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panasonic computer controlled microwave kiln?

updated tue 7 dec 04

 

Linda Knapp on wed 1 dec 04


A quick search finds: http://www.gizmodo.com/gadgets/home-entertainment/

BJ Clark wrote:

> I can't read Japanese, so I don't really have any details (maybe
> someone can translate for us), but supposedly Panasonic just came out
> with a Computer Controlled Kiln that uses Microwaves. The site has some
> pics of some nice cups right on the top. I'm guessing this is some sort
> of replacement for an Electric Kiln, but I don't have any details.
> The site is at: http://www.sense.panasonic.co.jp/tougei/index.html
>
> Anyone have any details on this? Sounds pretty interesting. Not just
> because it's some new kiln, but from Panasonic? Very interesting.
> Thanks for any help anyone can provide,
> BJ Clark
> Grand Junction, CO
>
> ______________________________________________________________________________
>
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
> melpots@pclink.com.

BJ Clark on wed 1 dec 04


I can't read Japanese, so I don't really have any details (maybe
someone can translate for us), but supposedly Panasonic just came out
with a Computer Controlled Kiln that uses Microwaves. The site has some
pics of some nice cups right on the top. I'm guessing this is some sort
of replacement for an Electric Kiln, but I don't have any details.
The site is at: http://www.sense.panasonic.co.jp/tougei/index.html

Anyone have any details on this? Sounds pretty interesting. Not just
because it's some new kiln, but from Panasonic? Very interesting.
Thanks for any help anyone can provide,
BJ Clark
Grand Junction, CO

BJ Clark on thu 2 dec 04


Yup, that's where I found it. Not very much information there though so
I turned here.

Thanks everyone on the information. Very cool stuff.
Gotta love this list.

:D

-BJ
In frigid Western Colorado



On Dec 1, 2004, at 11:13 PM, Linda Knapp wrote:

> A quick search finds:
> http://www.gizmodo.com/gadgets/home-entertainment/
>
> BJ Clark wrote:
>
>> I can't read Japanese, so I don't really have any details (maybe
>> someone can translate for us), but supposedly Panasonic just came out
>> with a Computer Controlled Kiln that uses Microwaves. The site has
>> some
>> pics of some nice cups right on the top. I'm guessing this is some
>> sort
>> of replacement for an Electric Kiln, but I don't have any details.
>> The site is at: http://www.sense.panasonic.co.jp/tougei/index.html
>>
>> Anyone have any details on this? Sounds pretty interesting. Not just
>> because it's some new kiln, but from Panasonic? Very interesting.
>> Thanks for any help anyone can provide,
>> BJ Clark
>> Grand Junction, CO
>>
>> ______________________________________________________________________
>> ________
>>
>> Send postings to clayart@lsv.ceramics.org
>>
>> You may look at the archives for the list or change your subscription
>> settings from http://www.ceramics.org/clayart/
>>
>> Moderator of the list is Mel Jacobson who may be reached at
>> melpots@pclink.com.
>
> _______________________________________________________________________
> _______
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
> melpots@pclink.com.
>

Bob Masta on thu 2 dec 04


I don't read Japanese either, but I do know a bit about
microwaves. They will only heat up things with polar
molecules (like water) that can be dragged back and forth
by the fields. Industrially, there are combination
microwave/gas kilns that use microwaves initially to
force-dry the wares and do some preheating in the
process, but the gas (or conventional electric) has
to cut in when the water is gone. There are also
kilns that use silicon carbide "susceptors" that
heat up by absorbing microwaves, and radiate heat
to the rest of the kiln. A quick Google on "microwave kiln"
turned up one (also Japanese) that works by using the
microwaves to heat the walls of the kiln, which then heat
the wares.

On a side note:
There have been suggestions on this list in the past that
iron-bearing glazes might heat up in a kitchen microwave,
but I am skeptical due to the lack of mobility of the iron
immobilized in the glaze matrix. The only other way I
can think of that iron glazes could heat up in a microwave
would be by induction heating, if there was enough iron
in a continuous conductive mass. I doubt this is ever
going to be the case in a normal glaze, but it might be
a good subject for experimentation!

Best regards,

Bob Masta

potsATdaqartaDOTcom

Lee Love on thu 2 dec 04


On 2004/12/02 4:37:12, clayart@lsv.ceramics.org wrote:

> The site is at: http://www.sense.panasonic.co.jp/tougei/index.html

> Thanks for any help anyone can provide,

* I used tinyurl.com to shorten the link (translation via bablefish
to translate the spec sheet) :

http://tinyurl.com/4xazm

$15,000.00 for this little puppy.


Lee In Mashiko, Japan
*

May Luk on thu 2 dec 04


Hi BJ;

I saw how this microwave process worked in a workshop in Sept in Glasgow
School of Art. It was a presentation by potters from Toki, Japan. The theme
of the presentation was 'past, present and future of Japanese pottery'.

The microwave kiln was the future part of the talk. I saw some diagram whic=
h
explained the working of the microwave kiln. It can fire bisque, earthenwar=
e
and stoneware/ porcelain and the glaze is supposingly the same quality. The
samples I've seen are only bright colours oxidation glaze types. Apparently
some industrial ceramics companies are using it now. One main advantage is
energy efficiency. I didn't take any note, but I think the firing time was
either 2 hours or 4 hours - very fast. They also claim that you can do al=
l
sort of effects in 'craft' glaze as I had asked about controlled cool and
special effect glazes.

An actual microwave kiln was not brought to Scotland. The demonstrations
that I saw was a light weight foam box lookalike where a small sake cup can
be fit into it. I overheard it was silicon carbide inside to make the
container. This container was then put into a household microwave for a fe=
w
minute. Ding! and it was sufficient to fire some onglaze decoration. [He pu=
t
a piece of paper in the cup while cooling - he can judge by the temperature
by looking at how the paper fired up] This container only cost about =A325.
There are hobby home version kiln. It's made by Panasonic. [The one that yo=
u
saw in the web site - the site said the microwave dries the ware for you -
like a defrost setting? ;-) ] They are not very expensive. I don't remember
exactly how much as he was quoting yen and then some translations and
conversions back and forth and the message was lost.

They also talked about ceramic recycling. They have a process where they ca=
n
recycle 99% of old dishes into new production. All very innovative.

I had come across the business card of the company just last week, but now =
I
can't find it. I can track down the info if you want it. They are keen to
present the technology outside of Japan.

Best Regards
May
London, UK

John K Dellow on thu 2 dec 04


I got my wife to have a look at the page and it is indeed a small kiln.

The link under the picture of the kiln gives the specks.

It will fire to 1250C in 3 hours ,but with a cooling cycle of 18 hours

John

John Dellow "the flower pot man"
From the land down under
Home Page http://www.welcome.to/jkdellow
http://digitalfire.com/education/people/dellow/

Lee Love on fri 3 dec 04


BJ Clark wrote:

> Anyone have any details on this? Sounds pretty interesting. Not just
> because it's some new kiln, but from Panasonic?

I didn't address this in my last post.
Panasonic/National/Matsushita makes all sorts of products in Japan,
from folding bicycles to houses. The houses are called Panahomes.

--
Lee in Mashiko, Japan http://mashiko.org
http://www.livejournal.com/users/togeika/ WEB LOG
http://public.fotki.com/togeika/ Photos!

Rod Wuetherick on fri 3 dec 04


Bob,

Could you explain why a celadon on porcelain is cooler (much) from the
microwave than a temmoku on porcelain?

Just a practical observation...

I confess I don't know the science but I do have first hand (ouch)
experience...

Cheers,
Rod

On a side note:
There have been suggestions on this list in the past that
iron-bearing glazes might heat up in a kitchen microwave,
but I am skeptical due to the lack of mobility of the iron
immobilized in the glaze matrix. The only other way I
can think of that iron glazes could heat up in a microwave
would be by induction heating, if there was enough iron
in a continuous conductive mass. I doubt this is ever
going to be the case in a normal glaze, but it might be
a good subject for experimentation!

Andrew Lubow on fri 3 dec 04


If you don't mind doing some copying and pasting you can find a free =
internet translator for Japanese to English @ =
http://dictionary.reference.com/translate/text.htmlerence.com/translate/text.html>

Andy Lubow
"Live each day like it was going to be your last. Someday you'll be =
right" Benny Hill
----- Original Message -----=20
From: BJ Clark=20
To: CLAYART@LSV.CERAMICS.ORG=20
Sent: Wednesday, December 01, 2004 2:37 PM
Subject: Panasonic Computer Controlled Microwave Kiln?


I can't read Japanese, so I don't really have any details (maybe
someone can translate for us), but supposedly Panasonic just came out
with a Computer Controlled Kiln that uses Microwaves. The site has =
some
pics of some nice cups right on the top. I'm guessing this is some =
sort
of replacement for an Electric Kiln, but I don't have any details.
The site is at: =
http://www.sense.panasonic.co.jp/tougei/index.htmlonic.co.jp/tougei/index.html>

Anyone have any details on this? Sounds pretty interesting. Not just
because it's some new kiln, but from Panasonic? Very interesting.
Thanks for any help anyone can provide,
BJ Clark
Grand Junction, CO

=
_________________________________________________________________________=
_____
Send postings to =
clayart@lsv.ceramics.org

You may look at the archives for the list or change your subscription
settings from =
http://www.ceramics.org/clayart/

Moderator of the list is Mel Jacobson who may be reached at =
melpots@pclink.com.

Arnold Howard on fri 3 dec 04


I first heard of a microwave kiln in 1990. It was a small container placed
inside a microwave oven and was used for fusing glass.

Sincerely,

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

From: "Lee Love"
> BJ Clark wrote:
>
>> Anyone have any details on this? Sounds pretty interesting. Not just
>> because it's some new kiln, but from Panasonic?
>
> I didn't address this in my last post.
> Panasonic/National/Matsushita makes all sorts of products in Japan,
> from folding bicycles to houses. The houses are called Panahomes.

Bob Masta on sat 4 dec 04


> Date: Fri, 3 Dec 2004 00:48:42 -0800
> From: Rod Wuetherick
> Subject: Re: Panasonic Computer Controlled Microwave Kiln?
>
> Bob,
>
> Could you explain why a celadon on porcelain is cooler
> (much) from the microwave than a temmoku on porcelain?
>
> Just a practical observation...
>
> I confess I don't know the science but I do have first hand
> (ouch) experience...
>
> Cheers,
> Rod

Rod, maybe *I'm* the one that doesn't know the science!

I assumed that mobility of the polar molecules was
required for heating. In a kitchen microwave oven, the
actual heat is produced by friction from the motion of
water or other polar molecules being dragged back and
forth by the fields. That's why the popcorn gets hot
but the dry paper bag doesn't.

So the question is just how mobile any molecule can be
while bound in a ceramic matrix, at least at normal
temperatures. From your observations, whatever mobility
there is must be enough!

The other possibility is that there is some other effect
going on here, such as inductive heating. That's
essentially no different than the heating that goes on
when electrons flow through a resistive wire like a kiln
element, except that the electrons are being dragged
around in little circles by external fields instead of up
and down the wire by the mains voltage.

But you need a certain amount of conductivity for the
electrons to move, and I assume that at normal
temperatures the glaze is a really good insulator.
(Consider all the high-voltage insulators covered in
iron-bearing Albany slip.) So the effect you note
must be either more mobility than I gave credence
to, or (per Monty Python) "something completely
different". I'll report back if I can dig up any
info on this.

For everyone interested in the Japanese microwave kiln,
note that the apparent mode of operation is that the
microwaves heat up the walls, which radiate to the wares.
The claim is that this gives more even heating. That
might be true, but that certainly wouldn't be a good
reason to use microwaves this way.

That's because microwave heating is terribly inefficient
compared to conventional elements, which are 100%
efficient (all the power is converted to heat in the
chamber). Microwave ovens are typically only 50-60%
efficient because the mains power has to be converted to
microwaves first, a lossy process that sends waste heat
to the surroundings. The only reason a kitchen microwave
is more efficient than a conventional oven is that inside
the microwave chamber only the food is heated, whereas
the conventional oven has to heat the entire chamber.

This "heat only the contents" effect is not what is
going on in the microwave kiln. As far as I can tell,
it uses normal radiant/convection heat from the walls,
which are heated by the microwaves. Seems to me you
could put conventional elements inside the walls and
get the same even heating, if that was really an
issue, and get nearly twice the efficiency. (Or use a
saggar in a regular kiln.)

There also seems to be some mystique about heating speed.
I confess I see no advantage to this for potters; we
normally need to limit firing rates anyway. If we really
needed faster heating for some strange purpose,
conventional elements would be the way to go, or possibly
silicon carbide. (For really high speed heating, the
elements have to be much hotter than the contents to
radiate heat faster, and silicon carbide could handle
higher temperatures.)

So I'm mystified as to what others find so appealing
about microwave kilns. Or who exactly Panasonic regards
as their market.

Best regards,










Bob Masta

potsATdaqartaDOTcom

Ron Roy on sat 4 dec 04


Hi Rod,

I make dinnerware with a tenmoku glaze (7.5% iron) on porcelain and have
tested and used it extensivly in the microwave oven and have not found any
extra heating.

The first step in answering the question would be to soak some unglazed
porcelain for a few days and test it in the microwave to see if it is
absorbing water.

Many tenmokus are crazed by the way - this could be a factor in water being
absorbed into underfired clay.

An interesting question but is not the fault of the glaze in this situation
based on my experience.

RR


>Could you explain why a celadon on porcelain is cooler (much) from the
>microwave than a temmoku on porcelain?
>
>Just a practical observation...
>
>I confess I don't know the science but I do have first hand (ouch)
>experience...
>
>Cheers,
>Rod
>
>On a side note:
>There have been suggestions on this list in the past that
>iron-bearing glazes might heat up in a kitchen microwave,
>but I am skeptical due to the lack of mobility of the iron
>immobilized in the glaze matrix. The only other way I
>can think of that iron glazes could heat up in a microwave
>would be by induction heating, if there was enough iron
>in a continuous conductive mass. I doubt this is ever
>going to be the case in a normal glaze, but it might be
>a good subject for experimentation!

Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513

Mike Martino on sun 5 dec 04


Hi Bob,
I first saw this kiln type because Panasonic sent a pamphlet to my teacher
asking him to participate in a trial for the thing, offering it at a
discounted price to those who joined the trial. At that price, it is still
$9,500. Full price was $15,000.
We talked about it a bit, wondered about evenness of temp with a 3 hour
firing time, and all that. He thought it might be a good test/emergency
kiln. But the pamphlet said it only fired to 1250C, so that was the deciding
factor, since he fires to 1300C about half the time.

When I went to Mashiko this past fall, Furuki san had one of these and was
using it. Turns out he'd been using one since they started designing the
thing and he'd seen all the phases of production, all the problems solved
(well, most anyway). In it's current form, he was quite happy with what it
could do. I commented on the temp. limit. He said the thing would fire to
1400C easily, could be programmed with any number of auto firing schedules,
as well as whatever custom schedules anyone could come up with. By the way,
though the thing fires the pots in 3 hours evenly, it takes around 12 to
cool(or more), just like any other kiln.

Anyway, with the current model and its size, Panasonic is not aiming at
studio owning professionals, but rather home hobbyists (there is something
of a boom of amateur potters these days here), and mostly the ones living in
small spaces in large cities, and in apartment buildings. People like this
currently have no chance of owning their own kiln, and it costs a fortune to
use someone elses. This kiln would fit comfortably in a Tokyo apartment.
Furuki san also said it didn't radiate much heat. The last problem they were
working to solve was venting gases for people who would want put in
combustible material for reduction, which apparently the thing will not
mind. All that said, I think the price will need to come down a bit before
people start biting.

It looked like the kilns at the Takasago website were aiming more for a high
volume ceramics production environment, but not necessarily at potting per
se.


^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
mike martino
in taku, japan

muchimi@potteryofjapan.com
www.potteryofjapan.com

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG]On Behalf Of Bob Masta
Sent: Sunday, December 05, 2004 1:27 AM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: Panasonic Computer Controlled Microwave Kiln?


> Date: Fri, 3 Dec 2004 00:48:42 -0800
> From: Rod Wuetherick
> Subject: Re: Panasonic Computer Controlled Microwave Kiln?
>
> Bob,
>
> Could you explain why a celadon on porcelain is cooler
> (much) from the microwave than a temmoku on porcelain?
>
> Just a practical observation...
>
> I confess I don't know the science but I do have first hand
> (ouch) experience...
>
> Cheers,
> Rod

Rod, maybe *I'm* the one that doesn't know the science!

I assumed that mobility of the polar molecules was
required for heating. In a kitchen microwave oven, the
actual heat is produced by friction from the motion of
water or other polar molecules being dragged back and
forth by the fields. That's why the popcorn gets hot
but the dry paper bag doesn't.

So the question is just how mobile any molecule can be
while bound in a ceramic matrix, at least at normal
temperatures. From your observations, whatever mobility
there is must be enough!

The other possibility is that there is some other effect
going on here, such as inductive heating. That's
essentially no different than the heating that goes on
when electrons flow through a resistive wire like a kiln
element, except that the electrons are being dragged
around in little circles by external fields instead of up
and down the wire by the mains voltage.

But you need a certain amount of conductivity for the
electrons to move, and I assume that at normal
temperatures the glaze is a really good insulator.
(Consider all the high-voltage insulators covered in
iron-bearing Albany slip.) So the effect you note
must be either more mobility than I gave credence
to, or (per Monty Python) "something completely
different". I'll report back if I can dig up any
info on this.

For everyone interested in the Japanese microwave kiln,
note that the apparent mode of operation is that the
microwaves heat up the walls, which radiate to the wares.
The claim is that this gives more even heating. That
might be true, but that certainly wouldn't be a good
reason to use microwaves this way.

That's because microwave heating is terribly inefficient
compared to conventional elements, which are 100%
efficient (all the power is converted to heat in the
chamber). Microwave ovens are typically only 50-60%
efficient because the mains power has to be converted to
microwaves first, a lossy process that sends waste heat
to the surroundings. The only reason a kitchen microwave
is more efficient than a conventional oven is that inside
the microwave chamber only the food is heated, whereas
the conventional oven has to heat the entire chamber.

This "heat only the contents" effect is not what is
going on in the microwave kiln. As far as I can tell,
it uses normal radiant/convection heat from the walls,
which are heated by the microwaves. Seems to me you
could put conventional elements inside the walls and
get the same even heating, if that was really an
issue, and get nearly twice the efficiency. (Or use a
saggar in a regular kiln.)

There also seems to be some mystique about heating speed.
I confess I see no advantage to this for potters; we
normally need to limit firing rates anyway. If we really
needed faster heating for some strange purpose,
conventional elements would be the way to go, or possibly
silicon carbide. (For really high speed heating, the
elements have to be much hotter than the contents to
radiate heat faster, and silicon carbide could handle
higher temperatures.)

So I'm mystified as to what others find so appealing
about microwave kilns. Or who exactly Panasonic regards
as their market.

Best regards,










Bob Masta

potsATdaqartaDOTcom

____________________________________________________________________________
__
Send postings to clayart@lsv.ceramics.org

You may look at the archives for the list or change your subscription
settings from http://www.ceramics.org/clayart/

Moderator of the list is Mel Jacobson who may be reached at
melpots@pclink.com.

John Hesselberth on sun 5 dec 04


>> On a side note:
>> There have been suggestions on this list in the past that
>> iron-bearing glazes might heat up in a kitchen microwave,

Hi Rod,

I have tested glazes with up to 15% RIO and cannot detect any
appreciable microwave heating IF the clay body is mature (in my tests
it was about 1.5-2.0% absorption). The only time I have been able to
get microwave heating of an empty ceramic pot (with a full pot in the
microwave to prevent problems) is when the clay body is above 3%
absorption. Earthenware at 10 or 12% absorption is where it is easiest
to demonstrate the effect, but it can happen on immature stoneware
also. Then it will/can happen if the pot has been through a dishwasher
a few times (or otherwise been soaked in water) and is not fully
encased in a defect free glaze.

I believe Dave Finkelnburg has tested this also with similar results.

Regards,

John

John Hesselberth
http://www.frogpondpottery.com
http://www.masteringglazes.com

Bob Masta on mon 6 dec 04


Mike Martino writes:


> Anyway, with the current model and its size, Panasonic is
> not aiming at studio owning professionals, but rather home
> hobbyists (there is something of a boom of amateur potters
> these days here), and mostly the ones living in small spaces
> in large cities, and in apartment buildings. People like
> this currently have no chance of owning their own kiln, and
> it costs a fortune to use someone elses. This kiln would fit
> comfortably in a Tokyo apartment. Furuki san also said it
> didn't radiate much heat. The last problem they were working
> to solve was venting gases for people who would want put in
> combustible material for reduction, which apparently the
> thing will not mind. All that said, I think the price will
> need to come down a bit before people start biting.
>

Mike, a microwave kiln *has* to radiate more heat than a
similar kiln with conventional elements, because about half
of the heat is lost from the microwave conversion circuitry
which is outside the chamber and can't be insulated... the
normal idea is to try to keep the circuitry as cool as possible,
which is why your kitchen microwave has a fan to send that
heat into the room. The best way to build a small kiln for
apartment use would be to use conventional elements and
extra insulation.

Best regards,



Bob Masta

potsATdaqartaDOTcom