D. McDysan on mon 5 oct 98
The response to the question about reduction firing in an electric kiln
was that the fumes would be toxic and the elements would be damaged. I'd
like to know if the fumes would be handled safely with a vent and how
many firings would it take for the elements to go kaput?
I 've been considering trying this in my new electric kiln but I don't
want to replace the elements for many years because it is a rectagular
front loader. I do, however have an old round paragon that is real close
to becoming a raku kiln so maybe I could experiment in that first before
it dies.
Does anyone have information about this? What do I use to create the
reduction, when and for how long? What clays and glazes work best?
If the gurus say forget it, I will heed the advice but ever since I saw
Beatrice Wood put those sticks in her kiln (on the video - Mama of Dada)
I've been real curious.
Debbie McDysan
dmcdysan@onramp.net
http://rampages.onramp.net/~dmcdysan
Donn Buchfinck on tue 6 oct 98
I have heard that people put moth balls it thier kiln
this could be an urban legend
what I would do to reduce my kiln it I would thrown a heavy saggar that has a
tight fitting lid
if the kiln has a downdraft vent on it this might help if not well try it
anyway
fill it up with charcole briquets and put the lid on and put it on the top
shelf of your kiln
when the kiln gets hot lift the lid, "make sure you are waering gloves and a
face grinding shield, maybe get someone to help you do this part" and reach in
with a pair of raku tongs and remove the lid to the saggar. this might reduce
the kiln.
the other way is to put something that will burn, really I have heard of
people using moth balls, but I have also heard of people salt firing with
uranium Oxide
I do not realy think that reducing an electric kiln will hurt the elements,
Ok I'm not an element person but what I thought made the elements go bad was
them oxidising.
just remember that you might be on to something, and do not let anyone tell
you an idea is stupid, just make sure when you do this the kiln is outside
and well ventalated.
thanks
Donn "try anything once" Buchfinck
Louis Katz on wed 7 oct 98
Moth balls are not Urban Legend.
We used to use them in attempts to get lustered surfaces in the late seventies.
Probably a pretty foolish thing to use.
Louis Katz on wed 7 oct 98
Sorry if the last post got through,
I have reduced kilns with moth balls, but have gotten better results from gas.
Make sure your kiln is hot enough to combust the gas though or you could ennd up
exploding your kiln. We (I , for a friend) once moth balled a kiln below red
heat, as I was walking away I heard a "poof" and the spy plugs had popped out.
Seems It too a while for sufficient gas to collect around something hot enough t
combust it.
A few years ago some at NCECA gave a talk and described reduce kilns with a
commercially available mixture of 5% hydrogen in Nitrogen.
The chemistry behind the problems with reducing electric kilns ( as I have heard
it) is that it also reduces the oxide coating on the elements which serve as a
protective coating. Once exposed the elements can alloy themselves with other
compounds they come into contact with, carbon, iron etc..
I have not done enough reduction in electric kilns to tell you how hard it is on
elelments, but I do know that burning off organic matter is hard on the metal
cases and kiln ventilation equipment.
Louis
Vince Pitelka on wed 7 oct 98
>I have heard that people put moth balls it thier kiln
>this could be an urban legend
>what I would do to reduce my kiln it I would thrown a heavy saggar that has a
>tight fitting lid
Donn's suggestion reminds me of a very clever idea I heard of, but I do not
know of anyone who has tried it. If you want to reduce in an electric kiln,
why not fabricate a large sagger inside the kiln, using a very refractory
clay to make the sagger reuseable, and give it a tight-fitting bottom and
top. Enlarge the spy holes at the appropriate locations in your kiln, and
fabricate several refractory tubes which fit from the spyhole to a
corresponding hole in the sagger, one near the bottom and one near the top
of the sagger. When you wish to do reduction, insert your reduction
materials through bottom tube, and draw off the excess smoke and fumes
through the top tube, using some sort of damper to restrict the flow at the
top tube in order to maintain the reducing atmosphere inside the sagger.
You might consider using a woven fiber gasket in the sagger joints to make
it even tighter. A small amount of reduction gases will end up coming in
contact with the elements, but it will be very minimal as compared to doing
electric reduction without a sagger.
Someone try this and let us know how it works.
- Vince
Vince Pitelka - vpitelka@DeKalb.net
Home 615/597-5376, work 615/597-6801, fax 615/597-6803
Appalachian Center for Crafts
Tennessee Technological University
1560 Craft Center Drive, Smithville TN 37166
Tom Buck on wed 7 oct 98
Mr Buchfinck:
1) Mothballs used to be pure hydrocarbon, naphthalene, but not
today; now, MBs are usually dichlorobenzene, a rather hyper dangerous
chemical if breathed in to any extent.
2) Kanthal element wire, the usual alloy used, contains iron,
aluminum, other metals. The aluminum oxidizes and forms an Al2O3 coating
on the wire's surface, and this oxide coating is fairly durable and halts
further degradation. However, the Al2O3 will be attacked by carbon/carbon
monoxide, halogens (fluorine, chlorine, etc.), and halides. So for long
life of elements one should attempt to avoid these materials.
However, your idea of a saggar with a tight lid is probably the
best approach to obtaining reducing conditions in an electric kiln. The
trick will be to find just the right amount of coal, briquet, wood, etc.
to achieve a reduced glaze on the pot(s) in the saggar, and not too much
to cause the reducing agent to fill the whole inside of the kiln.
Tom Buck ) tel: 905-389-2339 & snailmail: 373 East
43rd St. Hamilton ON L8T 3E1 Canada (westend Lake Ontario, province of
Ontario, Canada).
P.G.Hamer on wed 7 oct 98
Donn Buchfinck wrote:
>
> I do not realy think that reducing an electric kiln will hurt the elements,
> Ok I'm not an element person but what I thought made the elements go bad was
> them oxidising.
A reasonable thought, but wrong. Most elements (like aluminium and
stainless steel) rely on a surface layer of oxide for protection.
Peter
Barney Adams on thu 8 oct 98
I thought (maybe incorrectly) that I had read an article that
once exposed to a reduction atmosphere that further oxidized
firings help restore damaged elements. Is this true? I have gotten
some reduction from my electric by inserting small twigs into the
bottom spyhole. I have always done several oxidation firings inbetween
the reductions and I dont try reduction very often. I'd hate to give up
the nice change to some of my glazes (a nice celedon for one).
but I dont want to change elements too soon.
Barney
>
> ----------------------------Original message----------------------------
> Mr Buchfinck:
> 1) Mothballs used to be pure hydrocarbon, naphthalene, but not
> today; now, MBs are usually dichlorobenzene, a rather hyper dangerous
> chemical if breathed in to any extent.
> 2) Kanthal element wire, the usual alloy used, contains iron,
> aluminum, other metals. The aluminum oxidizes and forms an Al2O3 coating
> on the wire's surface, and this oxide coating is fairly durable and halts
> further degradation. However, the Al2O3 will be attacked by carbon/carbon
> monoxide, halogens (fluorine, chlorine, etc.), and halides. So for long
> life of elements one should attempt to avoid these materials.
> However, your idea of a saggar with a tight lid is probably the
> best approach to obtaining reducing conditions in an electric kiln. The
> trick will be to find just the right amount of coal, briquet, wood, etc.
> to achieve a reduced glaze on the pot(s) in the saggar, and not too much
> to cause the reducing agent to fill the whole inside of the kiln.
>
> Tom Buck ) tel: 905-389-2339 & snailmail: 373 East
> 43rd St. Hamilton ON L8T 3E1 Canada (westend Lake Ontario, province of
> Ontario, Canada).
>
Cameron Harman on thu 8 oct 98
Ther have been a lot of well reasoned comments on this issue.
In addition to Vince's comments, it might help you to know that
the idea of using a large sealed refractory container is well
thought of. Even in gas fired kilns where a carbonaceous product
if being fired, this idea allows for continuous reduction (or lack
of oxygen). The containers are continually reused. Materials
containing carbon, as you know, will burn at very low
temperatures, so they must be sealed from the beginning of the
fire.
This same idea is used by some makers of high lead glazed ware as
a means of containing the lead fumes during firing. It is quite
successful and saves the kiln lining as well as reducing lead
emmisions. Many of those people have now converted to non lead
glazes so no longer need to fire this way.
On the other hand, some commerciall people fire reducing in
electric kilns by introducing various gasses. The reduced life of
the elements is simply part of the cost of reduction firing. The
Kanthal elements will hold up for a reasonable period of time, but
much less than in oxidizing firing.
I do not like the idea of moth balls, however, as I have seen
large kilns using similar compounds blow up. It is possible to
have a reducing atmosphere in the kiln, then, for some reason,
after the kiln is at red heat, it is expposed to air. It will
explode immediatly with great force. You could kill yourself,
either from the explosion or as others have said, from the toxic
fumes. It is a good thought, but like a lot of things we used to
do, we have learned safer ways.
Cameron
--
**********************************************************
Cameron G. Harman, Jr. 215-245-4040 fax 215-638-1812
e-mail kilns@kilnman.com
Ceramic Services, Inc 1060 Park Ave. Bensalem, PA 19020
get your free ezine: http://www.kilnman.com/ezine/ezine.html
THE place for total kiln and drier support
**********************************************************
Cindy on thu 8 oct 98
Just a short comment . . .
Why not let your electric kiln fire the best electric-fired pots it can?
Electric kilns do all sorts of wonderful things which are difficult, if not
impossible to accomplish in a fuel-burning kiln. I would like to have a
fuel kiln, and will have one when things come together, but in the mean
time, I choose to explore the limitless possibilities inherent in oxidation
firing. There's plenty here for me yet to learn.
I have long, straight hair. For years, I tried to get it to curl. Silly
girl--I have plenty of friends with curly hair who try to get their tresses
to lay straight. My hair is medium blonde--a real pretty golden color, but
I've longed for anything from black to red (and never quite had the nerve
to do it, thank God). I'm tall; I want to be shorter (not much I can do
about that). Why is it we always want what we don't have? An electric kiln
is a wonderful tool. Why not just appreciate it for what it is?
Cindy Strnad
Earthen Vessels
Custer, SD
USA http://blackhills-info.com/a/cindys/menu.htm
Don & Isao Morrill on thu 8 oct 98
At 08:58 10/7/98 EDT, you wrote:
>----------------------------Original message----------------------------
>>I have heard that people put moth balls it thier kiln
>>this could be an urban legend
>>what I would do to reduce my kiln it I would thrown a heavy saggar that
has a
>>tight fitting lid
>
>Donn's suggestion reminds me of a very clever idea I heard of, but I do not
>know of anyone who has tried it. If you want to reduce in an electric kiln,
>why not fabricate a large sagger inside the kiln, using a very refractory
>clay to make the sagger reuseable, and give it a tight-fitting bottom and
>top. Enlarge the spy holes at the appropriate locations in your kiln, and
>fabricate several refractory tubes which fit from the spyhole to a
>corresponding hole in the sagger, one near the bottom and one near the top
>of the sagger. When you wish to do reduction, insert your reduction
>materials through bottom tube, and draw off the excess smoke and fumes
>through the top tube, using some sort of damper to restrict the flow at the
>top tube in order to maintain the reducing atmosphere inside the sagger.
>You might consider using a woven fiber gasket in the sagger joints to make
>it even tighter. A small amount of reduction gases will end up coming in
>contact with the elements, but it will be very minimal as compared to doing
>electric reduction without a sagger.
>
>Someone try this and let us know how it works.
>- Vince
> I trust you mean the saggar and not the mothballs. I had heard of the
mothballs several times but,considering the chemistry of mothballs,I
certainly would not attempt using them for reduction. Phillip White, a
former student of mine bought me out in Marblehead,Mass and started a small
company manufacturing the Production Reduction Factory. He used somewhat
large elements and introduced a small box to hold charcoal,a the bottom of
the kiln which could be withdrawn or admitted at will. Don't know what ever
happened to this idea. f the object is to reduce oxygen,why not introduce
an inert gas...Nitrogen... as is done industrially in various processes.
The first time I read of reduction in electric kilns may have been in
Leach's ""Potters Book" or some such....where it was pointed out that using
various materials in electric kilns for reduction,would result in an
estimated 10% additional wear of the elements over time. If this was meant
to mean' over the normal estimated lifetime of the elements then, one could
certainly tolerate this over the large number of firings one usually
gets,arring element breakage. Don Morrill
>
>Vince Pitelka - vpitelka@DeKalb.net
>Home 615/597-5376, work 615/597-6801, fax 615/597-6803
>Appalachian Center for Crafts
>Tennessee Technological University
>1560 Craft Center Drive, Smithville TN 37166
>
>
Vince Pitelka on thu 8 oct 98
At 09:09 AM 10/7/98 -0400, you wrote:
>----------------------------Original message----------------------------
>Donn Buchfinck wrote:
>>
>> I do not realy think that reducing an electric kiln will hurt the elements,
>> Ok I'm not an element person but what I thought made the elements go bad
was them oxidising.
Peter Hammer wrote:
>
>A reasonable thought, but wrong. Most elements (like aluminium and
>stainless steel) rely on a surface layer of oxide for protection.
Peter -
I'm not sure you can technically say this is wrong. It is true that Kanthal
elements build up a layer of oxidation which protects them, but that happens
only if they stop oxidizing. If you erode that layer of oxidation, they
continue to oxidize deeper into the core metal, and eventually they fail.
Is Chris from Euclid's listening, and if so, am I correct in this assumption?
- Vince
Vince Pitelka - vpitelka@DeKalb.net
Home 615/597-5376, work 615/597-6801, fax 615/597-6803
Appalachian Center for Crafts
Tennessee Technological University
1560 Craft Center Drive, Smithville TN 37166
Fred Paget on fri 9 oct 98
Tom:
You are sure right about the composition of modern mothballs. Don't use them.
I understand that some potters are using salad oil dripped into a kiln to
get reduction in electric kilns. The same problem with elements exists but
if you do an oxidation firing after the reduction one and accept the short
element life you can do some firing. Then replace the elements and coat the
new ones with that ITC213 while they are out of the kiln.
There is a man who builds kilns for industry, mainly, near here
(Contemporary Kilns) that I visited to buy a high tech platinum
thermocouple from.
He has a model in his office/showroom of a type of electric kiln he builds
for glass annealing. It is a cute little working model of the bigger kilns
and it has globar elements in it. For those younger potters out there
globar rods are made of silicon carbide and are not damaged by reducing
atmospheres.
These are a new configuration of globar; that is a tube that has been
spiral cut to make a helix. The result is a globar that will run on 240
volts line voltage unlike the old globar kilns sold to potters in the 50's
and 60's by Alpine. They required a very low voltage and huge current which
meant a transformer weighing a couple of hundred pounds and some copper bus
bar to carry the current to the elements. Truly an expensive thing in this
day and age. There is a picture of one of these in Sanders book "Glazes for
Special Effects".
These new globars are not cheap either but he said he could build me a 12
cubic foot electric kiln using them for under 10,000 dollars and you can do
reduction in them without hurting the elements. Too bad I don't have an
extra $10K to buy one! Also you can reach about 3000 deg. F with globar.
Put a little smokestack on that and a little firebox for charcoal and you
have a reduction electric kiln. Somewhere I read that there were a couple
of these in Japan.
>----------------------------Original message----------------------------
>Mr Buchfinck:
> 1) Mothballs used to be pure hydrocarbon, naphthalene, but not
>today; now, MBs are usually dichlorobenzene, a rather hyper dangerous
>chemical if breathed in to any extent.
> 2) Kanthal element wire, the usual alloy used, contains iron,
>aluminum, other metals. The aluminum oxidizes and forms an Al2O3 coating
>on the wire's surface, and this oxide coating is fairly durable and halts
>further degradation. However, the Al2O3 will be attacked by carbon/carbon
>monoxide, halogens (fluorine, chlorine, etc.), and halides. So for long
>life of elements one should attempt to avoid these materials.
> However, your idea of a saggar with a tight lid is probably the
>best approach to obtaining reducing conditions in an electric kiln. The
>trick will be to find just the right amount of coal, briquet, wood, etc.
>to achieve a reduced glaze on the pot(s) in the saggar, and not too much
>to cause the reducing agent to fill the whole inside of the kiln.
>
> Tom Buck
From Fred Paget, in marvelous Marin County, California, USA
Gavin Stairs on fri 9 oct 98
At 09:23 AM 10/8/98 EDT, you wrote:
>----------------------------Original message----------------------------
>I thought (maybe incorrectly) that I had read an article that
>once exposed to a reduction atmosphere that further oxidized
>firings help restore damaged elements. Is this true? I have gotten
>some reduction from my electric by inserting small twigs into the
>bottom spyhole. I have always done several oxidation firings inbetween
>the reductions and I dont try reduction very often. I'd hate to give up
>the nice change to some of my glazes (a nice celedon for one).
>but I dont want to change elements too soon.
The people from Euclid's or somewhere else may have a more authoritative
answer to this. My answer is that any disruption to the oxide film is
likely to shorten the life of the elements. This is rather like the life
of a stainless steel cooking pot. If you never overcook or carbonize the
bottom, or cook strong alkalis, it is likely never to fail. However, if
you once get a pit going, nothing you may do is likely to arrest the
tendency to corrode and eventually fail. So you get a hole in the pot.
The equivalent with an element is that the element gets smaller at one
place, that place gets hotter and hotter, until it melts or oxidizes to
failure.
The other factor is the temperature you operate at. If you are only low
firing (say, cone6 or below), your elements are likely to last a long time
no matter what you do. It is only up near cone 10 that element life become
a big concern. The element temperature is hotter than the kiln
temperature, and elements decay by sublimation of the less refractory parts
of the metal, like Fe and Cr, leaving more and more Al. This makes the
metal brittle, and eventually leads to failure, usually by runaway
(catastrophic) local heating. This process increases in rate exponentially
with temperature, so below about cone20 or so, you element life is
indefinite. Above that, they will fail eventually: it's only a matter of
when.
It may well be that if you only fire at low temperatures, elements of
FeCrAl may last quite a long time in reduction, and longer with regular
re-oxidation. I don't know the full answer, and I would like to do some
experiments to find out, but I won't have results for some time.
I urge you to read the notes that come with your kiln (if any) concerning
expected element life, or go to
and read the portion about
element life and conditioning. You can also look about at
. If you intend to reduction fire, you might be
interested in using an element overcoat, like the one sold by ITC.
Gavin
Bonnie Staffel on fri 9 oct 98
----------------------------Original message----------------------------
> Just a short comment . . .
>
> Why not let your electric kiln fire the best electric-fired pots it can?
> Electric kilns do all sorts of wonderful things which are difficult, if not
> impossible to accomplish in a fuel-burning kiln. I would like to have a
> fuel kiln, and will have one when things come together, but in the mean
> time, I choose to explore the limitless possibilities inherent in oxidation
> firing. There's plenty here for me yet to learn.
>
> I have long, straight hair. For years, I tried to get it to curl. Silly
> girl--I have plenty of friends with curly hair who try to get their tresses
> to lay straight. My hair is medium blonde--a real pretty golden color, but
> I've longed for anything from black to red (and never quite had the nerve
> to do it, thank God). I'm tall; I want to be shorter (not much I can do
> about that). Why is it we always want what we don't have? An electric kiln
> is a wonderful tool. Why not just appreciate it for what it is?
>
> Cindy Strnad
> Earthen Vessels
> Custer, SD
> USA http://blackhills-info.com/a/cindys/menu.htm
>
With so many clayarters wanting to reduce in an
electric kiln, why isn't there a manufacturer in
the US who will build one? A few years ago while teaching in Denmark at an art
this magnificant electric kiln with element coils
about an inch in diameter and a good 3/8" thick wire.
It had a clamped tight front loading door as well as a small opening in
the top. There were two tunnels running completely
through the bottom soft bricks with tiny holes
exiting into the kiln. At the appropriate time
a wax candle could be shoved into the tunnel, a
brick covered the hole in the top, and voila, a
smokeless reduction. This was about a 10 cft
kiln run on 3 phase electric, but they also had them
on their version of 220 v. Their catalog showed
a price of about $3,000 US back in 1987 for this
size, and less for smaller versions. Many potters
used these kilns, some even using wood for smoking.
However, the cost of shipping would be prohibitive.
Why can't they make these here? I bought a
Reduction Production Kiln when they first came out
and had a blast doing reduction with charcoal in a
pan under the kiln floor. They went out of busi-
ness before long, rumored to be because of bad
business practices. The kiln was a top loader with
cast lid and walls. It would have been better with
soft bricks in my opinion. I sold this kiln to a friend when I moved who is
still using it for regular firing but the lid is
cracking open. Can we get some-
thing get going with the kiln mfgrs. about
building this type kiln?
Bonnie Staffel
bstaffel@freeway.net
>
-----
See the original message at http://www.egroups.com/list/clayart/?start=33029
--
Free e-mail group hosting at http://www.eGroups.com/
Lynn Rank on fri 9 oct 98
Well, been meaning to address this, seems like it is very important only if
you have an electric kiln and want to reduce, which was what I had. My
teacher Vivika Heino, told me to put in pieces of wood ( small 4-6inches
long ) in through the peep hole every 10 minutes or so. Coat the pieces
with shellac. Do this around 1600 for a body reduction and again around the
temperature you are going to. I think the higher one was done for 10 to 20
minutes or so nearing the highest temperature you are going to.
I did this for a long time. I couldn't see any real element damage. She
always said any carbin left would burn out in the next bisque. Seems like
it did and the end results were like firing with wood. Just took lots of
time and "Being There' with the kiln. (Which firing does anyway.)
Lynn in Ca
-----Original Message-----: Ceramic Arts Discussion List
[mailto:CLAYART@LSV.UKY.EDU] On Behalf Of Vince Pitelka
Sent: Thursday, October 08, 1998 6:51 AM
To: CLAYART@LSV.UKY.EDU
Subject: Re: Electric reduction
----------------------------Original message----------------------------
At 09:09 AM 10/7/98 -0400, you wrote:
>----------------------------Original message----------------------------
>Donn Buchfinck wrote:
>>
>> I do not realy think that reducing an electric kiln will hurt the
elements,
>> Ok I'm not an element person but what I thought made the elements go bad
was them oxidising.
Peter Hammer wrote:
>
>A reasonable thought, but wrong. Most elements (like aluminium and
>stainless steel) rely on a surface layer of oxide for protection.
Peter -
I'm not sure you can technically say this is wrong. It is true that Kanthal
elements build up a layer of oxidation which protects them, but that happens
only if they stop oxidizing. If you erode that layer of oxidation, they
continue to oxidize deeper into the core metal, and eventually they fail.
Is Chris from Euclid's listening, and if so, am I correct in this
assumption?
- Vince
Vince Pitelka - vpitelka@DeKalb.net
Home 615/597-5376, work 615/597-6801, fax 615/597-6803
Appalachian Center for Crafts
Tennessee Technological University
1560 Craft Center Drive, Smithville TN 37166
Earl Brunner on fri 9 oct 98
In a message dated 10/8/98 9:27:30 AM Pacific Daylight Time,
kinoko@okjunc2.junction.net writes:
<< ----------------------------Original message----------------------------
>>I have heard that people put moth balls it thier kiln
>>this could be an urban legend >>
This is not an urban legend, however several texts in the early 60's suggested
this. Rhodes notes in Clay and Glazes for the Potter 1974 pg 272 that this
is a dangerous practice due to the hazardous/toxic fumes given off.
Bad idea
EarlBrunner
Lynn Rank on wed 14 oct 98
As Otto Heino told me and my husband, the secret to good electric firing is
Layering the Glazes. Have found that is not always the case, but over and
over another usually doesn't hurt.
Lynn in CA ( with no reducton)
-----Original Message-----
From: Ceramic Arts Discussion List [mailto:CLAYART@LSV.UKY.EDU] On Behalf Of
Cindy
Sent: Thursday, October 08, 1998 6:39 AM
To: CLAYART@LSV.UKY.EDU
Subject: Re: Electric reduction
----------------------------Original message----------------------------
Just a short comment . . .
Why not let your electric kiln fire the best electric-fired pots it can?
Electric kilns do all sorts of wonderful things which are difficult, if not
impossible to accomplish in a fuel-burning kiln. I would like to have a
fuel kiln, and will have one when things come together, but in the mean
time, I choose to explore the limitless possibilities inherent in oxidation
firing. There's plenty here for me yet to learn.
I have long, straight hair. For years, I tried to get it to curl. Silly
girl--I have plenty of friends with curly hair who try to get their tresses
to lay straight. My hair is medium blonde--a real pretty golden color, but
I've longed for anything from black to red (and never quite had the nerve
to do it, thank God). I'm tall; I want to be shorter (not much I can do
about that). Why is it we always want what we don't have? An electric kiln
is a wonderful tool. Why not just appreciate it for what it is?
Cindy Strnad
Earthen Vessels
Custer, SD
USA http://blackhills-info.com/a/cindys/menu.htm
John H. Rodgers on tue 20 oct 98
-- [ From: John H. Rodgers * EMC.Ver #2.5.02 ] --
From an earlier post >>""The decreased element life is the "cost of doing
business"
I agree with this comment completely. Depending on the size of the kiln
element replacement costs will vary, but essentially you just factor the
cost into cost of production, adjusting your sales price accordingly.
Element replacement in my own kiln, a medium sized Duncan, is about $125.
Sell four or five pots or bowls and replacement cost is recovered.
So if you want to do electric reduction....No Big Deal!!
John Rodgers
In Alabama where it is 78F and thinking about home in Alaska where it is 30F
and the first snow has fallen.
--
Vince Pitelka on mon 8 feb 99
>I've read that the kiln elements are a very heavy weight gauge, much more so
>than any of the elements we use in our USA kilns and can take the reduction in
>the kiln with no adverse effects [in other words they build them to last}
>hope this answers your question. Dave
Electric reduction kilns are usually equipped with globar or kanthal rod
elements, which are very resistant to reduction effects. The down side is
that these elements require a very high amperage regulated power supply. I
have a friend in St.Louis who is a production glass blower, and uses an
electric melt furnace with kanthal rod elements - one in each corner of the
chamber. The furnace and power supply cost around $25,000. For him, it is
well worth it. It would be hard to justify for electric reduction in
ceramics. Remember, you cannot claim environmental benefit by using an
electric kiln, because electric generation plants are often among the worst
of poluters.
- Vince
Vince Pitelka - vpitelka@DeKalb.net
Home 615/597-5376, work 615/597-6801, fax 615/597-6803
Appalachian Center for Crafts
Tennessee Technological University
1560 Craft Center Drive, Smithville TN 37166
Jim Murphy on thu 15 jun 06
Hi Ivor,
Here's the scenario [from a gas-filled microscopic bubble's perspective] ..=
.
We understand from Charles' and Boyle's Laws [relating gas Pressure,
Temperature and Volume], the "gas" temperature - inside a bubble - may be
hotter or cooler than the surrounding molten matrix depending on whether th=
e
gas-filled bubble is "expanding" or "contracting".
Therefore, a "thermal gradient" is established between bubble internal
cavity and external "molten" surrounding area. [Just what's needed for
"condensation", i.e., water formation ;o)]
Chemical reactions inside & around these "microscopic" bubbles [containing
CO2, CO, water-vapor, etc.] are very valuable for Reduction effects where C=
O
and Hydrogen concentration are important.
Here's the two important Reduction-based chemical reactions:
CO2 -> CO + 1/2O2
CO + H2O -> CO2 + H2
So briefly, when I refer to "condensation - during cooling", I'm suggesting
- with careful kiln temperature control - it may be desirable to keep the
bubbles "in solution" to maximize the "time" for BOTH of the above chemical
reactions to occur [rather than heat-up and/or cool too fast and "pop" all
the bubbles at the glaze surface].
Under this condensation-scenario, it's "possible" [inside bubble cavities]
to create "new" chemical-water which would thermally split [@ ~1000=BAC] -
almost instantaneously - feeding more Hydrogen to the bubble/molten
interface.
Best wishes,
Jim
On Thu, Jun 15, 2006, 12:13 AM, Ivor wrote:
> <> attention to revealing the "secrets" of Electric Reduction.>>
>
> Dear Jim Murphy,
> Perhaps you might like to enlarge on this statement and enlighten us all
> about how you would achieve this and explain the chemistry involved.
Ivor and Olive Lewis on thu 15 jun 06
<attention to revealing the "secrets" of Electric Reduction.>>
Dear Jim Murphy,
Perhaps you might like to enlarge on this statement and enlighten us all =
about how you would achieve this and explain the chemistry involved.
I'm sure all the people who fire to Cone 6 Electric would be interested =
in achieving reduction transmutation colours.
Best regards,
Ivor Lewis.
Redhill,
South Australia.
Lee Love on fri 16 jun 06
On 6/15/06, Ivor and Olive Lewis wrote:
> Perhaps you might like to enlarge on this statement and enlighten us
>all about how you would achieve this and explain the chemistry involved.
> I'm sure all the people who fire to Cone 6 Electric would be interested in >achieving reduction transmutation colours.
Reduction in an electric kiln is a "no-brainer."
At the Mashiko Pottery Festival this spring, elecric reduction was
probably the majority firing method. The potters on either side of
me fired in a normal Japanese type electric kiln (with heavy
elements.) For reduction, they fired a sagger full of charcoal.
You can buy elecric kilns at Joyful Honda Home Center that have small
gas burners that will make a reduction atmosphere. The other way,
is through a charcoal box that is under the kiln (saves space that a
sagger takes up.
The main thing that holds us back in the states are the light
coil type elements. Japanese electric kilns cost a lot more than
American kilns. But they are better insulated and are of industrial
quality.
--
Lee in Mashiko, Japan
http://mashiko.org
My google Notebooks:
http://tinyurl.com/e5p3n
"The accessibility of the handmade object in today's world seems vital
and radical, and hopefully tempers our hunger for 'progress' and
rationality" - , Michael Kline
Dave Finkelnburg on sat 17 jun 06
Jim and Ivor,
Your speculations are interesting! :-)
I doubt it's possible to have any significant
amount of elemental carbon present at a temperature at
which a glaze is molten if oxygen is also present.
Instead, you will have CO2. In the case of reduction
you have an absence of O2.
There are, in the literature, published diffusion
constants for different gases in a silicate glass
matrix. Unfortunately, the glasses are usually of
window glass composition instead of glaze composition,
so I'm sure the diffusion constants are only partially
applicable, but it can give some clues as to how
mobile a particular gas can be through a molten glaze.
Good potting,
Dave Finkelnburg
--- Jim Murphy wrote:
> FWIW, I said keep the "bubbles" in solution [which
> is somewhat different
> from saying keep ALL "the gases" in solution] :o).
>
> Looking at fired "Chun" glaze, e.g., those "tiny
> bubbles" [causing
> opalescense] have me wondering "what type of 'air'
> was trapped inside those
> bubbles [and what escaped] ?"
>
> Perhaps mostly just "Oxygen" remains in these
> bubbles, while "Carbon" &
> "Hydrogen" remain outside the bubbles performing
> their Reduction magic on
> metallic atoms in the viscous melt. I understand ...
> in gas-Reduction, an
> external fuel source provides Carbon, CO, etc.
>
> Thinking "outside-the-box", could something similar
> be created in "Electric
> Reduction"? If claybody & glaze recipe were adjusted
> to "source" ample
> "Carbon" [from carbonates, Dolomite, etc.] &
> "Hydrogen" [from water, etc.]
> ... AND the firing were properly controlled for
> bubble retention ... could
> "Carbon" and "Hydrogen" diffuse FROM trapped bubbles
> leaving mostly just
> "Oxygen" inside the bubbles.
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Ivor and Olive Lewis on sat 17 jun 06
Dear Lee Love,=20
Have to agree with you, Electric reduction is a "No Brainer" whatever =
that might mean to populus at large, but you are missing the point ! ! ! =
.
From time to time there are reports of reduction type results from an =
electric kiln without the intervention of Charcoal filled saggars or a =
fuel gas being fed into the kiln.
Your task is to explain that phenomenon. Are you able to think outside =
the square ? ?
Best regards,
Ivor Lewis.
Redhill,
South Australia.
No quote day
Ivor and Olive Lewis on sat 17 jun 06
Dear Jim Murphy,=20
If the gases are in solution in the vitreous melt then there will be no =
bubbles but your proposition may have merit. Have you checked using =
pV=3D nRT
By the way, your reaction "...CO2 -> CO + 1/2O2..." is not spontaneous. =
Perhaps you can explain why. Do you know the equilibrium temperature ?
The initiation temperature for your second equation, the "Shift =
Reaction", "CO + H2O -> CO2 + H2" is quite low, about 400 deg C and the =
gases must by catalysed by being passed through beds of Iron Oxide and =
Copper Oxide. Again, not the sort of spontaneous event we rely on when =
we are firing a load of pots.
Nevertheless, interesting to exercise our minds with a little idle =
speculation.
Best regards,
Ivor.
Jim Murphy on sat 17 jun 06
Hi Ivor,
FWIW, I said keep the "bubbles" in solution [which is somewhat different
from saying keep ALL "the gases" in solution] :o).
Looking at fired "Chun" glaze, e.g., those "tiny bubbles" [causing
opalescense] have me wondering "what type of 'air' was trapped inside those
bubbles [and what escaped] ?"
Perhaps mostly just "Oxygen" remains in these bubbles, while "Carbon" &
"Hydrogen" remain outside the bubbles performing their Reduction magic on
metallic atoms in the viscous melt. I understand ... in gas-Reduction, an
external fuel source provides Carbon, CO, etc.
Thinking "outside-the-box", could something similar be created in "Electric
Reduction"? If claybody & glaze recipe were adjusted to "source" ample
"Carbon" [from carbonates, Dolomite, etc.] & "Hydrogen" [from water, etc.]
... AND the firing were properly controlled for bubble retention ... could
"Carbon" and "Hydrogen" diffuse FROM trapped bubbles leaving mostly just
"Oxygen" inside the bubbles.
Perhaps the premise is incorrect ... if not though ......................
;o)
Best wishes,
Jim
>From: Ivor and Olive Lewis
>Date: Sat, Jun 17, 2006, 1:46 AM
> If the gases are in solution in the vitreous melt then there will be no
> bubbles but your proposition may have merit. Have you checked using pV= nRT
>
> By the way, your reaction "...CO2 -> CO + 1/2O2..." is not spontaneous.
> Perhaps you can explain why. Do you know the equilibrium temperature ?
> The initiation temperature for your second equation, the "Shift Reaction",
> "CO + H2O -> CO2 + H2" is quite low, about 400 deg C and the gases must by
> catalysed by being passed through beds of Iron Oxide and Copper Oxide.
> Again, not the sort of spontaneous event we rely on when we are firing a
> load of pots.
Edouard Bastarache Inc. on sat 17 jun 06
Hello Ivor,
how about using finely grained Carbon in glazes to
create reduction effects in an electric kiln.
Later,
Edouard Bastarache
Membre de La French Connection
Member of The French Connection
Sorel-Tracy
Quebec
edouardb@sorel-tracy.qc.ca
www.sorel-tracy.qc.ca/~edouardb/Welcome.html
http://perso.wanadoo.fr/smart2000/index.htm
http://www.flickr.com/photos/potier/
http://oldringer.blogspot.com/
http://albertpeintures.blogspot.com/
Edouard Bastarache Inc. on sun 18 jun 06
Ivor and Dave,
I have been using a waste material form the
anti-pollution system
of a steel-melting department of a local facility
producing mild
steel.
The stuff already contains a certain amount of
carbon and that is where
my hypothesis comes from.
I have been using it for many years in clays and
glazes fired at cone 9½
and 04.
Here is my famous (Veena) QIT Red Dust :
QIT stands for Quebec Iron and Titanium. QIT owns
an ilmenite mine in
northeastern Quebec.
The ore is shipped to Tracy where it is processed
to titanium dioxide slags,
iron pigs, steel billets, iron and steel powders
and steel autoparts.
This dust comes from the dust collecting system of
the steelmelting
department and has the following general formula :
FE2O3……………… 85%
SIO2 ………………….5.0%
CAO ………………….5.0%
MGO …………………1.0%
ZNO ………………….2.0%
CARBON ……….……2.0%
TOTAL ………...….…100%
It was 170 mesh sieved.
Later,
Edouard Bastarache
Membre de La French Connection
Member of The French Connection
Sorel-Tracy
Quebec
edouardb@sorel-tracy.qc.ca
www.sorel-tracy.qc.ca/~edouardb/Welcome.html
http://perso.wanadoo.fr/smart2000/index.htm
http://www.flickr.com/photos/potier/
http://oldringer.blogspot.com/
http://albertpeintures.blogspot.com/
Ivor and Olive Lewis on sun 18 jun 06
Dear Edouard,
An interesting question <glazes to create reduction effects in an electric kiln.>>
Graphite powder is easy enough to get hold of, so is ground charcoal. =
Since I do not have an electric kiln why don't you go ahead and be the =
first to try it.
Having tried to make marks on pottery with very soft graphite pencils =
only to find that they disappear, I am not sure it would work. But a =
trial is worth the effort.
But it does get us away from a spontaneous event which is a function of =
the ingredients of the glaze to an engineered event.
Great to have your input.
Best regards,
Ivor
Lee Love on sun 18 jun 06
On 6/18/06, Edouard Bastarache Inc. wrote:
> Hello Ivor,
>
> how about using finely grained Carbon in glazes to
> create reduction effects in an electric kiln.
Eduoard, All my clay has organics in it. The shigaraki with
feldspar in it, stinks to high heaven in the summer time, b if I don't
change the water every day.
They say the ricestraw ash and the rice hull ash is best if
it has black in it, so it has some carbon in it. But I haven't
found any reduction effects from the carbon in the ash.
--
Lee in Mashiko, Japan
http://mashiko.org
My google Notebooks:
http://tinyurl.com/e5p3n
"The accessibility of the handmade object in today's world seems vital
and radical, and hopefully tempers our hunger for 'progress' and
rationality" - , Michael Kline
Lee Love on sun 18 jun 06
On 6/17/06, Ivor and Olive Lewis wrote:
>
> Your task is to explain that phenomenon.
No, that is YOUR task.
> Are you able to think outside the square ? ?
Your task is to do some actual tests. Theory will only take
you so far. If theory keeps you from actually doing some firing.
It is a waste of time.
--
Lee in Mashiko, Japan
http://mashiko.org
My google Notebooks:
http://tinyurl.com/e5p3n
"The accessibility of the handmade object in today's world seems vital
and radical, and hopefully tempers our hunger for 'progress' and
rationality" - , Michael Kline
sincultura13 on mon 19 jun 06
Last year I did some experiments with Silicone carbide on low in
copper clear leaded and leadless glazes at cone 04 and got some
reddish color in different degrees and hues mostly behind a
torquoise or grayish tinted surface... I haven't had the time try it
again...
There's information around the net about a couple of people who have
been able to get it right. Some kind folk here, forget the name,
sent me some artcicles from the fifties and Tom Buck wrote me an
email with suggestions that I couldn't try due to lack of access to
equipment and materials... If I remember right he suggested I used
1000mesh silicone carbide and that I ballmilled the glaze...
Later,
Sincultura13
--- In clayart@yahoogroups.com, Ivor and Olive Lewis
wrote:
>
> Dear Edouard,
>
> An interesting question <in glazes to create reduction effects in an electric kiln.>>
>
> Graphite powder is easy enough to get hold of, so is ground
charcoal. Since I do not have an electric kiln why don't you go
ahead and be the first to try it.
>
> Having tried to make marks on pottery with very soft graphite
pencils only to find that they disappear, I am not sure it would
work. But a trial is worth the effort.
>
> But it does get us away from a spontaneous event which is a
function of the ingredients of the glaze to an engineered event.
>
> Great to have your input.
>
> Best regards,
>
> Ivor
>
>
_____________________________________________________________________
_________
> Send postings to clayart@...
>
> 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@...
>
Ivor and Olive Lewis on mon 19 jun 06
Dear Lee Love,=20
I regret that I do not have an Electric Kiln. But perhaps someone who =
has might be willing to consider firing some samples and reporting on =
their experience.
Best regards,
Ivor Lewis.
Redhill,
South Australia.
Ivor and Olive Lewis on mon 19 jun 06
Dear Dave Finkelnburg,=20
I am looking forward to reading the article in the next INTERCERAM. The =
promise is to reveal the analysis of gas in occluded bubbles.
As you know, the Chemistry of Carbon and its oxides is rather complex.
Best regards,
Ivor Lewis.
Redhill,
South Australia.
Ivor and Olive Lewis on tue 20 jun 06
Dear Edouard Bastarache,
Interesting stuff. Steel smelting is a complex process. If the residue =
you are using is a final product from the processing of mild steel then =
it is possible that a fraction of the residue is in the form of Iron =
Carbide. This would tend to have greater stability than free carbon.=20
You ought to try to get some of the floor sweepings from Deloro =
Stellite" Cobalt Smelter. Their operation must be fairly close to you.=20
Thanks for the information.
Best regards,
Ivor.
Lee Love on tue 20 jun 06
On 6/19/06, Ivor and Olive Lewis wrote:
> Dear Lee Love,
>
> I regret that I do not have an Electric Kiln. But perhaps someone who has might be willing >to consider firing some samples and reporting on their experience.
About half the crew that is coming to Mashiko for a week and staying
at Furuki's here in Mashiko have arrived. In Furuki's workshop,
they have a microwave electric kiln. But I think they mostly bisque
in it.
Hey, what would be cool is a hybrid microwave/wood kiln. ;^)
--
Lee in Mashiko, Japan
http://mashiko.org
My google Notebooks:
http://tinyurl.com/e5p3n
"The accessibility of the handmade object in today's world seems vital
and radical, and hopefully tempers our hunger for 'progress' and
rationality" - , Michael Kline
Edouard Bastarache Inc. on tue 20 jun 06
Hello Ivor,
for more than 10 years I have been using this
waste material
as a substitute for Fe2O3.
My first hypothesis is that the Carbon helps in my
different
Iron Reds, an other glazes, acting as a local
"reductor".
Contrary to David's opinion, the Carbon in this
stuff "had all the
chances" to be oxidized to CO2 taking into account
the very high
temperature reached in steel-melting and the fact
that Oxygen is often
times introduced into the furnace during the
firing.
My second hypothesis is that this stuff could used
as a very fine
grained chamotte in low-fire clays in which up to
7% Fe2O3
may be added. In fact, we have "seen" this effect
when throwing
these clays as compared to those containing Fe2O3.
To bad we could not measured this in a parametric
way.
Later,
Edouard Bastarache
Membre de La French Connection
Member of The French Connection
Sorel-Tracy
Quebec
edouardb@sorel-tracy.qc.ca
www.sorel-tracy.qc.ca/~edouardb/Welcome.html
http://perso.wanadoo.fr/smart2000/index.htm
http://www.flickr.com/photos/potier/
http://oldringer.blogspot.com/
http://albertpeintures.blogspot.com/
----- Original Message -----
From: "Ivor and Olive Lewis"
To:
Sent: Tuesday, June 20, 2006 3:20 AM
Subject: Re: Electric Reduction
Dear Edouard Bastarache,
Interesting stuff. Steel smelting is a complex
process. If the residue you are using is a final
product from the processing of mild steel then it
is possible that a fraction of the residue is in
the form of Iron Carbide. This would tend to have
greater stability than free carbon.
You ought to try to get some of the floor
sweepings from Deloro Stellite" Cobalt Smelter.
Their operation must be fairly close to you.
Thanks for the information.
Best regards,
Ivor.
______________________________________________________________________________
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.
Ivor and Olive Lewis on wed 21 jun 06
Dear Edouard Bastarache,
As I suggest in an earlier post we should not forget that during the =
preparation of Mild Steel Carbonaceous materials are added to the melt. =
Carbon is taken into solution and takes part in a chemical reaction the =
result of which is Iron Carbide (Fe3C). Mild steel has about 0.20 =
%carbon. As you say, in the more modern processes, Oxygen is blown into =
the molten steel, a spectacular sight, to remove excess carbon (and =
Phosphorus and Sulphur). It removes Iron as well. Perhaps both are still =
combined when the metal solidifies and sets as a fine powder that comes =
to you.
Yes, if Silicon Carbide can act as a reducing agent should anything =
prevent iron carbide from acting in a similar fashion ? ?
Best regards,
Ivor Lewis.
Redhill,
South Australia.
Angela Davis on sun 9 dec 07
Hello David, sounds interesting.
Show me some pots!
Angela Davis
In warm and damp Homosassa, the clay just won't dry.
----- Original Message -----
From: "David Turner"
To:
Sent: Sunday, December 09, 2007 5:09 PM
Subject: electric reduction
> hi ...for the past 4 years i have been conducting experiments with
> electric-reduction and finally, after many loads of half-green and half-
> red pots, my last three firings have produced fully developed copper reds
> top to bottom, front to back, just like the ad's in ceramics monthly. what
> i wanted to know is if anyone out there is interested in electric
> reduction as an alternative to gas and wood firings,or if any one else is
> doing electric reduction sucessfully. (besides nils lou) .....it's lonely
> out here .
> i am designing a line of prototype kilns and have a kiln manufacturer
> willing to build them for me, but to get the whole thing rolling my wife
> insists that we find out if there would be a market for this type of
> kiln. anyone interested please e-mail me at
> earthnouveau@gmail.com
>
> hope to hear from you all
> 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
>
>
> --
> No virus found in this incoming message.
> Checked by AVG Free Edition.
> Version: 7.5.503 / Virus Database: 269.16.17/1179 - Release Date:
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>
Chaeli Sullivan on sun 9 dec 07
So David
Are you saying that it's the kiln design and not necessarily the glaze ingredients that will produce reduction in an electric firing?
Chae
David Turner wrote:
hi ...for the past 4 years i have been conducting experiments with
electric-reduction and finally, after many loads of half-green and half-
red pots, my last three firings have produced fully developed copper reds
top to bottom, front to back, just like the ad's in ceramics monthly. what
i wanted to know is if anyone out there is interested in electric
reduction as an alternative to gas and wood firings,or if any one else is
doing electric reduction sucessfully. (besides nils lou) .....it's lonely
out here .
i am designing a line of prototype kilns and have a kiln manufacturer
willing to build them for me, but to get the whole thing rolling my wife
insists that we find out if there would be a market for this type of
kiln. anyone interested please e-mail me at
earthnouveau@gmail.com
hope to hear from you all
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
---------------------------------
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Wendy Peck on sun 9 dec 07
Hi David,
Do you have an approximate cost for a kiln of a particular size? I would
defintiely be interested in a reducing electric kiln, depending on the
retail price.
Thanks,
Wendy
----- Original Message -----
From: "David Turner"
To:
Sent: Sunday, December 09, 2007 4:09 PM
Subject: electric reduction
> hi ...for the past 4 years i have been conducting experiments with
> electric-reduction and finally, after many loads of half-green and half-
> red pots, my last three firings have produced fully developed copper reds
> top to bottom, front to back, just like the ad's in ceramics monthly. what
> i wanted to know is if anyone out there is interested in electric
> reduction as an alternative to gas and wood firings,or if any one else is
> doing electric reduction sucessfully. (besides nils lou) .....it's lonely
> out here .
> i am designing a line of prototype kilns and have a kiln manufacturer
> willing to build them for me, but to get the whole thing rolling my wife
> insists that we find out if there would be a market for this type of
> kiln. anyone interested please e-mail me at
> earthnouveau@gmail.com
>
> hope to hear from you all
> 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
>
David Turner on sun 9 dec 07
hi ...for the past 4 years i have been conducting experiments with
electric-reduction and finally, after many loads of half-green and half-
red pots, my last three firings have produced fully developed copper reds
top to bottom, front to back, just like the ad's in ceramics monthly. what
i wanted to know is if anyone out there is interested in electric
reduction as an alternative to gas and wood firings,or if any one else is
doing electric reduction sucessfully. (besides nils lou) .....it's lonely
out here .
i am designing a line of prototype kilns and have a kiln manufacturer
willing to build them for me, but to get the whole thing rolling my wife
insists that we find out if there would be a market for this type of
kiln. anyone interested please e-mail me at
earthnouveau@gmail.com
hope to hear from you all
david turner
Timothy Joko-Veltman on mon 10 dec 07
I'm interested (though not sure I could ever get one, what with living
on another continent).
If it's not local reduction (ie., not in individual glazes with
something like silicon carbide), then what kind of elements are you
using? (Reduction atmospheres are not very kind to most electrical
elements.)
Tim
On Dec 9, 2007 5:09 PM, David Turner wrote:
> hi ...for the past 4 years i have been conducting experiments with
> electric-reduction and finally, after many loads of half-green and half-
> red pots, my last three firings have produced fully developed copper reds
> top to bottom, front to back, just like the ad's in ceramics monthly. what
> i wanted to know is if anyone out there is interested in electric
> reduction as an alternative to gas and wood firings,or if any one else is
> doing electric reduction sucessfully. (besides nils lou) .....it's lonely
> out here .
> i am designing a line of prototype kilns and have a kiln manufacturer
> willing to build them for me, but to get the whole thing rolling my wife
> insists that we find out if there would be a market for this type of
> kiln. anyone interested please e-mail me at
> earthnouveau@gmail.com
>
> hope to hear from you all
> 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
>
Earl Brunner on mon 10 dec 07
I agree with Timothy, interest would probably depend on life expectancy of the elements. Info on what you have done to get around that problem would go a long way towards determining interest. If element life is acceptable, then I would expect there to be "some" interest, whether or not there is enough to justify the production remains to be seen.
Earl Brunner (incase my auto signature isn't working)
----- Original Message ----
From: Timothy Joko-Veltman
To: CLAYART@LSV.CERAMICS.ORG
Sent: Monday, December 10, 2007 10:14:51 AM
Subject: Re: electric reduction
I'm interested (though not sure I could ever get one, what with living
on another continent).
If it's not local reduction (ie., not in individual glazes with
something like silicon carbide), then what kind of elements are you
using? (Reduction atmospheres are not very kind to most electrical
elements.)
Tim
On Dec 9, 2007 5:09 PM, David Turner wrote:
> hi ...for the past 4 years i have been conducting experiments with
> electric-reduction and finally, after many loads of half-green and half-
> red pots, my last three firings have produced fully developed copper reds
> top to bottom, front to back, just like the ad's in ceramics monthly. what
> i wanted to know is if anyone out there is interested in electric
> reduction as an alternative to gas and wood firings,or if any one else is
> doing electric reduction sucessfully. (besides nils lou) .....it's lonely
> out here .
Earth Nouveau on sun 16 dec 07
hi Chaeli....
I use standard glaze formulas without the addition of silicon carbide.
The reduction is created from 1600 degrees to shut off just like in regular
gas firings.The modifications in the kiln itself are minimal and only
facilitate the insertion of fuel to the chamber .The most important part
of the design is getting safe reduction in a basement studio.I have
installed special partitions for containing the fumes and extra vents to
remove them.I wouldn't advise anyone to try this without first taking the
necessary precautions of isolating the fumes by building a special kiln
enclosure (i.e. kiln room) ,installing a adequate vent system to remove the
fumes, and having a carbon monoxide detector in the kiln room as well as
outside of it.
be safe
David Turner
On Dec 9, 2007 11:50 PM, Chaeli Sullivan wrote:
> So David
> Are you saying that it's the kiln design and not necessarily the glaze
> ingredients that will produce reduction in an electric firing?
> Chae
>
> David Turner wrote:
> hi ...for the past 4 years i have been conducting experiments with
> electric-reduction and finally, after many loads of half-green and half-
> red pots, my last three firings have produced fully developed copper reds
> top to bottom, front to back, just like the ad's in ceramics monthly. what
> i wanted to know is if anyone out there is interested in electric
> reduction as an alternative to gas and wood firings,or if any one else is
> doing electric reduction sucessfully. (besides nils lou) .....it's lonely
> out here .
> i am designing a line of prototype kilns and have a kiln manufacturer
> willing to build them for me, but to get the whole thing rolling my wife
> insists that we find out if there would be a market for this type of
> kiln. anyone interested please e-mail me at
> earthnouveau@gmail.com
>
> hope to hear from you all
> david turner
>
>
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Chaeli Sullivan on thu 20 dec 07
David
Sorry it's taken me so long to reply.
Reduction in an electric kiln fascinates me. That you have done it
successfully is awesome.
Saw an arrangement on Lee Love's site (might have been Vince's) (with
Christmas nearly here and all that entails my mind is muddled) where a gas
couplet appears to be attached to the peephole.
This sounds very similar to what you are describing below.
Thank you about the precautions on the fumes . . . wouldn't necessarily
have thought about that.
Chae
On Sun, 16 Dec 2007 06:50:09 -0500, Earth Nouveau
wrote:
>hi Chaeli....
> I use standard glaze formulas without the addition of silicon carbide.
> The reduction is created from 1600 degrees to shut off just like in
regular
>gas firings.The modifications in the kiln itself are minimal and only
>facilitate the insertion of fuel to the chamber .The most important part
>of the design is getting safe reduction in a basement studio.I have
>installed special partitions for containing the fumes and extra vents to
>remove them.I wouldn't advise anyone to try this without first taking the
>necessary precautions of isolating the fumes by building a special kiln
>enclosure (i.e. kiln room) ,installing a adequate vent system to remove
the
>fumes, and having a carbon monoxide detector in the kiln room as well as
>outside of it.
> be safe
> David Turner
>
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