pattravis on tue 19 apr 05
Hello, Clayarters. I'm relatively new to Clayart, but have read enough
that I know some of you will be able to help me. I am a pottery student
at an art center and have been learning to fire an updraft gas kiln to
cone 10 in reduction.
Here's my situation. I want to get beautiful copper reds in an updraft
gas kiln that also holds pots glazed with celadons, shinos, and opaque
soft finish glazes. I have read that copper red flashes on the cool
down between 1472 F and 1100 F, and that another reduction during the
cooldown in that temperature range will help.
The kiln has a dual pyrometer, but no oxygen probe. It has two burners.
My questions are:
1. When I kick the burners back on, do I kick both burners on?
2. How high should the burners go?
3. How long should the burners be on?
4. What should the temperature in the kiln be doing?
5. I'm assuming the dampers should remain closed, right?
6. What effect will this additional reduction phase have on the
other glazes?
Any input would be greatly appreciated.
Pat Travis
pottery@pattravisokc.com
Kris Bliss on wed 20 apr 05
hi
on your questions which i just briefed....
you may be looking at it wrong , or, here is a different take
in my updrft to get reds, i stack them in the center of the kiln and
make sure they are well blocked, if not by other pots (stuff with copper
are good) then i stack kiln posts around the pots i want red.....
min. clearance with the shelf above.
holds the heat, etc. ... so i am blocking all around, sorta
building a saggar effect...
and then fire for the other pots...
...note.. updrafts will cool faster... if you want to slow that down,
block the bottom with old kiln sheves brick whatever... ive heard
steel works.....
works for me
good luck
bliss
I am a pottery student
> at an art center and have been learning to fire an updraft gas kiln to
> cone 10 in reduction.
> Here's my situation. I want to get beautiful copper reds in an updraft
> gas kiln that also holds pots glazed with celadons, shinos, and opaque
> soft finish glazes. I have read that copper red flashes on the cool
> down between 1472 F and 1100 F, and that another reduction during the
> cooldown in that temperature range will help.
>
>
>
> The kiln has a dual pyrometer, but no oxygen probe. It has two burners.
> My questions are:
>
> 1. When I kick the burners back on, do I kick both burners on?
> 2. How high should the burners go?
> 3. How long should the burners be on?
> 4. What should the temperature in the kiln be doing?
> 5. I'm assuming the dampers should remain closed, right?
> 6. What effect will this additional reduction phase have on the
> other glazes?
>
>
>
> Any input would be greatly appreciated.
>
>
>
> Pat Travis
>
> pottery@pattravisokc.com
>
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pattravis on thu 21 apr 05
Thank you, Kris, for your immediate response. I will try your
suggestion this weekend. As far as the cool down time, it takes from
about 8:30 p.m. Monday until 8:00 p.m. Wednesday for the kiln temp to
get below 300 F. Is that took fast a cool down? We do have kiln
shelves, bag walls, and bricks in the bottom of the kiln. Should we
maybe set bricks and posts in the very small empty spaces among the pots
throughout the kiln to get a slower cool down?
Pat Travis
pattravis@cox.net
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