Brother Augustine on thu 21 jun 01
Hi,
We're firing a 12 cu.ft. Geil propane gas brick kiln to cone 9 reduction =
for copper reds and other glazes. We seem to get uneven reduction =
which causes flashing and a white-out of the copper reds on the sides of =
pots that are facing the walls of the kiln. We've got the primary air =
down to about an 1/8" on the burners to cut down on oxygen. Does anyone =
else have this problem? Is there a way with these kilns to get more =
even reduction?
Is there someone in the area firing a Geil propane gas kiln?
Thanks for any help you can offer,
br Augustine,
braugustine@westonpriory.org
Weston, Vermont
Hank Murrow on thu 21 jun 01
>Hi,
>We're firing a 12 cu.ft. Geil propane gas brick kiln to cone 9 reduction
>for copper reds and other glazes. We seem to get uneven reduction which
>causes flashing and a white-out of the copper reds on the sides of pots
>that are facing the walls of the kiln. We've got the primary air down to
>about an 1/8" on the burners to cut down on oxygen. Does anyone else have
>this problem? Is there a way with these kilns to get more even reduction?
>
>Is there someone in the area firing a Geil propane gas kiln?
>
>Thanks for any help you can offer,
>
>br Augustine,
Dear Fra Augustine;
I suggest that you use the damper to cut down the air instead of
the primary. This will create more turbulence in the kiln which is likely
to make the atmosphere appear more even in the copper reds.
Good Luck, and cheers! Hank in Eugene
Craig Martell on thu 21 jun 01
Hi:
Your problem with fugitive reds could be duration at hi temp too. The
sides of the pots near the walls could be getting hotter quicker due to
their proximity to the burners. If you hold copper reds at higher temps
there is a greater chance of losing the color due to the volatilizing of
the copper. Try firing some small pieces in this same location in saggers
or perhaps with a firebrick between the pot and the flame.
regards, Craig Martell in Oregon
Earl Brunner on thu 21 jun 01
I have a small Geil fiber kiln that I fire with natural gas. I can get
copper reds in it, but I have to be very careful where I place the reds
in the kiln, and I still get flashing or under reduced spots where the
copper doesn't turn red. I have heard that this can be a problem with
smaller kilns. Of course another problem I maybe having is that I hit
cone 11.5-12 frequently and I've heard that copper doesn't like that......
Brother Augustine wrote:
> Hi,
> We're firing a 12 cu.ft. Geil propane gas brick kiln to cone 9 reduction for copper reds and other glazes. We seem to get uneven reduction which causes flashing and a white-out of the copper reds on the sides of pots that are facing the walls of the kiln. We've got the primary air down to about an 1/8" on the burners to cut down on oxygen. Does anyone else have this problem? Is there a way with these kilns to get more even reduction?
>
> Is there someone in the area firing a Geil propane gas kiln?
>
> Thanks for any help you can offer,
>
> br Augustine,
>
> braugustine@westonpriory.org
> Weston, Vermont
>
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--
Earl Brunner
http://coyote.accessnv.com/bruec/
bruec@anv.net
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