mel jacobson on wed 12 jul 06
the goal of firing a kiln is to get
everything in that kiln to fire to the
cone temperature that you desire.
(the emphasis is on what `you` desire.)
100% perfect pots...no failure.
how you get there, is up to the potter firing
the kiln.
if a bag wall serves your purpose, and does not
impair the firing cycle....put in a bag wall.
if your pots need protection from flame, put in
a bag wall/sagger system.
but, if your kiln is two cones hotter on the bottom,
than on the top... perhaps there is something wrong.
find out what is wrong, don't keep firing the kiln that way.
if atmospheric heating is teaching us anything, it is
teaching us to fire kilns the best way we know how.
the best way.
if you are firing for twenty hours in a gas kiln, find
out how to fire in twelve. if you fire in twelve, find
out how to reach temp in six.
experiment in reduction...how much do you really need? and
find a perfect way to reduce without slowing your kiln.
perhaps firing down will solve your problem.
when i fire down at 1900F the pots seem to all change
and become one. there are no hot spots any longer, and
the reduction is the same on every pot.
when i speed fire at the farm to cone 13 oxidize the pots
seem to take on a much better quality. then i fire down
for two hours...bingo...got it. i have never had more consistent
pots. some running of course, but i plan that in. it is part of the deal.
saving fuel is critical in 2006. it is expensive. really expensive.
see tom wirt's post on the fuel it takes to make one mug...over a dollar.
so, why would anyone on purpose, fire a kiln for 30 hours to make 5 dollar
mugs.
putting in a spiral pipe stack with flue liners to cut off three hours of
firing time would be worth the money, fifty times over.
the math is not hard to do: 25% saving over 25 firings= money
in my pocket and i help keep heat out of the sky.
mel
individual, working potters get it...right away. they pay their own bills.
the problem is colleges and art centers..old equipment, no
one monitoring the problems, changing staff and tech help.
it just goes on for years. and the cost is filtered out to others.
and, in many cases, the technology of the staff is out of a book
written in 1947.
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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