Maid O'Mud on wed 26 mar 08
I bought my present Coneart kiln new in Sept. 03. I have over 100 firings
on it, mostly to ^6 fired with Ron & John's schedule.
I had the elements and entire kiln coated with ITC by Tucker prior to
delivery.
Initially the glaze loads fired 14 - 16 hours, depending on
weather/electricity demands etc. A few years go by, and each
year I can see the firing times getting a bit longer BUT the pots and
glazes are fine (no blistering or running). Interestingly,
the bisque fires (using the preprogrammed slow bisque) have only added .5
hours over 5 years.
Last glaze fire the kiln went over 23 hours, and was still firing down when
I turned it off @ 1540. Ran a bisque
fire next day, and the kiln ran fine.
I have yet to see an error code except when the power went off. We checked
all elements on the weekend, and
they all passed the paper test. Thermocouples (3) all show temps no
problem.
So, my question is - do I do anything? All parts are original in the kiln.
I need to run a glaze load shortly, and was
looking for some feedback before I load. Any suggestions?
Sam Cuttell
Maid O'Mud Pottery
RR 1
Melbourne, Ontario
N0L 1T0
CANADA
"First, the clay told me what to do.
Then, I told the clay what to do.
Now, we co-operate."
sam 1994
http://www.ody.ca/~scuttell/
scuttell@ody.ca
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Dannon Rhudy on wed 26 mar 08
If the elements are original to the kiln -
you need new ones. Should solve the
problem.
Someone will undoubtedly explain in
detail. But your elements are well
worn.
regards
Dannon Rhudy
> I bought my present Coneart kiln new in Sept. 03. I have over 100 firings
> on it, mostly to ^6 fired with Ron & John's schedule.
jonathan edward byler on wed 26 mar 08
my understanding of these things is that as the elements wear out it
becomes harder and harder for them to reach high temperatures. they
might check out fine cold, but I am thinking that the resistance at
high temperature goes up over time as they wear out. To my way of
thinking, the paper test does not really show how they will perform
at high temperature, more that they are capable of getting hot enough
to burn paper, which often times means they will get hot enough to
bring the kiln to temp but not always.
We have an olympic kiln here in the studio that reaches bisque temps
just fine, but will never reach cone 6 anymore. elements seem to
test fine using an ohmmeter, and the paper test, but I suspect that
If I were to measure amperage once it heats up, using a clamp on
ammeter, that the current draw would be lower than it is supposed to be.
My guess is you need to replace the elements, but someone else might
be able to tell you with more authority. I am only speaking from my
personal experience, which, although not extremely limited, is by no
means expert... YMMV.
best of luck with getting your problem fixed,
jon
jon byler
3-D Building Coordinator
Art Department
Auburn University, AL 36849
On Mar 26, 2008, at 6:38 PM, Maid O'Mud wrote:
> I bought my present Coneart kiln new in Sept. 03. I have over 100
> firings
> on it, mostly to ^6 fired with Ron & John's schedule.
> I had the elements and entire kiln coated with ITC by Tucker prior to
> delivery.
>
> Initially the glaze loads fired 14 - 16 hours, depending on
> weather/electricity demands etc. A few years go by, and each
> year I can see the firing times getting a bit longer BUT the pots and
> glazes are fine (no blistering or running). Interestingly,
> the bisque fires (using the preprogrammed slow bisque) have only
> added .5
> hours over 5 years.
>
> Last glaze fire the kiln went over 23 hours, and was still firing
> down when
> I turned it off @ 1540. Ran a bisque
> fire next day, and the kiln ran fine.
>
> I have yet to see an error code except when the power went off. We
> checked
> all elements on the weekend, and
> they all passed the paper test. Thermocouples (3) all show temps no
> problem.
>
> So, my question is - do I do anything? All parts are original in
> the kiln.
> I need to run a glaze load shortly, and was
> looking for some feedback before I load. Any suggestions?
>
> Sam Cuttell
> Maid O'Mud Pottery
> RR 1
> Melbourne, Ontario
> N0L 1T0
> CANADA
>
> "First, the clay told me what to do.
> Then, I told the clay what to do.
> Now, we co-operate."
> sam 1994
>
> http://www.ody.ca/~scuttell/
> scuttell@ody.ca
>
> No virus found in this outgoing message.
> Checked by AVG.
> Version: 7.5.519 / Virus Database: 269.22.0/1344 - Release Date:
> 26/03/2008
> 8:52 AM
>
> ______________________________________________________________________
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Steve Mills on thu 27 mar 08
Sam,
Many others have had similar problems to this. Mostly they can be explained by the gradual conversion of the element wire surface (under the ITC) from wire core to oxide layer, which of course doesn't work as a heating element, so as the oxide layer grows, the element core gets smaller and the firings take longer.
There is however sometimes another problem in there as well;
when was the last time you vacuumed the elements?
Very fine dust builds up over time on the elements, and despite coatings can reduce element efficiency. A good vacuuming can sometimes make a surprising difference to firing times.
Steve
Bath
UK
Maid O'Mud wrote:
I bought my present Coneart kiln new in Sept. 03. I have over 100 firings
on it, mostly to ^6 fired with Ron & John's schedule.
I had the elements and entire kiln coated with ITC by Tucker prior to
delivery.
Initially the glaze loads fired 14 - 16 hours, depending on
weather/electricity demands etc. A few years go by, and each
year I can see the firing times getting a bit longer BUT the pots and
glazes are fine (no blistering or running). Interestingly,
the bisque fires (using the preprogrammed slow bisque) have only added .5
hours over 5 years.
Last glaze fire the kiln went over 23 hours, and was still firing down when
I turned it off @ 1540. Ran a bisque
fire next day, and the kiln ran fine.
I have yet to see an error code except when the power went off. We checked
all elements on the weekend, and
they all passed the paper test. Thermocouples (3) all show temps no
problem.
So, my question is - do I do anything? All parts are original in the kiln.
I need to run a glaze load shortly, and was
looking for some feedback before I load. Any suggestions?
Sam Cuttell
Maid O'Mud Pottery
RR 1
Melbourne, Ontario
N0L 1T0
CANADA
"First, the clay told me what to do.
Then, I told the clay what to do.
Now, we co-operate."
sam 1994
http://www.ody.ca/~scuttell/
scuttell@ody.ca
No virus found in this outgoing message.
Checked by AVG.
Version: 7.5.519 / Virus Database: 269.22.0/1344 - Release Date: 26/03/2008
8:52 AM
______________________________________________________________________________
Clayart members may send postings to: clayart@lsv.ceramics.org
You may look at the archives for the list, post messages, change your
subscription settings or unsubscribe/leave the list here: http://www.acers.org/cic/clayart/
Moderator of the list is Mel Jacobson who may be reached at melpots2@visi.com
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John Britt on thu 27 mar 08
One easy way to check the elements is to turn the kiln on high and wait
about 10 minutes. Then, with a golve on, open the lid a crack and see if
the elements are glowing and how strong.
If they are new and strong they will be bright and hot. But as the kiln
progressively gets older they will be dull and not very hot. If you do
this periodically you will see the effect of age on the elements.
You can also see when an element is broken and doesn't heat.
Hope it helps,
John Britt
Arnold Howard on thu 27 mar 08
From: "jonathan edward byler"
> We have an olympic kiln here in the studio that reaches
> bisque temps
> just fine, but will never reach cone 6 anymore. elements
> seem to
> test fine using an ohmmeter, and the paper test, but I
> suspect that
> If I were to measure amperage once it heats up, using a
> clamp on
> ammeter, that the current draw would be lower than it is
> supposed to be.
-------------
The ammeter test gives a better indication of element life
than the ohmmeter test. This is because the ohm reading of a
worn element is only slightly higher than the reading of a
new one. The ammeter checks all the elements with a single
reading that is easier to interpret than an ohmmeter reading
for each element.
You can also take separate ammeter readings of individual
relays and their elements.
Sincerely,
Arnold Howard
Paragon Industries, L.P., Mesquite, Texas USA
ahoward@paragonweb.com / www.paragonweb.com
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