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old kilns vs computer kilns

updated tue 18 dec 07

 

mel jacobson on thu 13 dec 07


just a side bar note.

older kilns can be re started to
control the cooling.

just push the button on the kiln sitter.
fire with the use of an alarm clock.
(just make sure you know you are no longer
in assumed fail safe.)

the new kilns are wonderful. and, they
are very expensive for someone that is
not ready for that commitment, or if your
older kiln is still working.

it is like wayne has said...if you have never
driven a race car...stick with your old ford.

but, control of cooling is a very big issue and
it cannot be ignored.
mel
it is like the guy being over heard filling his boat
with gas...`hell, it's just $480 bucks a day to run her.`

from: mel/minnetonka.mn.usa
website: http://www.visi.com/~melpots/

Clayart page link: http://www.visi.com/~melpots/clayart.html

David Hendley on thu 13 dec 07


I bisque fire in a "semi-antique" Paragon, as Arnold Howard
called it when he saw a photograph.
I always turn it on again when it is cooling - Right at that point
when it is dull red, to make sure large pieces are a reasonably
consistent temperature before they go through the phase
change.

I usually hear the kiln sitter fall and turn off the kiln. I
immediately go in and turn the 3 knobs to 'off', reset the
kiln setter, and add more hours to the timer.
Then, 3 hours later, I go back to the shop (it is usually evening
by then) and turn all knobs to 'high' for half an hour. This
evens up the outside of the kiln, which cools faster than the
center of the kiln. And my kiln has 3" thick walls, 1/2"
more than many kilns.

I sometimes feel like a fool for trudging over to the shop at
various times in the early morning just to turn up a kiln
knob. I mean, come on, I'm a professional potter - I should
have up-to-date equipment. Then I think about the people
who get up early in the morning and pay money to walk
around a track for exercise and realize I'm getting my
exercise for free. Also, it's hard to feel up-to-date when
you make pottery by hand and fire a wood-fired kiln.

David Hendley
Maydelle, Texas
david(at)farmpots(dot)com
http://www.farmpots.com



----- Original Message -----
> older kilns can be re started to
> control the cooling.
>
> just push the button on the kiln sitter.
> fire with the use of an alarm clock.
> (just make sure you know you are no longer
> in assumed fail safe.)
>
> the new kilns are wonderful. and, they
> are very expensive for someone that is
> not ready for that commitment, or if your
> older kiln is still working.
>
> it is like wayne has said...if you have never
> driven a race car...stick with your old ford.
>
> but, control of cooling is a very big issue and
> it cannot be ignored.
> mel

Maggie Jones on thu 13 dec 07


"I sometimes feel like a fool for trudging over to the shop at
> various times in the early morning just to turn up a kiln
> knob. I mean, come on, I'm a professional potter - I should
> have up-to-date equipment. Then I think about the people
> who get up early in the morning and pay money to walk
> around a track for exercise and realize I'm getting my
> exercise for free."

...for free?...I figure I'm getting paid to do that!
M


On Thu, 13 Dec 2007 11:40:35 -0600 David Hendley
writes:
> I bisque fire in a "semi-antique" Paragon, as Arnold Howard
> called it when he saw a photograph.
> I always turn it on again when it is cooling - Right at that point
> when it is dull red, to make sure large pieces are a reasonably
> consistent temperature before they go through the phase
> change.
>
> I usually hear the kiln sitter fall and turn off the kiln. I
> immediately go in and turn the 3 knobs to 'off', reset the
> kiln setter, and add more hours to the timer.
> Then, 3 hours later, I go back to the shop (it is usually evening
> by then) and turn all knobs to 'high' for half an hour. This
> evens up the outside of the kiln, which cools faster than the
> center of the kiln. And my kiln has 3" thick walls, 1/2"
> more than many kilns.
>
> I sometimes feel like a fool for trudging over to the shop at
> various times in the early morning just to turn up a kiln
> knob. I mean, come on, I'm a professional potter - I should
> have up-to-date equipment. Then I think about the people
> who get up early in the morning and pay money to walk
> around a track for exercise and realize I'm getting my
> exercise for free. Also, it's hard to feel up-to-date when
> you make pottery by hand and fire a wood-fired kiln.
>
> David Hendley
> Maydelle, Texas
> david(at)farmpots(dot)com
> http://www.farmpots.com
>
>
>
> ----- Original Message -----
> > older kilns can be re started to
> > control the cooling.
> >
> > just push the button on the kiln sitter.
> > fire with the use of an alarm clock.
> > (just make sure you know you are no longer
> > in assumed fail safe.)
> >
> > the new kilns are wonderful. and, they
> > are very expensive for someone that is
> > not ready for that commitment, or if your
> > older kiln is still working.
> >
> > it is like wayne has said...if you have never
> > driven a race car...stick with your old ford.
>
> > but, control of cooling is a very big issue and
> > it cannot be ignored.
> > mel
>
>
_________________________________________________________________________
_____
> Clayart members may send postings to: clayart@lsv.ceramics.org
>
> You may look at the archives for the list, post messages, or change
> your
> subscription settings here: http://www.acers.org/cic/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
> melpots2@visi.com
>
>

Hank Murrow on thu 13 dec 07


On Dec 13, 2007, at 1:39 PM, Mike wrote:

> This is going a bit off here, but why do the bulk of electric kilns
> only
> have 2 1/2 to 3 inches of brick to insulate them? Is it purely an
> initial cost issue? A friend of mine recently (a little over a year
> ago)
> bought automatic computer controlled electric that he fires to cone
> 8 -
> 10 with. He calculated his firing cost at about 900 yen per firing,
> that's about 8 bucks. And electricity here is really expensive. I know
> that the kiln was not cheap, probably about 6,000 dollars, but it
> has 9
> inches of insulation all around, and the elements are about 4mm thick.
> You can touch the outside of the kiln at peak temp, and he's said it
> cools really, really slow.

Well Mike;

You get what you pay for. I see potters pulling up to unload their
wares for a big pottery show in an intercooled turbo Volvo wagon
($32,000 approx.) while i KNOW that they fire in a 9" brick kiln that
costs $200 to fire. I pull up in my Toyota Corolla($8000 w. 45,000
miles) and unload pots fired in my Doorless FiberKiln, which fires
the same load for $22 including a soak during cooling in oxidation. A
matter of style I suppose. It is strange that the electric offerings
are so much alike here.

I got some really wonderful shinos from my last firing!

Cheers, Hank
www.murrow.biz/hank

John Rodgers on fri 14 dec 07


Arnold,

My old Crusader had a fiber layer between the outer stainless steel
jacket and the bricks. I have no idea how effective that was. But the
kiln would go to cone 10 or better with no sweat. Performed nicely, but
was definitely a "manually" controlled kiln all the way. I have no idea
if the extra blanket increased efficiency or not. There are energy flow
considerations when one builds a kiln, and I'm sure engineers try to
deal with this by designing for the optimum energy flow from inside the
kiln to the outside. If the flow is to efficient, then it is difficult
to get the kiln up to temperature because of the rate of heat loss thus
increasing fuel consumption (electricity, gas, whatever. . On the other
hand, if there is a large mass of insulating bricks, it takes longer to
heat them up to get the kiln to temperature. and therefore takes more
energy. Then when cooling, it is difficult to cool because of the energy
in that mass. Problems for the engineers.

John Rodgers
Chelsea, AL

Regards,

John Rodgers

Arnold Howard wrote:
> From: "Mike"
>> This is going a bit off here, but why do the bulk of
>> electric kilns only
>> have 2 1/2 to 3 inches of brick to insulate them? Is it
>> purely an
>> initial cost issue?
>
> Kiln manufacturers are happy to make exactly what potters
> demand. If you want thicker walls, we will make them.
>
> We make a square, top-loading kiln with 2 1/2" brick walls
> and 2" of ceramic fiber block insulation. Total wall
> thickness is 4 1/2". We sell very few of those. People
> prefer the lower-priced "round kilns," as we call them in
> the factory (kilns with 7, 8, 10, or 12 sides). Round kilns
> are typically built with a single wall of bricks.
>
> European round kilns have a fiber blanket wrapped around the
> brick walls under the steel case. One drawback of that
> design is that the fiber blanket shrinks with age.
> Nevertheless, that is a viable way to add insulation to a
> round kiln. Does anyone want it?
>
> Sincerely,
>
> Arnold Howard
> Paragon Industries, L.P., Mesquite, Texas USA
> ahoward@paragonweb.com / www.paragonweb.com
>
> ______________________________________________________________________________
>
> Clayart members may send postings to: clayart@lsv.ceramics.org
>
> You may look at the archives for the list, post messages, or change your
> subscription settings here: http://www.acers.org/cic/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
> melpots2@visi.com
>
>

Larry Kruzan on fri 14 dec 07


Yep! In my studio built 100 cf gas kiln I have 9" IFB walls and 4 1/2" IFB
arch with 4" of fiber on top of that - Pretty efficient unit that does a
cone 10 firing, with a moderate reduction on around 35 gallons of propane.
Then I go to my electric kilns 2 23" with 3" walls and one 18" with 2 1/2"
walls and wonder why.............


Larry Kruzan
Lost Creek Pottery
www.lostcreekpottery.com





-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of Arnold Howard
Sent: Friday, December 14, 2007 9:18 AM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: [CLAYART] old kilns vs computer kilns

From: "Mike"
> This is going a bit off here, but why do the bulk of
> electric kilns only
> have 2 1/2 to 3 inches of brick to insulate them? Is it
> purely an
> initial cost issue?

Kiln manufacturers are happy to make exactly what potters
demand. If you want thicker walls, we will make them.

We make a square, top-loading kiln with 2 1/2" brick walls
and 2" of ceramic fiber block insulation. Total wall
thickness is 4 1/2". We sell very few of those. People
prefer the lower-priced "round kilns," as we call them in
the factory (kilns with 7, 8, 10, or 12 sides). Round kilns
are typically built with a single wall of bricks.

European round kilns have a fiber blanket wrapped around the
brick walls under the steel case. One drawback of that
design is that the fiber blanket shrinks with age.
Nevertheless, that is a viable way to add insulation to a
round kiln. Does anyone want it?

Sincerely,

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

____________________________________________________________________________
__
Clayart members may send postings to: clayart@lsv.ceramics.org

You may look at the archives for the list, post messages, or change your
subscription settings here: http://www.acers.org/cic/clayart/

Moderator of the list is Mel Jacobson who may be reached at
melpots2@visi.com

Maurice Weitman on fri 14 dec 07


At 09:18 -0600 on 12/14/07, Arnold Howard wrote:
>Kiln manufacturers are happy to make exactly what potters
>demand. If you want thicker walls, we will make them.
>[...]
>European round kilns have a fiber blanket wrapped around the
>brick walls under the steel case. One drawback of that
>design is that the fiber blanket shrinks with age.
>Nevertheless, that is a viable way to add insulation to a
>round kiln. Does anyone want it?

It depends what your definition of "want" is, Arnold.

Obviously, your company is competing with several others and many
potters make choices using price as their main criterion.

As you may recall, when I was shopping for my 10 cu.ft. electric kiln
three years ago, I looked at most available models and their options.

I chose Bailey's top-loader "round" kiln. One of its features that
made me choose them was its insulation (2.5" IFB and 1" Fiberboard).

I paid about $3,000 for the kiln and furniture, delivered to
California. I could have saved $500 to $1,000 by buying another
brand with less insulation.

Although Axner's kiln had 3" brick with 1" fiber insulation, I chose
the Bailey for its (apparent) superior construction (Axner's was a
spruced-up Olympic which scared me) and features: floor element,
Barrett controller AND Kiln Sitter, etc.

(I have been very happy with the Bailey... it's performed very well.)

If I had the choice, I would have paid more for even more insulation.
I have since added more to the bottom and lid, and when I have the
time, I'll add more to the sides as well, even though it means having
to buy or make a new stainless shell.

Three years ago, energy prices weren't quite as high, nor were the
prospects as strong as they are today for prices to continue to rise
for a long time to come.

I will also do a bit of a plea for us all (potters and kiln
manufacturers) to spend the extra money to use less energy.

And I think that it would be good business to take the lead in
making, and heavily marketing, highly efficient kilns, and even
including the added insulation (or other energy-saving devices) at
cost.

And dare I suggest that kiln manufacturers should take the lead in
educating their customers on the need and benefits of a more
efficient kiln?

If anyone thinks that energy prices will ever be lower than they are
today, and that they won't continue to rise, I've got a bridge to
sell you.

Regards,
Maurice

Arnold Howard on fri 14 dec 07


From: "Mike"
> This is going a bit off here, but why do the bulk of
> electric kilns only
> have 2 1/2 to 3 inches of brick to insulate them? Is it
> purely an
> initial cost issue?

Kiln manufacturers are happy to make exactly what potters
demand. If you want thicker walls, we will make them.

We make a square, top-loading kiln with 2 1/2" brick walls
and 2" of ceramic fiber block insulation. Total wall
thickness is 4 1/2". We sell very few of those. People
prefer the lower-priced "round kilns," as we call them in
the factory (kilns with 7, 8, 10, or 12 sides). Round kilns
are typically built with a single wall of bricks.

European round kilns have a fiber blanket wrapped around the
brick walls under the steel case. One drawback of that
design is that the fiber blanket shrinks with age.
Nevertheless, that is a viable way to add insulation to a
round kiln. Does anyone want it?

Sincerely,

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

James and Sherron Bowen on fri 14 dec 07


Would it be useful for those of us with a supply of fiber to wrap our round
kilns outside of the steel shell?
JB

----- Original Message -----
From: "Arnold Howard"
To:
Sent: Friday, December 14, 2007 8:18 AM
Subject: Re: old kilns vs computer kilns

Ric Swenson on fri 14 dec 07


Wrapping the steel shell with fiber material will likely cause premature de=
terioration of the steel due to excess exposure to moisture during warm up =
and extreme heat later in firings. IMHO.
=20
Arnold?
=20
Ric
=20
=20
_________________________________________________________________
The best games are on Xbox 360. Click here for a special offer on an Xbox =
360 Console.
http://www.xbox.com/en-US/hardware/wheretobuy/=

Steve Slatin on fri 14 dec 07


Arnold --

I'm not surprised that you don't sell too many of the
highly insulated kilns. People tend to buy what they
used at their school, so fashions don't change too
quickly. People will switch, but they have to have
confidence in what they're considering buying.

When I wanted to buy a kiln I tried to find out what
the difference would be in electrical consumption
if I got a highly insulated kiln. No one seemed to
have that info, and I got a 3" brick kiln.

I think if a reputable manufacturer (I'm not pressing
you here, but you fit both the noun and the
adjective) were to run some tests and publish
the results, you might see more people making
choices based on the facts -- whatever they
may be.

Best wishes -- Steve S


Arnold Howard wrote:
From: "Mike"
> This is going a bit off here, but why do the bulk of
> electric kilns only
> have 2 1/2 to 3 inches of brick to insulate them? Is it
> purely an
> initial cost issue?

Kiln manufacturers are happy to make exactly what potters
demand. If you want thicker walls, we will make them.

We make a square, top-loading kiln with 2 1/2" brick walls
and 2" of ceramic fiber block insulation. Total wall
thickness is 4 1/2". We sell very few of those. People
prefer the lower-priced "round kilns," as we call them in
the factory (kilns with 7, 8, 10, or 12 sides). Round kilns
are typically built with a single wall of bricks.

European round kilns have a fiber blanket wrapped around the
brick walls under the steel case. One drawback of that
design is that the fiber blanket shrinks with age.
Nevertheless, that is a viable way to add insulation to a
round kiln. Does anyone want it?

---------------------------------
Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now.

Mike on fri 14 dec 07


This is going a bit off here, but why do the bulk of electric kilns only
have 2 1/2 to 3 inches of brick to insulate them? Is it purely an
initial cost issue? A friend of mine recently (a little over a year ago)
bought automatic computer controlled electric that he fires to cone 8 -
10 with. He calculated his firing cost at about 900 yen per firing,
that's about 8 bucks. And electricity here is really expensive. I know
that the kiln was not cheap, probably about 6,000 dollars, but it has 9
inches of insulation all around, and the elements are about 4mm thick.
You can touch the outside of the kiln at peak temp, and he's said it
cools really, really slow.

Mike
in Taku, Japan

karatsupots.blogspot.com
www.karatsupots.com



David Hendley ????????:
> I bisque fire in a "semi-antique" Paragon, as Arnold Howard
> called it when he saw a photograph.
> I always turn it on again when it is cooling - Right at that point
> when it is dull red, to make sure large pieces are a reasonably
> consistent temperature before they go through the phase
> change.
>
> I usually hear the kiln sitter fall and turn off the kiln. I
> immediately go in and turn the 3 knobs to 'off', reset the
> kiln setter, and add more hours to the timer.
> Then, 3 hours later, I go back to the shop (it is usually evening
> by then) and turn all knobs to 'high' for half an hour. This
> evens up the outside of the kiln, which cools faster than the
> center of the kiln. And my kiln has 3" thick walls, 1/2"
> more than many kilns.
>
> I sometimes feel like a fool for trudging over to the shop at
> various times in the early morning just to turn up a kiln
> knob. I mean, come on, I'm a professional potter - I should
> have up-to-date equipment. Then I think about the people
> who get up early in the morning and pay money to walk
> around a track for exercise and realize I'm getting my
> exercise for free. Also, it's hard to feel up-to-date when
> you make pottery by hand and fire a wood-fired kiln.
>
> David Hendley
> Maydelle, Texas
> david(at)farmpots(dot)com
> http://www.farmpots.com
>
>
>
> ----- Original Message -----
>> older kilns can be re started to
>> control the cooling.
>>
>> just push the button on the kiln sitter.
>> fire with the use of an alarm clock.
>> (just make sure you know you are no longer
>> in assumed fail safe.)
>>
>> the new kilns are wonderful. and, they
>> are very expensive for someone that is
>> not ready for that commitment, or if your
>> older kiln is still working.
>>
>> it is like wayne has said...if you have never
>> driven a race car...stick with your old ford.
>>
>> but, control of cooling is a very big issue and
>> it cannot be ignored.
>> mel
>
> ______________________________________________________________________________
>
> Clayart members may send postings to: clayart@lsv.ceramics.org
>
> You may look at the archives for the list, post messages, or change your
> subscription settings here: http://www.acers.org/cic/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
> melpots2@visi.com
>

William & Susan Schran User on sat 15 dec 07


On 12/14/07 6:35 PM, "Steve Slatin" wrote:

> I think if a reputable manufacturer (I'm not pressing
> you here, but you fit both the noun and the
> adjective) were to run some tests and publish
> the results, you might see more people making
> choices based on the facts -- whatever they
> may be.

Hey Steve, is this what you're looking for?:
http://www.hotkilns.com/brickstudy.pdf


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

Steve Slatin on sat 15 dec 07


Bill --

I have in mind something much simpler. While I cannot
with certainty deny the possibility that the information
there could be used to generate the information prospective
buyers need, I cannot myself obtain that information from
it.

What you'd need to know to make an informed decision
is how much two kilns of otherwise identical dimensions
use in KWH to fire to a given cone, given identical
loads and firing profiles.

Ideally, the test runs could be done at different profiles
as well -- say each kiln fast fire to ^6, turn off would be one
test, each kiln identically slow fired to ^6 and then
with a 30 minute hold at the top, each with
slow fire, hold at the top, and controlled fire down.

The comparisons would show the truth or falsehood to
the theory that 2 1/2 inch brick is cheaper or more
costly than 3", than 3" with an inch of insulating blanket,
etc.

My personal suspicion is that the results will be
significantly different at ^10 than at ^6, and that there
may be a difference on controlled cools as well.

What L*L gives us in that mysteriously titled
column "watts per internal square inch" is tempting
to use for a paper calculation of this, but it's not clear
what the external circumstances are (or how to
convert this value into something useful).


Best wishes -- Steve S

William & Susan Schran User wrote:
On 12/14/07 6:35 PM, "Steve Slatin" wrote:

> I think if a reputable manufacturer (I'm not pressing
> you here, but you fit both the noun and the
> adjective) were to run some tests and publish
> the results, you might see more people making
> choices based on the facts -- whatever they
> may be.

Hey Steve, is this what you're looking for?:
http://www.hotkilns.com/brickstudy.pdf



---------------------------------
Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now.

Mike on sun 16 dec 07


Hello Howard,

Do you know of any information sources which compare initial cost vs.
cost per firing and longevity (of elements, bricks, computer parts,
etc.). Honestly, I don't know for sure but, it seems to me that if
people could compare the overall cost of a kiln over the course of 10 or
15 years and see that the beefy kilns are actually cheaper in the long
run, maybe that would sell them on the idea.
Mike
Just sort of thinking out loud here, certainly not presuming to tell you
your business.

Mike
in Taku, Japan

karatsupots.blogspot.com
www.karatsupots.com



Arnold Howard ????????:
> From: "Mike"
>> This is going a bit off here, but why do the bulk of
>> electric kilns only
>> have 2 1/2 to 3 inches of brick to insulate them? Is it
>> purely an
>> initial cost issue?
>
> Kiln manufacturers are happy to make exactly what potters
> demand. If you want thicker walls, we will make them.
>
> We make a square, top-loading kiln with 2 1/2" brick walls
> and 2" of ceramic fiber block insulation. Total wall
> thickness is 4 1/2". We sell very few of those. People
> prefer the lower-priced "round kilns," as we call them in
> the factory (kilns with 7, 8, 10, or 12 sides). Round kilns
> are typically built with a single wall of bricks.
>
> European round kilns have a fiber blanket wrapped around the
> brick walls under the steel case. One drawback of that
> design is that the fiber blanket shrinks with age.
> Nevertheless, that is a viable way to add insulation to a
> round kiln. Does anyone want it?
>
> Sincerely,
>
> Arnold Howard
> Paragon Industries, L.P., Mesquite, Texas USA
> ahoward@paragonweb.com / www.paragonweb.com
>
> ______________________________________________________________________________
>
> Clayart members may send postings to: clayart@lsv.ceramics.org
>
> You may look at the archives for the list, post messages, or change your
> subscription settings here: http://www.acers.org/cic/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
> melpots2@visi.com
>

Eleanora Eden on mon 17 dec 07


Hi JB,

Here is a post I sent about 5 years ago about my kiln-wrapping job.
The idea that it will degrade the stainless steel might be valid at higher temps,
I don't know about that. I fire ^04-06. The benefits are enormous.

Eleanora


Twelve or thirteen years ago we wrapped my L&L kiln with kaowool and tin
foil and wire. At the time I was told in no uncertain terms that it will wreck the
stainless steel shell. Well we did it anyway because, frankly, that made
no sense to me.

Well, about 3 years ago we took all that off as the top area of kaowool had
been degrading (it is a top-loader) and, no surprise at all, the stainless
steel shell is still in perfect condition. We replaced it with a new
kaowool layer and this time we used masonry cement to make an impervious
outer shell. So my kiln looks like a little missile silo.





>Would it be useful for those of us with a supply of fiber to wrap our round
>kilns outside of the steel shell?
>JB

--
Bellows Falls Vermont
www.eleanoraeden.com