Cheryl L Litman on sun 11 apr 99
Someone mentioned having this Duncan lowfire glaze turn out white instead
of red a while back. Did you ever figure out why that happened? I just
fired a few pieces in my big kiln along with a stoneware bisque and they
are snow white compared to the previous successes I've had in my test
kiln.
Cheryl Litman
Somerset, NJ
email: cheryllitman@juno.com
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Dee Clay on mon 12 apr 99
Hi Cheryl,
I've found that red is the most tempermental color to work with.
When I fire red I always fire to ^06 and turn the electric kiln directly to
high. Almost 100% success rate. Ofcourse you can't fire with anything green.
Good luck.
Diane in beautiful Miami.
Jim Brooks on mon 12 apr 99
Cheryl. the low fire red glaze that you had trouble with is a very good
glaze. It will however, turn white, gray, etc. if:
1.It is fired too high............and a cone over is too high.
2. The kiln is not vented properly. It must have a supply of fresh air.
any hint of reduction will scare the color out of it..!!! try firing your
kiln ..top vented to about 1100/1200 degrees F. Then when you do close the
top. leave the peep hole plugs out. ( this is most important.)
3. If it is fired with high copper glazes you will also lose the red
color.... If I have several pieces of red to fire..I try to use a smaller
kiln and fire only that color.
doug shea on mon 12 apr 99
Cheryl,
I've been told that the speed of the firing and the amount of
oxygen are important in low fire reds. The faster you can fire and the
more oxygen that you expose the glaze to, the better it will be. I
haven't used low fire reds in a regular electric kiln, but others in the
studio have and gotten terrible results. (We bisque-fire slowly, lots of
clunky heavy beginner pots) I have used low-fire reds, including duncan
glazes, when raku firing. Fast firing, lots of oxygen, beautiful
results.
Hope this helps
Jim Shea
tmartens on mon 12 apr 99
Cheryl
If you are talking about the brush on glaze rather than the
underglaze, I have found that it is verrrrrrrrry temperature
sensitive. Just a degree or two over and it came up glossy white.
Not what I had in mind for Christmas ornaments!
Toni in Durbs South Africa, where I felt COLD tonight, actual
shivery-put-on-a-sweater cold.Sigh of happiness from this end of the
globe
----------------------------Original message----------------------------
Someone mentioned having this Duncan lowfire glaze turn out white instead
of red a while back. Did you ever figure out why that happened? I just
fired a few pieces in my big kiln along with a stoneware bisque and they
are snow white compared to the previous successes I've had in my test
kiln.
Cheryl Litman
Somerset, NJ
email: cheryllitman@juno.com
___________________________________________________________________
You don't need to buy Internet access to use free Internet e-mail.
Get completely free e-mail from Juno at http://www.juno.com/getjuno.html
or call Juno at (800) 654-JUNO [654-5866]
D. McDysan on mon 12 apr 99
Cheryl,
My experience over the years with most low fire reds is that they need
to be fired quickly but most importantly with lots of oxygen in the kiln
especially at the temps where the color is developing. Early on when I
tried to put glazed pieces in with the bisque, the reds either burned
out completely or faded to an undesirable patchy red/white/clear. I
think the reason reds don't develop well in a bisque firing (even though
the temp is right) is because they are generally packed more tightly and
release gases from the clay into the atmosphere, thus reducing the
amount of oxygen (not the same as high fire reduction) present which
starves the glazes and burns them out.
Unfortunately when I tried to add more glaze and refire the results were
unacceptable. The best thing is to follow instructions on the label and
fire reds in a glaze firing with plenty of oxygen. You should have
consistent and beautiful low fire reds.
Debbie McDysan
dmcdysan@onramp.net
John Baymore on mon 12 apr 99
------------------
(snip)
Someone mentioned having this Duncan lowfire glaze turn out white instead
of red a while back. Did you ever figure out why that happened? I just
fired a few pieces in my big kiln along with a stoneware bisque and they
are snow white compared to the previous successes I've had in my test
kiln.
(clip)
Cheryl,
Cadmium based red (most blood-red lowire glazes and underglazes) is
notoriously sensitive to any sulphur in the atmosphere in the kiln. Fire
it in a bisque and you are pretty sure to lose it since most clays contain
some sulphur contamination. The higher this sulphur contamination in the
atmosphere the larger the likelyhood of the problem in mixed cadmium red
glaze/bisque firings. Best thing is to not fire them together.
Also, if you bisque too low or too fast on the body the glaze is applied to
and IT still contains much sulphur going into the glaze firing, you'll lose
the color too, either overall or in splotchy spots at lower levels of
sulphur.
Hope this helps with the mystery.
Best,
........................john
John Baymore
River Bend Pottery
22 Riverbend Way
Wilton, NH 03086 USA
603-654-2752
JBaymore=40Compuserve.com
Morgan Britt on tue 13 apr 99
Don't use low fire glaze any more but remember my old red experiences. The
bottom of my kiln fires about 1/2 a cone lower than the rest. I put low fire
reds on the bottom and fire to ^06 and they are beautiful, but up higher they
will turn white. Also use an envirovent.
John Baymore wrote:
> ----------------------------Original message----------------------------
> ------------------
> (snip)
>
> Someone mentioned having this Duncan lowfire glaze turn out white instead
> of red a while back. Did you ever figure out why that happened? I just
> fired a few pieces in my big kiln along with a stoneware bisque and they
> are snow white compared to the previous successes I've had in my test
> kiln.
>
> (clip)
>
> Cheryl,
>
> Cadmium based red (most blood-red lowire glazes and underglazes) is
> notoriously sensitive to any sulphur in the atmosphere in the kiln. Fire
> it in a bisque and you are pretty sure to lose it since most clays contain
> some sulphur contamination. The higher this sulphur contamination in the
> atmosphere the larger the likelyhood of the problem in mixed cadmium red
> glaze/bisque firings. Best thing is to not fire them together.
>
> Also, if you bisque too low or too fast on the body the glaze is applied to
> and IT still contains much sulphur going into the glaze firing, you'll lose
> the color too, either overall or in splotchy spots at lower levels of
> sulphur.
>
> Hope this helps with the mystery.
>
> Best,
>
> ........................john
>
> John Baymore
> River Bend Pottery
> 22 Riverbend Way
> Wilton, NH 03086 USA
>
> 603-654-2752
> JBaymore@Compuserve.com
--
Morgan Britt
morgan@unlimited.net
Caroline Cheng on tue 13 apr 99
One more thing about firing reds is that leave at least an inch in
between each piece in the kiln for more oxygen to flow around.
Caroline in Hong Kong
90 degrees and sunny
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