Dana Henson on tue 20 jan 98
What is happening in the kiln atmosphere when you are getting green/orange
flames out of the damper, spyholes, etc.? I have seen the flames from the
damper a pea soup green. Can anyone tell me what this means? Results from
these firings were different than usual. The body reduction was not a toasty
golden color, but a muddy brown. The kiln was fired in mild reduction to C/10
after body reduction yet the flames were still that pea soup green, with
touches of pink and orange. The glazes were very clear and beautiful, however.
By the way, this is an Alpine updraft kiln. I have fired this kiln a number of
times before and had an orange flame with some green during body reduction and
better body reduction (golden color). Does anyone know why these changes in
atmosphere occur when the kiln is basically being fired in the same manner,
using the same glazes, etc.? Thanks for any input...
Dana Henson
G_Henson@venus.twu.edu
David Hendley on thu 22 jan 98
I think the green flames could be copper
volitizing from your glazes.
Did you have a lot of copper glazes in the kiln?
David Hendley
Maydelle, Texas
At 01:46 PM 1/20/98 EST, you wrote:
>----------------------------Original message----------------------------
>What is happening in the kiln atmosphere when you are getting green/orange
>flames out of the damper, spyholes, etc.? I have seen the flames from the
>damper a pea soup green. Can anyone tell me what this means? Results from
>these firings were different than usual. The body reduction was not a toasty
>golden color, but a muddy brown. The kiln was fired in mild reduction to
C/10
>after body reduction yet the flames were still that pea soup green, with
>touches of pink and orange. The glazes were very clear and beautiful,
however.
>By the way, this is an Alpine updraft kiln. I have fired this kiln a
number of
>times before and had an orange flame with some green during body reduction
and
>better body reduction (golden color). Does anyone know why these changes in
>atmosphere occur when the kiln is basically being fired in the same manner,
>using the same glazes, etc.? Thanks for any input...
>Dana Henson
>G_Henson@venus.twu.edu
>
>
Wesley R. Handrow on fri 23 jan 98
If have just about the right amount of reduction you will get a very
nice emerald green flame if you are using gas. You will get this color
even if you have no copper bearing glazes in the kiln. If there is a
lot of orange then you are wasting gas since to get the effects of
reduction on your body and glazes all you need to do is rob those
materials that are bonded with oxygen by having carbon monoxide at high
temp. in the kiln's atmosphere. In fact if you have a lot of orange
flame using gas you run the risk of bloating from carbon being trapped
in the body and then turning to a gas at high temp. later in the firing
inside the body.
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