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element life and slow cooling

updated fri 12 nov 10

 

Heather Bessey on tue 9 nov 10


A skutt technician told me that the slow cool program provided in John and =
=3D
Ron's book would reduce my element life by 50%.
Why would this be? I realize the elements would be preforming longer. I p=
=3D
rogramed to drop naturally to 1800 degrees and then
125 degrees down to 1500 degrees. Reading the meter this slow cooled seeme=
=3D
d to use only 3 kilowattes. Is there another reason slow cool would be har=
=3D
d on element life?
Thanks
Heather =3D

John Hesselberth on wed 10 nov 10


On Nov 9, 2010, at 12:26 PM, Heather Bessey wrote:

> A skutt technician told me that the slow cool program provided in John =
=3D
and Ron's book would reduce my element life by 50%.
> Why would this be? I realize the elements would be preforming longer. =
=3D
I programed to drop naturally to 1800 degrees and then
> 125 degrees down to 1500 degrees. Reading the meter this slow cooled =3D
seemed to use only 3 kilowattes. Is there another reason slow cool =3D
would be hard on element life?
> Thanks
> Heather =3D20

Hi Heather,

I hope this was not a recent conversation. Skutt's technician was =3D
criticizing slow cooling several years ago. Ron and I had a conversation =
=3D
with Jim Skutt about this at NCECA a few years back. While slow cooling =3D
might have a small effect on element life if it is done all the way from =
=3D
peak stoneware temperature, I'm not aware that there is any data that =3D
says it would approach 50%. And if you drop naturally to 1800 or 1900 =3D
and then start to slow cool (which is what we recommend in MC6Gs from =3D
the third printing on) it will have virtually no measurable effect on =3D
element life. After all those temperatures are in the bisque or =3D
earthenware range and elements last for years and years if only fired to =
=3D
those temperatures.

But even if it did effect element life in a measurable way the key =3D
question is whether or not you think the effects you get are worth the =3D
cost. And if it was a recent conversation, please let Ron or me know. We =
=3D
may need to ask to see Skutt's data.

Regards,

John=3D

Arnold Howard on wed 10 nov 10


From: "Heather Bessey"
A skutt technician told me that the slow cool program
provided in John and Ron's book would reduce my element life
by 50%.
Why would this be?
-------------
Controlled cooling reduces element life--but the percentage
varies depending on the kiln wall thickness and length of
the controlled cooling. 50% sounds high for a ceramic kiln.

Much of the wear on elements occurs where the elements
struggle to reach high temperatures. The more they struggle,
the faster they wear out. Controlled cooling is much easier
on elements.

To get the most out of your elements, begin the controlled
cooling at the optimum temperature and no sooner, and
maintain the controlled cooling for as short a period as
necessary.

A thick-walled kiln can often achieve the effects of slow
cooling without actually turning on the elements again after
the cone bends.

Sincerely,

Arnold Howard
Paragon Industries, L.P., Mesquite, Texas USA
ahoward@paragonweb.com / www.paragonweb.com

William & Susan Schran User on wed 10 nov 10


On 11/9/10 12:26 PM, "Heather Bessey" wrote:

> A skutt technician told me that the slow cool program provided in John an=
d
> Ron's book would reduce my element life by 50%.
> Why would this be?

Just having the elements turned on will reduce their life span.
Think of the elements as another one of your tools and all of your tools
will wear out over time.
Using your tools (elements) in a way that produces your desired results is
just part of the process.
Whether following the Mastering ^6 firing schedule will reduce element life
by 50%, I don't know, but I am suspicious.

Now, if you were firing crystalline glazes to cone 10, getting closer to to=
p
rated temperature of the elements, then doing 4-6 hour temperature holds at
2000F - 1950F, then yes, you would quickly reduce element life.

I would stick with the desired firing schedule and get good glaze results.

Bill

--
William "Bill" Schran
wschran@cox.net
wschran@nvcc.edu
http://www.creativecreekartisans.com

David Martin Hershey on thu 11 nov 10


Hi Heather,

FWIW, I've had very good element life
on my heavily used vented Skutt KM 1027.

I've fired down on almost all firings,
bisque ^04, and glaze ^5-6.
I don't stuff the kiln full every time.
That may be helping.

However, I've not been so lucky
with the relays. Don't know if it's related
to the firing schedule, or what.

After the last failure,
Skutt sent me a re-designed relay package.
We'll see how they hold up.

Best, DMH

David Martin Hershey
DMH Studio + Design
2629 Manhattan Ave #137
Hermosa Beach CA USA
90254-2447 424.241.3809
http://www.dmhstudio.com/
http://www.obamacardgold.com
http://www.winetastingtrolley.com/


> On 11/9/10 12:26 PM, "Heather Bessey" wrote:
>
>
>> A skutt technician told me that the slow cool program provided in John a=
nd
>> Ron's book would reduce my element life by 50%.
>> Why would this be?
>>