L. P. Skeen on tue 30 dec 03
yay me! I just got my new Paragon TnF today. it's almost at the end of =
the "break in firing", so I will be able to glaze fire tomorrow all the =
stuff that's been sitting around waiting. =20
In the manual for the Orton computer that came on the kiln, it tells =
that in addition to regular firing features, there is a cooling rate =
calculation already figured into the firing program. It's set to "0", =
meaning once it reaches ^6 it shuts off and cools naturally, but I can =
set it to ramp DOWN at a certain number degrees per hour. =20
Much has been said here about firing down for crystal growth, and the =
manual mentions color shift as well. What is the optimum cooling rate =
to set on the 'puter? I THINK my oval naturally cooled at about 200* =
per hour. At what point is the glaze cool enough that it's pointless to =
downfire further? I don't want my glaze firings to run 20 hours.....
Thanks
L
L. P. Skeen www.living-tree.net
Living Tree Pottery, Summerfield, NC
"There are three kinds of men. The ones who learn by reading, and the =
few who learn by observation. The rest of them have
to pee on the electric fence."------- Will Rogers (att.) =20
John Hesselberth on wed 31 dec 03
On Wednesday, December 31, 2003, at 03:08 PM, Dewitt wrote:
> Yes, Licorice does that for me and I rather like the effect.
>
> A question for you John, can a glaze's stability be altered by the cool
> down cycle? It seems like the development of crystals creates
> localized
> differences in the glaze components. For example, might Licorice that
> has
> been slow cooled and develops a "tea dust" effect be less stable than
> the
> more quickly cooled straight black version?
Hi deg,
I can only offer an opinion on your question as I only have one or two
data points. On licorice, which is an extremely stable glaze, I
couldn't see any measurable difference, but all the numbers were quite
low. I've tested that glaze a lot of times. The other tested glazes
were all fired at conditions very similar to the ones I described in
the earlier message. My opinion would be that there would not be a big
difference; maybe a small, but measurable, one under the right
conditions--but that is just what it is--an opinion.
To test it properly I'd have to use a glaze that was more loaded up
with something like copper which comes out more readily. So many things
to explore, so little time.
Regards,
John
http://www.frogpondpottery.com
http://www.masteringglazes.com
Elzbieta Sekula on wed 31 dec 03
I am SOOOO jealous! Congratulations! Elzbieta
In a message dated 12/31/03 6:00:53 AM Central Standard Time,
lpskeen@LIVING-TREE.NET writes:
> yay me! I just got my new Paragon TnF today. it's almost at the end of
> the "break in firing", so I will be able to glaze fire tomorrow all the stuff
> that's been sitting around waiting.
>
> In the manual for the Orton computer that came on the kiln, it tells that in
> addition to regular firing features, there is a cooling rate calculation
> already figured into the firing program. It's set to "0", meaning once it
> reaches ^6 it shuts off and cools naturally, but I can set it to ramp DOWN at a
> certain number degrees per hour.
John Rodgers on wed 31 dec 03
Congratulations, Lisa!!!
Your new kiln sounds like a dream. I just got a new Paragon SnF
(Set-n-Fire) the manually fired automatic. I just hapened to stumble on
a brand spanking new one that someone had stored for two years. It had
never even been taken out of the shipping crate. Got it for dirt, so
couldn't pass it by. So I spent my TnF savings on the SnF. Oh well,
maybe later I will get the computer controlled model.
I envy you!!! You will have so much fun with your new kiln, especially
being able to do those crystal glaze firings with good control. It's
something I want to do, but the precision is not there in the manual
kilns. Well, there's plenty to do though.
Well, have fun. And post some pictures of your lastest that has been
fired in the new kiln.
Best,
John Rodgers
Chelsea, AL
L. P. Skeen wrote:
>yay me! I just got my new Paragon TnF today. it's almost at the end of the "break in firing", so I will be able to glaze fire tomorrow all the stuff that's been sitting around waiting.
>
>In the manual for the Orton computer that came on the kiln, it tells that in addition to regular firing features, there is a cooling rate calculation already figured into the firing program. It's set to "0", meaning once it reaches ^6 it shuts off and cools naturally, but I can set it to ramp DOWN at a certain number degrees per hour.
>
>Much has been said here about firing down for crystal growth, and the manual mentions color shift as well. What is the optimum cooling rate to set on the 'puter? I THINK my oval naturally cooled at about 200* per hour. At what point is the glaze cool enough that it's pointless to downfire further? I don't want my glaze firings to run 20 hours.....
>
>Thanks
>L
>
>
>
>L. P. Skeen www.living-tree.net
>Living Tree Pottery, Summerfield, NC
>"There are three kinds of men. The ones who learn by reading, and the few who learn by observation. The rest of them have
>to pee on the electric fence."------- Will Rogers (att.)
>
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>
Elzbieta Sekula on wed 31 dec 03
I'm ever jealous-er! Seriously, I am thrilled for your finding a "bird's nest
on the ground". Now, please send some of that good karma my way! E
In a message dated 12/31/03 8:11:02 AM Central Standard Time,
jh_rodgers@BELLSOUTH.NET writes:
> Your new kiln sounds like a dream. I just got a new Paragon SnF
> (Set-n-Fire) the manually fired automatic. I just hapened to stumble on
> a brand spanking new one that someone had stored for two years. It had
> never even been taken out of the shipping crate. Got it for dirt, so
> couldn't pass it by. So I spent my TnF savings on the SnF. Oh well,
> maybe later I will get the computer controlled model.
>
John Hesselberth on wed 31 dec 03
On Tuesday, December 30, 2003, at 11:51 PM, L. P. Skeen wrote:
> What is the optimum cooling rate to set on the 'puter? I THINK my
> oval naturally cooled at about 200* per hour. At what point is the
> glaze cool enough that it's pointless to downfire further? I don't
> want my glaze firings to run 20 hours.....
Hi Lisa,
It depends... You knew that was coming didn't you. I have settled on
dropping quickly (500F/hr) down to 1900 (after a 15 minute soak at
peak), then going down 125F/hr to 1400 where I shut it off. But it
really depends on the specific formulation of your glaze and what
effects you are wanting.
I guess I would say, though, that glazes properly formulated to be
durable and glossy or durable and matte can all be fired down in the
way I mention above and do well. Some that are glossy when cooled
rapidly might develop a few crystals when cooled more slowly and become
semiglossy or show some 'tea dust'--I think Licorice does this in some
potter's hands.
And yes, firing cycles can stretch to 12-15 hours when you fire this
way. Such is life.
Regards,
John
http://www.frogpondpottery.com
http://www.masteringglazes.com
Dewitt on wed 31 dec 03
At 10:56 AM 12/31/2003, you wrote:
>Some that are glossy when cooled
>rapidly might develop a few crystals when cooled more slowly and become
>semiglossy or show some 'tea dust'--I think Licorice does this in some
>potter's hands.
Yes, Licorice does that for me and I rather like the effect.
A question for you John, can a glaze's stability be altered by the cool
down cycle? It seems like the development of crystals creates localized
differences in the glaze components. For example, might Licorice that has
been slow cooled and develops a "tea dust" effect be less stable than the
more quickly cooled straight black version?
deg
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