search  current discussion  categories  kilns & firing - misc 

er(electric reduction)

updated fri 21 dec 07

 

David Turner on mon 10 dec 07


Hi again ...it's been 24 hrs and I got loads of e-mails...The only problem
is that I am a slow typist so a quick response to everyone will take awhile.

The process I am working with is TOP SECRET and my lawyer advised me not to
talk in too much detail just yet. (I was just kidding about the TOP SECRET
stuff.)
The main achievement is the reduction of carbonaceous material required to
get a perfectly balanced reducing atmosphere.You might say it is a
convenient solution to potter pollution.The best part of the process for
myself is the increased intimacy with the element of fire. This isn't
Ronco's "set it and forget it"
easy bake oven kind of thing.It's hands on, but very simple and I guess I
just find it totally exciting and lots of fun, and I hope to share it soon.
Thanks for all of the great e-mails.
Does anyone know Al Gore's e-mail address?
David T.

Earl Brunner on mon 10 dec 07


Don't care if it's "secret" or proprietary, if you can't answer the questions regarding solving the problems with electric elements in reduction having a significantly shorter life, then you will have limited success selling them.


----- Original Message ----
From: David Turner
To: CLAYART@LSV.CERAMICS.ORG
Sent: Monday, December 10, 2007 6:38:05 PM
Subject: ER(electric reduction)

Hi again ...it's been 24 hrs and I got loads of e-mails...The only problem
is that I am a slow typist so a quick response to everyone will take awhile.

The process I am working with is TOP SECRET and my lawyer advised me not to
talk in too much detail just yet. (I was just kidding about the TOP SECRET
stuff.)
The main achievement is the reduction of carbonaceous material required to
get a perfectly balanced reducing atmosphere.You might say it is a
convenient solution to potter pollution.The best part of the process for
myself is the increased intimacy with the element of fire. This isn't
Ronco's "set it and forget it"
easy bake oven kind of thing.It's hands on, but very simple and I guess I
just find it totally exciting and lots of fun, and I hope to share it soon.
Thanks for all of the great e-mails.
Does anyone know Al Gore's e-mail address?
David T.

______________________________________________________________________________
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

Charlie Hightower on tue 11 dec 07


I don't know about your TOP SECRET design, but the
best way to build an electric reduction kiln is to use
silicon carbide rod type elements. They are immune to
reduction. Also, they last MUCH longer as well as can
fire much hotter then cone 10 (if you choose).
However, building such a kiln would be very pricey. If
someone could put a line of 5-8 cubic foot top loaders
using Silicon Carbide rods for under $5000 then they
would stand to do very well. I did some electric
reduction utilizing ITC products with mixed success.
Gave it up after building a small gas kiln, but would
surely go back if I never had to change elements.
Firing to cone 6-10 in such a kiln I doubt I ever
would. As far as pollution is concerned my electric
kiln probably pollutes more then my natural gas job
considering the coal burned to power it. Take care and
good luck. Keep us posted please.
--- David Turner wrote:

> Hi again ...it's been 24 hrs and I got loads of
> e-mails...The only problem
> is that I am a slow typist so a quick response to
> everyone will take awhile.
>
> The process I am working with is TOP SECRET and my
> lawyer advised me not to
> talk in too much detail just yet. (I was just
> kidding about the TOP SECRET
> stuff.)
> The main achievement is the reduction of
> carbonaceous material required to
> get a perfectly balanced reducing atmosphere.You
> might say it is a
> convenient solution to potter pollution.The best
> part of the process for
> myself is the increased intimacy with the element of
> fire. This isn't
> Ronco's "set it and forget it"
> easy bake oven kind of thing.It's hands on, but very
> simple and I guess I
> just find it totally exciting and lots of fun, and I
> hope to share it soon.
> Thanks for all of the great e-mails.
> Does anyone know Al Gore's e-mail address?
> David
> T.
>
>
______________________________________________________________________________
> 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
>

Earth Nouveau on sun 16 dec 07


hi charlie
I don't know all the facts about the pollution generated by electric vs gas
firings. The power plants are running whether I fire with gas or electric.
The fossil fuels used up in achieving high temperatures cost more today and
will only cost more in the future. Electricity, on the other hand , soon
will be less expensive and, with the advancing technological developments in
solar cells, will be clean and renewable.
Many potters don't have access to ,or facilities for, a gas kiln. Electric
reduction offers a
way to get copper reds in in a small electric kiln, in a home studio.I hope
to try ER (electric reduction) in my tiny test kiln to see if I can get the
same bright copper reds I now get from my 11 cu ft kiln.
As far as elements go , I have had conversations with several ceramic
engineers about the reasons for failures , and I now believe that it
isn't the reduction that causes the failure in elements. One said that it
was more likely caused by stressing the elements going to cone ten over
and over. As far as my experiments go, I will find out how long the
elements last , in time. All is for the sake of research and the
thrill of pushing the edge of the envelope a little.

David
Turner
On Dec 11, 2007 9:08 AM, Charlie Hightower
wrote:

> I don't know about your TOP SECRET design, but the
> best way to build an electric reduction kiln is to use
> silicon carbide rod type elements. They are immune to
> reduction. Also, they last MUCH longer as well as can
> fire much hotter then cone 10 (if you choose).
> However, building such a kiln would be very pricey. If
> someone could put a line of 5-8 cubic foot top loaders
> using Silicon Carbide rods for under $5000 then they
> would stand to do very well. I did some electric
> reduction utilizing ITC products with mixed success.
> Gave it up after building a small gas kiln, but would
> surely go back if I never had to change elements.
> Firing to cone 6-10 in such a kiln I doubt I ever
> would. As far as pollution is concerned my electric
> kiln probably pollutes more then my natural gas job
> considering the coal burned to power it. Take care and
> good luck. Keep us posted please.
> --- David Turner wrote:
>
> > Hi again ...it's been 24 hrs and I got loads of
> > e-mails...The only problem
> > is that I am a slow typist so a quick response to
> > everyone will take awhile.
> >
> > The process I am working with is TOP SECRET and my
> > lawyer advised me not to
> > talk in too much detail just yet. (I was just
> > kidding about the TOP SECRET
> > stuff.)
> > The main achievement is the reduction of
> > carbonaceous material required to
> > get a perfectly balanced reducing atmosphere.You
> > might say it is a
> > convenient solution to potter pollution.The best
> > part of the process for
> > myself is the increased intimacy with the element of
> > fire. This isn't
> > Ronco's "set it and forget it"
> > easy bake oven kind of thing.It's hands on, but very
> > simple and I guess I
> > just find it totally exciting and lots of fun, and I
> > hope to share it soon.
> > Thanks for all of the great e-mails.
> > Does anyone know Al Gore's e-mail address?
> > David
> > T.
> >
> >
> ______________________________________________________________________________
>
> > 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
> >
>
>
> ______________________________________________________________________________
> 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
>

Charlie Hightower on sun 16 dec 07


David,
The elements build up a protective oxide coating that
when subjected to reduction, gets stripped just like
the oxygen getting stripped from the glaze. If your
interested in building your own electric, I highly
recommend "Electric Kiln Construction For Potters" by
Robert Fournier. Just ignore the section on Asbestos.
The book is older. I have done quite a bit of electric
reduction as well. After reading Nils Lou's book is
when I got started. I contacted him and he helped
greatly. He is a wealth of information and was kind
enough to give me his time. I reduce in a gas now but
as I said may go back down the road. I look forward to
hearing how it goes for you. Good luck!
Charles is Southern Indiana,
where we will be powered by coal for a long time to
come!
--- Earth Nouveau wrote:

> hi charlie
> I don't know all the facts about the pollution
> generated by electric vs gas
> firings. The power plants are running whether I
> fire with gas or electric.
> The fossil fuels used up in achieving high
> temperatures cost more today and
> will only cost more in the future. Electricity, on
> the other hand , soon
> will be less expensive and, with the advancing
> technological developments in
> solar cells, will be clean and renewable.
> Many potters don't have access to ,or facilities
> for, a gas kiln. Electric
> reduction offers a
> way to get copper reds in in a small electric kiln,
> in a home studio.I hope
> to try ER (electric reduction) in my tiny test kiln
> to see if I can get the
> same bright copper reds I now get from my 11 cu ft
> kiln.
> As far as elements go , I have had conversations
> with several ceramic
> engineers about the reasons for failures , and I
> now believe that it
> isn't the reduction that causes the failure in
> elements. One said that it
> was more likely caused by stressing the elements
> going to cone ten over
> and over. As far as my experiments go, I will find
> out how long the
> elements last , in time. All is for the sake of
> research and the
> thrill of pushing the edge of the envelope a
> little.
>
>
> David
> Turner
> On Dec 11, 2007 9:08 AM, Charlie Hightower
>
> wrote:
>
> > I don't know about your TOP SECRET design, but the
> > best way to build an electric reduction kiln is to
> use
> > silicon carbide rod type elements. They are immune
> to
> > reduction. Also, they last MUCH longer as well as
> can
> > fire much hotter then cone 10 (if you choose).
> > However, building such a kiln would be very
> pricey. If
> > someone could put a line of 5-8 cubic foot top
> loaders
> > using Silicon Carbide rods for under $5000 then
> they
> > would stand to do very well. I did some electric
> > reduction utilizing ITC products with mixed
> success.
> > Gave it up after building a small gas kiln, but
> would
> > surely go back if I never had to change elements.
> > Firing to cone 6-10 in such a kiln I doubt I ever
> > would. As far as pollution is concerned my
> electric
> > kiln probably pollutes more then my natural gas
> job
> > considering the coal burned to power it. Take care
> and
> > good luck. Keep us posted please.
> > --- David Turner wrote:
> >
> > > Hi again ...it's been 24 hrs and I got loads of
> > > e-mails...The only problem
> > > is that I am a slow typist so a quick response
> to
> > > everyone will take awhile.
> > >
> > > The process I am working with is TOP SECRET and
> my
> > > lawyer advised me not to
> > > talk in too much detail just yet. (I was just
> > > kidding about the TOP SECRET
> > > stuff.)
> > > The main achievement is the reduction of
> > > carbonaceous material required to
> > > get a perfectly balanced reducing atmosphere.You
> > > might say it is a
> > > convenient solution to potter pollution.The best
> > > part of the process for
> > > myself is the increased intimacy with the
> element of
> > > fire. This isn't
> > > Ronco's "set it and forget it"
> > > easy bake oven kind of thing.It's hands on, but
> very
> > > simple and I guess I
> > > just find it totally exciting and lots of fun,
> and I
> > > hope to share it soon.
> > > Thanks for all of the great e-mails.
> > > Does anyone know Al Gore's e-mail address?
> > >
> David
> > > T.
> > >
> > >
> >
>
______________________________________________________________________________
> >
> > > 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
> > >
> >
> >
> >
>
______________________________________________________________________________
> > 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
> >
>
>
______________________________________________________________________________
> 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
>

Earth Nouveau on sun 16 dec 07


Hey Earl.....
There are few sure things in testing out new stuff...except... maybe
discovering something new that may be an advance in the way we do things. I
plan to use my current kiln to bisque and glaze in and I look forward to
the day that the elements go pop.Then I will know, for sure that all the
stories about reduction being tough on elements is true. Element failures
occur for many reasons and if anyone has tried to do electric reduction and
had elements pop I wouldn't rush to judgment as to what the cause was. I
do have ITC on the walls and elements, applied by the factory and I have a
feeling that this might extend their life. I have never seen conclusive
scientific evidence or results of any tests conducted by anyone about how
long they last in a reduction atmosphere or for that matter any tests to
determine how much firing to cone ten shortens the life of elements
either. On the other hand , if I get years of firings out of it, then I
will have been able to break through a barrier that a lot of us out here
are currently up against .The limitations of glazes one can get might only
be limited by imagination and not because you don't own or have access to
a gas ,oil,or wood fired kiln,or the space to have one.
So until they pop, I will be taken my chances and trying to learn some
new dances and take a road less traveled
So far it's a been a great one. I hope to some day meet many more potters
on it.
thank you for the
feed back

David
Turner

On Dec 10, 2007 10:37 PM, Earl Brunner wrote:

> Don't care if it's "secret" or proprietary, if you can't answer the
> questions regarding solving the problems with electric elements in reduction
> having a significantly shorter life, then you will have limited success
> selling them.
>
>
> ----- Original Message ----
> From: David Turner
> To: CLAYART@LSV.CERAMICS.ORG
> Sent: Monday, December 10, 2007 6:38:05 PM
> Subject: ER(electric reduction)
>
> Hi again ...it's been 24 hrs and I got loads of e-mails...The only problem
> is that I am a slow typist so a quick response to everyone will take
> awhile.
>
> The process I am working with is TOP SECRET and my lawyer advised me not
> to
> talk in too much detail just yet. (I was just kidding about the TOP SECRET
> stuff.)
> The main achievement is the reduction of carbonaceous material required
> to
> get a perfectly balanced reducing atmosphere.You might say it is a
> convenient solution to potter pollution.The best part of the process for
> myself is the increased intimacy with the element of fire. This isn't
> Ronco's "set it and forget it"
> easy bake oven kind of thing.It's hands on, but very simple and I guess I
> just find it totally exciting and lots of fun, and I hope to share it
> soon.
> Thanks for all of the great e-mails.
> Does anyone know Al Gore's e-mail address?
> David T.
>
>
> ______________________________________________________________________________
> 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
>
>
> ______________________________________________________________________________
> 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
>

Earl Brunner on mon 17 dec 07


Not sure what you mean by "pop". My understanding may be a little simplistic, it is that in an electric kiln, the elements oxidize on the surface and that the oxidation layer then slows the oxidation underneath it. Reduction removes some of the oxidation layer each time you do it. So over time the elements get thinner and thinner until they fail. The rate of failure is supposed to be more rapid than if you don't do reduction in the kiln.

There are other factors at work though. "Most" people will attempt reduction probably at cone 10, just because there isn't a lot out there about reduction at cone 6, or at least there hasn't been. Cone 10 significantly reduces the life of elements all by itself. I have seen kilns that are only fired to around 1800 degrees get many more firings out of the elements than those fired to higher temps. Cone 6 firings shorten the life of the elements, and cone 10 shorter still. ITC is supposed to form a protective layer over the elements that protects or slows the oxidation. The potential problem with it would be that the coating would only be as good as it's weakest area. One little crack in the coating could reduce it's effectiveness.

I have a friend here that fires all of her sculptural porcelain stuff in cone 10 oxidation http://www.windancerstudio.com/. She does long soaks at the high end. This should be murder on her elements. She says not. A few years ago I helped her replace the elements in her kiln, and she does it herself now. The elements we put in were ITC coated (and I think "heavy duty). She feels that the ITC coating has extended the life of the elements. It's been a couple of years and I think only one element in the door failed and that was early on, so it may have had a problem.

To illustrate an idea though, I would compare it to mixing glazes. Some of the 5 gallon batches of glaze I mix up cost 3-4 dollars a gallon. Some cost 10-20 or even higher per gallon, depending on what's in them. So I have a five gallon bucket of glaze that costs 14-20 dollars and I have a bucket that costs 50 to 100 dollars. In the greater scheme of things, I can pay for that 100 dollar bucket with one pot. So if the glaze is good, and I can't get the affect with anything else, why would I not make it. I think what we are talking about is the same. If you can only fire electric and you have to replace your elements every 50 firings instead of every 100 firings, then the question is, does that affect the price of your work significantly? One or two pots can cover the cost of the elements.

Earl Brunner
Las Vegas, NV



----- Original Message ----
From: Earth Nouveau
To: CLAYART@LSV.CERAMICS.ORG
Sent: Sunday, December 16, 2007 2:22:04 PM
Subject: Re: ER(electric reduction)

Hey Earl.....
There are few sure things in testing out new stuff...except... maybe
discovering something new that may be an advance in the way we do things. I
plan to use my current kiln to bisque and glaze in and I look forward to
the day that the elements go pop.Then I will know, for sure that all the
stories about reduction being tough on elements is true. Element failures
occur for many reasons and if anyone has tried to do electric reduction and
had elements pop I wouldn't rush to judgment as to what the cause was. I
do have ITC on the walls and elements, applied by the factory and I have a
feeling that this might extend their life. I have never seen conclusive
scientific evidence or results of any tests conducted by anyone about how
long they last in a reduction atmosphere or for that matter any tests to
determine how much firing to cone ten shortens the life of elements
either. On the other hand , if I get years of firings out of it, then I
will have been able to break through a barrier that a lot of us out here
are currently up against .The limitations of glazes one can get might only
be limited by imagination and not because you don't own or have access to
a gas ,oil,or wood fired kiln,or the space to have one.
So until they pop, I will be taken my chances and trying to learn some
new dances and take a road less traveled
So far it's a been a great one. I hope to some day meet many more potters
on it.
thank you for the
feed back

David
Turner

Charlie Hightower on mon 17 dec 07


When I coat my elements with ITC for metals I mix it
to a THIN consistency and pour into a wallpaper
stripping tray. Looks like tea. I then can run them
through once, hang outside with cloth spins, then blow
drips off with an air compressor. Elements should look
tinted but still visible through the coat. I clean the
pigtails well where they will contact the connectors.
Install and give the whole kiln a fresh coat of ITC
100. Again, THIN. Less awkward with two people.
--- Earl Brunner wrote:

> Not sure what you mean by "pop". My understanding
> may be a little simplistic, it is that in an
> electric kiln, the elements oxidize on the surface
> and that the oxidation layer then slows the
> oxidation underneath it. Reduction removes some of
> the oxidation layer each time you do it. So over
> time the elements get thinner and thinner until they
> fail. The rate of failure is supposed to be more
> rapid than if you don't do reduction in the kiln.
>
> There are other factors at work though. "Most"
> people will attempt reduction probably at cone 10,
> just because there isn't a lot out there about
> reduction at cone 6, or at least there hasn't been.
> Cone 10 significantly reduces the life of elements
> all by itself. I have seen kilns that are only
> fired to around 1800 degrees get many more firings
> out of the elements than those fired to higher
> temps. Cone 6 firings shorten the life of the
> elements, and cone 10 shorter still. ITC is
> supposed to form a protective layer over the
> elements that protects or slows the oxidation. The
> potential problem with it would be that the coating
> would only be as good as it's weakest area. One
> little crack in the coating could reduce it's
> effectiveness.
>
> I have a friend here that fires all of her
> sculptural porcelain stuff in cone 10 oxidation
> http://www.windancerstudio.com/. She does long
> soaks at the high end. This should be murder on her
> elements. She says not. A few years ago I helped
> her replace the elements in her kiln, and she does
> it herself now. The elements we put in were ITC
> coated (and I think "heavy duty). She feels that
> the ITC coating has extended the life of the
> elements. It's been a couple of years and I think
> only one element in the door failed and that was
> early on, so it may have had a problem.
>
> To illustrate an idea though, I would compare it to
> mixing glazes. Some of the 5 gallon batches of
> glaze I mix up cost 3-4 dollars a gallon. Some cost
> 10-20 or even higher per gallon, depending on what's
> in them. So I have a five gallon bucket of glaze
> that costs 14-20 dollars and I have a bucket that
> costs 50 to 100 dollars. In the greater scheme of
> things, I can pay for that 100 dollar bucket with
> one pot. So if the glaze is good, and I can't get
> the affect with anything else, why would I not make
> it. I think what we are talking about is the same.
> If you can only fire electric and you have to
> replace your elements every 50 firings instead of
> every 100 firings, then the question is, does that
> affect the price of your work significantly? One or
> two pots can cover the cost of the elements.
>
> Earl Brunner
> Las Vegas, NV
>
>
>
> ----- Original Message ----
> From: Earth Nouveau
> To: CLAYART@LSV.CERAMICS.ORG
> Sent: Sunday, December 16, 2007 2:22:04 PM
> Subject: Re: ER(electric reduction)
>
> Hey Earl.....
> There are few sure things in testing out new
> stuff...except... maybe
> discovering something new that may be an advance in
> the way we do things. I
> plan to use my current kiln to bisque and glaze in
> and I look forward to
> the day that the elements go pop.Then I will know,
> for sure that all the
> stories about reduction being tough on elements is
> true. Element failures
> occur for many reasons and if anyone has tried to do
> electric reduction and
> had elements pop I wouldn't rush to judgment as to
> what the cause was. I
> do have ITC on the walls and elements, applied by
> the factory and I have a
> feeling that this might extend their life. I have
> never seen conclusive
> scientific evidence or results of any tests
> conducted by anyone about how
> long they last in a reduction atmosphere or for that
> matter any tests to
> determine how much firing to cone ten shortens the
> life of elements
> either. On the other hand , if I get years of
> firings out of it, then I
> will have been able to break through a barrier that
> a lot of us out here
> are currently up against .The limitations of glazes
> one can get might only
> be limited by imagination and not because you
> don't own or have access to
> a gas ,oil,or wood fired kiln,or the space to have
> one.
> So until they pop, I will be taken my chances
> and trying to learn some
> new dances and take a road less traveled
> So far it's a been a great one. I hope to some
> day meet many more potters
> on it.
>
> thank you for the
> feed back
>
>
> David
> Turner
>
>
______________________________________________________________________________
> 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
>

Ivor and Olive Lewis on tue 18 dec 07


Dear David Turner,
The process you are describing sounds fascinating but it seems to be =
long on rhetoric but short on science and technology.
My own experience of heat treatment in a reducing atmosphere within an =
electric kiln is that there have to be complex operating protocols which =
must be rigorously implemented to prevent potential catastrophes.
Perhaps degradation of heating elements made from metals under the =
influence of alternating atmospheric conditions is due to progressive =
oxidation along grain boundaries within the structure of the wire. This =
would increase the pathway distance with a progressive diminution of =
effective cross section. Presumably increasing resistance forces the =
temperature of the conductor to rise until it melts.
Best regards,
Ivor Lewis.
Redhill,
South Australia.

Charlie Hightower on tue 18 dec 07


Lee,
A microwave kiln? Now thats an idea. They are doing
this you say? I knew about all the electric reduction
going on over there. I'm assuming the heavier elements
degrade much slower in reduction but still degrade
unless made from something I don't know of? The only
elements I know of that are immune to reduction are
Silicon Carbide rods. I don't know about platinum but
their price means I never will need to care.
--- Lee Love wrote:

> Hi David,
>
> How clean your electricity is, depends on
> its source.
> Nuclear is the dirtiest fuel, solar very clean. We
> assume electricity
> is clean because we don't see the pollution because
> the coal is burnt
> out of our sight. The majority of carbon put in the
> air by China's
> increasing demands for power comes from coal. It
> has huge reserves of
> coal.
> ]
> The most practical ecological fuel is
> wood, especially if
> you keep your own woodlot. 2/3rds of the carbon
> trapped by trees
> stays in the woods in the form of roots and also
> leaves and bark that
> enrich the soil. That being said....
>
> Potters regularly do reduction in
> electric firing here
> in Japan, with little LPG burners, boxes under the
> kiln for reduction
> materials, or by using charcoal saggers inside the
> kiln. They get
> very nice results. But their electric kilns use
> heavier elements
> that don't degrade when exposed to the reduction
> atmosphere. Their
> kilns are better insulated too and cost more than
> our kilns in the
> States. Just look in the archives and you will
> find many posting
> about this. You can also find mention of the
> microwave/electric
> kilns that are common here in Japan. These are
> very efficient! All
> kinds of fuel cost more here.
>
> If potters are willing to pay for
> reduction electric kilns
> and create a demand for them, the kiln companies
> will make them. I
> am guessing fuel prices will have to go higher
> before folks start
> demanding them.
>
>
> --
> Lee in Mashiko, Japan
> http://groups.google.com/group/ClayCraft
>
> "Men are born ignorant, not stupid. They are made
> stupid by
> education." -- Bertrand Russell
>
>
______________________________________________________________________________
> 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
>

John Sankey on tue 18 dec 07


"Nuclear is the dirtiest fuel, solar very clean."

As one who has studied the life cycle carbon costs of electricity
a fair bit, I can't let this go by. It's the other way around
when you add up all the carbon costs of building, maintaining,
and decommissioning the system as well as the output.

See http://sankey.ws/carbonbudget for some numbers.

--
Include 'Byrd' in the subject line of your reply
to get through my spam filter.

Lee Love on tue 18 dec 07


On 12/18/07, Charlie Hightower wrote:

> A microwave kiln? Now thats an idea. They are doing
> this you say?

Yes, they heat very quickly, but cool at a normal rate.

> unless made from something I don't know of? The only
> elements I know of that are immune to reduction are
> Silicon Carbide rods.

They are not wire but more like rods. Like the elements in an
electric oven. I have photos on the web somewhere. Found it on
Google:

http://claycraft.blogspot.com/2005/11/heavy-elements-in-japanese-electric.html

They come from the factory all ready to go, including a little
bunsen type gas burner, see below:

http://claycraft.blogspot.com/search?q=burner

But most of the potters I talked to at the Pottery Festival
just put a charcoal sagger in the bottom of their heavy element kilns
and do reduction that way.


--
Lee in Mashiko, Japan
http://groups.google.com/group/ClayCraft

"Men are born ignorant, not stupid. They are made stupid by
education." -- Bertrand Russell

Lee Love on tue 18 dec 07


Hi David,

How clean your electricity is, depends on its source.
Nuclear is the dirtiest fuel, solar very clean. We assume electricity
is clean because we don't see the pollution because the coal is burnt
out of our sight. The majority of carbon put in the air by China's
increasing demands for power comes from coal. It has huge reserves of
coal.
]
The most practical ecological fuel is wood, especially if
you keep your own woodlot. 2/3rds of the carbon trapped by trees
stays in the woods in the form of roots and also leaves and bark that
enrich the soil. That being said....

Potters regularly do reduction in electric firing here
in Japan, with little LPG burners, boxes under the kiln for reduction
materials, or by using charcoal saggers inside the kiln. They get
very nice results. But their electric kilns use heavier elements
that don't degrade when exposed to the reduction atmosphere. Their
kilns are better insulated too and cost more than our kilns in the
States. Just look in the archives and you will find many posting
about this. You can also find mention of the microwave/electric
kilns that are common here in Japan. These are very efficient! All
kinds of fuel cost more here.

If potters are willing to pay for reduction electric kilns
and create a demand for them, the kiln companies will make them. I
am guessing fuel prices will have to go higher before folks start
demanding them.


--
Lee in Mashiko, Japan
http://groups.google.com/group/ClayCraft

"Men are born ignorant, not stupid. They are made stupid by
education." -- Bertrand Russell

Chaeli Sullivan on tue 18 dec 07


Lee
Following your second link -- if we rigged a propane burner and attached it to the peep-hole of the electric kiln -- we could achieve reduction !!!
Awesome info.
Am so tired right this moment ( only 4 hours sleep followed by a full day of Christmas shopping) i can hardly keep my eyes open but i just know after seeing your photos of this that tomorrow i'll have thousands of ideas on how to accomplish this with my kiln.
Thank you very much!
Chae
http://www.claygallimaufry.blogspot.com



Lee Love wrote:
On 12/18/07, Charlie Hightower wrote:

> A microwave kiln? Now thats an idea. They are doing
> this you say?

Yes, they heat very quickly, but cool at a normal rate.

> unless made from something I don't know of? The only
> elements I know of that are immune to reduction are
> Silicon Carbide rods.

They are not wire but more like rods. Like the elements in an
electric oven. I have photos on the web somewhere. Found it on
Google:

http://claycraft.blogspot.com/2005/11/heavy-elements-in-japanese-electric.html

They come from the factory all ready to go, including a little
bunsen type gas burner, see below:

http://claycraft.blogspot.com/search?q=burner

But most of the potters I talked to at the Pottery Festival
just put a charcoal sagger in the bottom of their heavy element kilns
and do reduction that way.


--
Lee in Mashiko, Japan
http://groups.google.com/group/ClayCraft

"Men are born ignorant, not stupid. They are made stupid by
education." -- Bertrand Russell

______________________________________________________________________________
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



---------------------------------
Never miss a thing. Make Yahoo your homepage.

Ivor and Olive Lewis on wed 19 dec 07


Dear Charlie Hightower,

As I recall, Platinum suffers from Hydrogen Embrittlement but does not =
oxidise. Molybdenum does not suffer from Hydrogen embrittlement.

Thermal cycling induces grain boundary cracks and Pt/PtRh couples =
eventually fail. But because Molybdenum oxidises readily it has to be =
contained in a hydrogen atmosphere. Furnaces wound with Moly must be =
filled with Hydrogen before they are heated. That atmosphere has to be =
maintained for life of the kiln.

Best regards,

Ivor Lewis.
Redhill,
South Australia.