some potters firing wood are taking the
bag wall down. it is not needed in almost every case. donovan
did not put a bag wall in our kiln. he installed a diamond shaped
flame deflector. it is six bricks in shape, about four bricks tall. it is
made to move flame, not stop it.
it is like 16 inch steps in a wood kiln. it just stops the heat
from moving back to the flue. (you see, they are pretending
they have a hill going up. silly.)
bang, hit a step, bang, hit a step. it is like putting a door
in the middle of the kiln. but, there was a plan in a book
in 1966 of a wood kiln...and everyone still uses it. of course
then wear japanese clothes, head bands with kanji...kiln
gods on top...and pretend you are at bizen.) good science always wins
the firing war.
i am becoming a fanatic on tight chimneys. as tight as
you can make them...i love the spiral pipe metal chimney,
with kaowool flue liners, welded together with itc. one
clean/perfect chimney...no leaks. same for wood fired kilns.
tight, full mortared brick. add a free brick for a passive damper,
but, not the entire stack.
it takes time to learn to shoot well. it takes time
and energy to learn to fire a kiln...learn how it acts,
what are the things that make it stall.
if you change from a .22 to a .308 many things change
in firing a rifle. same for firing a kiln.
if you think that a kiln god will make your kiln fire...boy,
do you have trouble ahead.
if you think it is fun and joyful to have a kiln god...and then
learn to fire your kiln within the attitude of good science
...then you will have great pots.
mel
i love the story of a friend that was in japan
watching a wood firing anagama. he went into
the potters studio and found a laptop with
leads running to the kiln. (under a towel.)
he asked the old potter about the computer..
the old guy said...`i am not a fool you know, this is
good science.`
from: mel/minnetonka.mn.usa
website: http://www.visi.com/~melpots/
Clayart page link: http://www.visi.com/~melpots/clayart.html
Overall's on mon 10 jul 06
You are so right Mel.
Since installing my kiln 11 months ago,
I've fired it 18 times now and still learning;
like what you recommended always.
Get a kiln, any kiln, learn to fire it.
Takes about a couple dozen times you said.
I don't know how I could begin to understand it
without my Fluke and Oxy.
Thank God for You Guys.
Try this, try that, don't do that ever again the same
way. It's a potter's secret dance with their kiln.
Kim in Houston
--- mel jacobson wrote:
> it dawned on me coming back from ny that
> kilns are just like rifles.
>
> you have to sight them in before they work.
> every one of them. and, it takes a great deal of
> time to get the rifle to hit `dead center` every
> time.
> then you have to learn to shoot.
>
> often people buy a commercial gas kiln and think
> that it should fire...`right out of the box`.
>
> fuel kilns don't work that way.
>
> like glazes, it is not so much about the recipe. (as
> john h. just
> mentioned.) kilns and the location of the kiln, the
> wind,
> the part of the country, the relative altitude all
> play a part
> in firing a kiln. urban kilns with buildings around
> vs a kiln
> in a rural area with no barriers...makes a
> difference.
> the building you house the kiln in...makes a
> difference.
>
> as clay body affects glaze, loading and shelf
> placement affects
> firing. gas pressure up or down may totally affect
> a commercial
> kiln. what is high pressure to one person, is low
> pressure to another.
>
> i find over and over, that clean air, low gas fires
> faster than...
> `hey wally turn that sucker up...let's get some gas
> flow
> into that thing.` then watch the temp go down.
>
> it was fun to be with harvey sadow and steve
> branfman. talk
> kilns and burners...how kilns fire. and how the
> minds of
> a few potters are changing, and the understanding of
> how kilns work. old book theories that have become
> biblical
> among potters are totally wrong. and the concept of
> `simple, keep it simple` always works.
>
> harvey and i laughed out loud when we both said the
> word...`bagwall` at the same time.
> we call them heat dams. keep the heat from the kiln
> chamber.
> what are people protecting their pots from in a gas
> kiln?
> `HEAT?`. WHEN A GAS KILN REACHES CONE 10, ALL THE
> of
> KILN, SHELVES, BAG WALL AND POTS ARE AT CONE 10.
> that is
> what is desired. some potters firing wood are
> taking the
> bag wall down. it is not needed in almost every
> case. donovan
> did not put a bag wall in our kiln. he installed a
> diamond shaped
> flame deflector. it is six bricks in shape, about
> four bricks tall. it is
> made to move flame, not stop it.
>
> it is like 16 inch steps in a wood kiln. it just
> stops the heat
> from moving back to the flue. (you see, they are
> pretending
> they have a hill going up. silly.)
> bang, hit a step, bang, hit a step. it is like
> putting a door
> in the middle of the kiln. but, there was a plan in
> a book
> in 1966 of a wood kiln...and everyone still uses it.
> of course
> then wear japanese clothes, head bands with
> kanji...kiln
> gods on top...and pretend you are at bizen.) good
> science always wins
> the firing war.
>
> i am becoming a fanatic on tight chimneys. as tight
> as
> you can make them...i love the spiral pipe metal
> chimney,
> with kaowool flue liners, welded together with itc.
> one
> clean/perfect chimney...no leaks. same for wood
> fired kilns.
> tight, full mortared brick. add a free brick for a
> passive damper,
> but, not the entire stack.
>
> it takes time to learn to shoot well. it takes time
> and energy to learn to fire a kiln...learn how it
> acts,
> what are the things that make it stall.
>
> if you change from a .22 to a .308 many things
> change
> in firing a rifle. same for firing a kiln.
>
> if you think that a kiln god will make your kiln
> fire...boy,
> do you have trouble ahead.
> if you think it is fun and joyful to have a kiln
> god...and then
> learn to fire your kiln within the attitude of good
> science
> ...then you will have great pots.
> mel
> i love the story of a friend that was in japan
> watching a wood firing anagama. he went into
> the potters studio and found a laptop with
> leads running to the kiln. (under a towel.)
> he asked the old potter about the computer..
> the old guy said...`i am not a fool you know, this
> is
> good science.`
>
>
>
>
>
>
>
>
>
> from: mel/minnetonka.mn.usa
> website: http://www.visi.com/~melpots/
>
> Clayart page link:
> http://www.visi.com/~melpots/clayart.html
>
>
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>
http://www.houstonpotters.com
Ivor and Olive Lewis on tue 11 jul 06
I always think of a kiln as a musical instrument. Came to that =
conclusion with the first one I ever constructed about forty years ago. =
The stack was made from 6 inch stoneware sewer pipes, four of them end =
on end. This kiln was wood fired, assisted with a bit of Gas Coke. When =
it started to get hot the velocity of the gas increased and a low deep =
throat started to howl, about four octaves below middle C. Just like a =
Cathedral Organ Pipe. Pure tone
All the kilns I have constructed have needed Tuning, just as you might =
alter the pitch of a Cello or a flute. Tuning a kiln is part of the art =
of firing. Do they equip folk with tuning forks when they graduate from =
Ceramics School ? Stories on Clayart seem to suggest not. So does Mel.
Best regards.
Ivor Lewis.
Redhill,
South Australia.
=20
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