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body reduction/try it

updated mon 19 oct 09

 

mel jacobson on sun 18 oct 09


a group of us has been doing body reduction
on the way down....during cooling.

you could fool me, but it works either way.
up or down.

we have fired dozens of kilns with bob anderson and
others....we fire oxy all the way to maturity.
add wood to a tight/buttoned up kiln during the cooling.
just small sticks about every half hour. it smokes like mad,
so vent well. our kilns are outside...so no problem.

in my big kiln i just add scrap wood. ends of 1x2's sort of stuff,
from my wood working pile.
the burner ports have brick covers, and we just toss it in.

by firing in neutral, we save gobs of gas. things fire faster
and easier.

we get great body and glaze reduction.

of course i have said many times...gobs of smoke, and dirty
flame is just a waste. fire clean.
blue flame. and, if you wish, use your damper to get light reduction.
it costs nothing to throw in sticks.

it seems to me, the clay body does not seal.
everything is liquid in that kiln, why would carbon not
trap in the clay at 2350f?

i have done great shino glazes with no early reduction.
just at the end.

i think this is like what nils calls `play`. we never have fear
that we will make a mistake, or lose a pot.
we play with kilns...or in my words...we `work kilns` in a different
way...see what happens. it is usually a big surprise.

try firing with one burner as high as it will go, then turn the other
one almost off...see the heat move across the kiln.
fire at high pressure, and heat the bottom, low gas and the
top gets hot. see how your kiln reacts.
add three feet to your stack, take off three feet.
try firing at the lowest pressure you can get with your burners
and see if the kiln increases in temp.
why not?

the best definition of stupid is:
`the kiln stalls, but i just keep doing what i do....84
firings now...and it always stalls`. now that is dumb.
i would have that kiln changed the minute it stalled.
and, i would never fire again til we figured it out.

that is the great thing about having group firings...kurt says this,
bob and andy say that, try this, try that...who gives a crap about
the pots...we can make more tomorrow...learn first. then kerry brooks
has a great idea, we try it. no fear. kerry can fire a kiln and she
likes 12 melted.

of course we have to draw i pix of the cones with chalk, on the kiln.
we shut it off at this angle!....of course i think cone 10 is 11 melted.
so the drawing is critical. keeps fights from breaking out.
that small kiln will get done fast, you know, cone 9, and bob anderson
runs to get a beer, and 11 is over.
mel


from: minnetonka, mn
website: http://www.visi.com/~melpots/
clayart link: http://www.visi.com/~melpots/clayart.html
new book: http://www.21stcenturykilns.com