Dina Barnese on tue 27 sep 11
I am just learning to fire my electric kiln, in fact, I have done one test
firing so far with shelves only, and I did that too quickly. I went
according to the firing schedule that came with the kiln but I learned that
I need to slow it down.
For bisque loads in my gas kiln, I've always loaded it up the night before
and candled it with the pilot light overnight to drive out any possible
remaining moisture. There doesn't seem to be a setting on the electric kiln
(Skutt KS1018) for an extremely low setting, so I'm wondering if any of you
use this technique in electric or if you just make sure everything is bone
dry before firing? I was thinking about turning the kiln onto low up to
about 180 degrees then turning it off... but I don't want to hurt the
elements and am not sure if this would hurt them or not.
Do any of you use the kiln for final drying of greenware?
Thanks,
Dina Barnese
Zizziba Studio
Flagstaff, Arizona
Steve Mills on tue 27 sep 11
What I have done in the past is to set the program to reach one hundred and=
t=3D
en degrees C in five hours and then soak at that for (in my case) 5 more. T=
h=3D
e last figure doesn't always happen if I'm then going to fire to bisque str=
a=3D
it away.=3D20
Try it
Steve M
Steve Mills
Bath
UK
www.mudslinger.me.uk
Sent from my Ipod touch
On 27 Sep 2011, at 17:41, Dina Barnese wrote:
> I am just learning to fire my electric kiln, in fact, I have done one tes=
t=3D
> firing so far with shelves only, and I did that too quickly. I went
> according to the firing schedule that came with the kiln but I learned th=
a=3D
t
> I need to slow it down.
>=3D20
> For bisque loads in my gas kiln, I've always loaded it up the night befor=
e=3D
> and candled it with the pilot light overnight to drive out any possible
> remaining moisture. There doesn't seem to be a setting on the electric ki=
l=3D
n
> (Skutt KS1018) for an extremely low setting, so I'm wondering if any of y=
o=3D
u
> use this technique in electric or if you just make sure everything is bon=
e=3D
> dry before firing? I was thinking about turning the kiln onto low up to
> about 180 degrees then turning it off... but I don't want to hurt the
> elements and am not sure if this would hurt them or not.
>=3D20
> Do any of you use the kiln for final drying of greenware?
>=3D20
> Thanks,
>=3D20
> Dina Barnese
> Zizziba Studio
> Flagstaff, Arizona
David Hendley on tue 27 sep 11
I bet just about everyone does a slow pre-heat to a few hundred
degrees for bisque firings.
I have an old manual kiln, with 3 switches, each with low, medium,
and high settings. I prop open the lid slightly, and remove the 3
peephole plugs, and turn on only the bottom element on low for
4 hours, then all 3 elements on low for another 2 hours.
This may be more time than is required, but little electricity is used
on the low settings, so I think it is better not to rush things, and I
never have anything break from firing too fast.
Even if some of the pots are slightly damp, this time schedule
works fine.
If it is more convenient for you, because of the logistics of going
to your studio, it would not be unreasonable to leave the bottom
element on low overnight - not much more energy use than leaving
a couple of lights on overnight.
There is no reason you should not turn the elements on and off as
you please. On the way back down, during cooling, I turn on
the elements again, at about 1600 degrees, for half an hour, to
slow down the cooling - it helps large bowls and platters survive
without cracks from uneven cooling.
David Hendley
david@farmpots.com
http://www.farmpots.com
http://www.thewahooligans.com
----- Original Message -----
>I am just learning to fire my electric kiln, in fact, I have done one test
> firing so far with shelves only, and I did that too quickly. I went
> according to the firing schedule that came with the kiln but I learned
> that
> I need to slow it down.
>
> For bisque loads in my gas kiln, I've always loaded it up the night befor=
e
> and candled it with the pilot light overnight to drive out any possible
> remaining moisture. There doesn't seem to be a setting on the electric
> kiln
> (Skutt KS1018) for an extremely low setting, so I'm wondering if any of
> you
> use this technique in electric or if you just make sure everything is bon=
e
> dry before firing? I was thinking about turning the kiln onto low up to
> about 180 degrees then turning it off... but I don't want to hurt the
> elements and am not sure if this would hurt them or not.
>
> Do any of you use the kiln for final drying of greenware?
Vince Pitelka on tue 27 sep 11
Dina Barnese wrote:
"For bisque loads in my gas kiln, I've always loaded it up the night before
and candled it with the pilot light overnight to drive out any possible
remaining moisture. There doesn't seem to be a setting on the electric kiln
(Skutt KS1018) for an extremely low setting, so I'm wondering if any of you
use this technique in electric or if you just make sure everything is bone
dry before firing? I was thinking about turning the kiln onto low up to
about 180 degrees then turning it off... but I don't want to hurt the
elements and am not sure if this would hurt them or not.
Hi Dina -
At the Appalachian Center for Craft we always do a preheat before starting
the regular bisque schedule. If your kiln is a programmable, there will be
a feature to set a preheat for as many hours as you want, and it will hold
the kiln around 180 degrees. We always leave a softbrick spacer under the
lid holding it up about an inch and a half during the preheat. We generall=
y
preheat for from 4 to 10 hours depending on the thickness and dampness of
the wares. As long as we do this, we have far less loss from pieces
cracking or popping in the bisque. It costs very little to do the preheat
compared to the cost of the rest of the firing, and if it saves a few
pieces, it is well worth it.
- Vince
Vince Pitelka
Appalachian Center for Craft
Tennessee Tech University
vpitelka@dtccom.net
http://iweb.tntech.edu/wpitelka/
Snail Scott on wed 28 sep 11
On Sep 27, 2011, at 11:41 AM, Dina Barnese wrote:
> For bisque loads in my gas kiln, I've always loaded it up the night befor=
e
> and candled it with the pilot light overnight to drive out any possible
> remaining moisture. There doesn't seem to be a setting on the electric ki=
ln
> (Skutt KS1018) for an extremely low setting, so I'm wondering if any of y=
ou
> use this technique in electric or if you just make sure everything is bon=
e
> dry before firing? I was thinking about turning the kiln onto low up to
> about 180 degrees then turning it off... but I don't want to hurt the
> elements and am not sure if this would hurt them or not.
No, it won't hurt the elements, but if you turn on
the elements all together, even on 'low', it gets
pretty hot pretty queckly, especially near the elements.
You may achieve a 180F _average_ temperature, but
I guarantee it will be hotter near the walls. Unless your
work is quite thin, or a very 'open' body, don't do it!
Instead, candle on one ring only, on 'low', with the lid
propped slightly open. We just had a discussion of this
a few weeks ago, and I expressed my preference for
candling with the top ring. Without reiterating the whole
discussion, I find this gives me the most even candling.
I know any people prefer to candle with the bottom ring,
but I find that this makes for a very steep temperature
gradient: too hot too quickly on the bottom, especially
if tightly packed, and too cool on the top until long after
the bottom is ready. Using the top element does lose
some heat out the top through convection, but the radiant
heat makes for a nice even candling throughout, with
no hot spots and cold zones. A few hours is sufficient
for even quite thick work.
Candling all night is overkill on most cases. Even with my
very thick work, a few hours usually suffices. Candling
overnight does let you get an early start on the actual
firing, however, and allow you to reach temperature at a
time that is more compatible with the rest of your life.
Using a long candle to dry out work is a personal choice.
It's certainly more expensive and less 'green' than air-drying,
but when deadlines press and the air is damp, it can be
handy, and gets the stuff out of your way when the work is
piling up waiting to dry.
-Snail
>
> Do any of you use the kiln for final drying of greenware?
>
> Thanks,
>
> Dina Barnese
> Zizziba Studio
> Flagstaff, Arizona
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