Connie Christensen on sat 29 jan 05
Hi everyone
I was asked to send this question to clayart to see if this can be done.
Can you use a kiln for both gas reduction and soda firings? I would think
that this would not be a good idea because of the residual soda and it's
affect on the following gas reduction firings, but I've never fired with
soda, only salt.
I would appreciate any comments on this.
Thanks
Connie Christensen
Arvada, CO
www.conniechristensen.com
Vince Pitelka on sun 30 jan 05
> Can you use a kiln for both gas reduction and soda firings? I would think
> that this would not be a good idea because of the residual soda and it's
> affect on the following gas reduction firings, but I've never fired with
> soda, only salt.
Connie -
Once a soda kiln, always a soda kiln. It's just the same as with salt.
However, residual soda is very nice, and if I could only have one gas kiln,
I'd make it a soda kiln and sometimes do residual firings without adding
soda, in order to emphasize glaze surfaces. But once a kiln has been used
as a soda kiln, you could not get the kind of clean-atmosphere results you
can get from a straight oxidation or reduction kiln.
Best wishes -
- Vince
Vince Pitelka
Appalachian Center for Craft, Tennessee Technological University
Smithville TN 37166, 615/597-6801 x111
vpitelka@dtccom.net, wpitelka@tntech.edu
http://iweb.tntech.edu/wpitelka/
http://www.tntech.edu/craftcenter/
Connie Christensen on sun 30 jan 05
> Connie -
> Once a soda kiln, always a soda kiln. It's just the same as with salt.
> However, residual soda is very nice, and if I could only have one gas
kiln,
> I'd make it a soda kiln and sometimes do residual firings without adding
> soda, in order to emphasize glaze surfaces. But once a kiln has been used
> as a soda kiln, you could not get the kind of clean-atmosphere results you
> can get from a straight oxidation or reduction kiln.
> Best wishes -
> - Vince
Hi Vince, thanks for your answer. I feel vindicated - or is it vincedicated.
Connie
Connie Christensen on mon 31 jan 05
Hank Murrow wrote:
Dear Dan and Connie;
>
> I have successfully fired both ways in salt/soda kilns. The secret in
> my case was the Al Bain's suggestion of casting high-alumina 'pans' in
> the fireboxes to hold the melting sodium while it vaporized. If you
> don't get molten sodium down between the joints in the brickwork, there
> is little to glaze the pots in a subsequent salt/soda-less firing....>
Gosh Hank, I liked Vince's answer better, yours will only encourage them :)
It would be fine if it was one person experimenting on their own kiln, this
is a kiln they are wanting to build for a guild with quite a few people
using it - mostly for gas reduction and some people would also like to soda
fire. Since I have my own kiln, it won't affect me, but I sure don't want to
see a bunch of unhappy people in the guild because soda is contaminating
their firings. They were trying to save the cost of building 2 kilns and
someone had told them it would work.
So even though this has worked for you, I think one would have to be
extremely careful about the way they put the soda in the kiln and also keep
the kiln shelves very clean or have 2 sets of shelves. I don't see this
working with a group of people who have varying levels of messy to tidy to
downright anal habits (I think I can be classified in all 3 categories by
the way).
Thanks for answering and I'll give your response to the person who wanted me
to ask the question.
Connie Christensen
Arvada, CO
www.conniechristensen.com
Dan Hill on mon 31 jan 05
Hello Connie
I believe that it is be possible to soda fire and do standard reduction in
the same kiln. The next kiln I build will be constructed with high alumina
IFBs and coated with ITC on the inside to resist the soda. I would say that
such a kiln would last indifinitely. There would likely be some residual
soda from the shelves etc. but it wouldn't be significant.
Has anyone out there tried this yet?
Dan Hill
Hill Pottery
Wilno, Ontario, Canada
Hank Murrow on mon 31 jan 05
On Jan 31, 2005, at 5:26 AM, Dan Hill wrote:
> Hello Connie
> I believe that it is be possible to soda fire and do standard
> reduction in
> the same kiln. The next kiln I build will be constructed with high
> alumina
> IFBs and coated with ITC on the inside to resist the soda. I would say
> that
> such a kiln would last indifinitely. There would likely be some
> residual
> soda from the shelves etc. but it wouldn't be significant.
> Has anyone out there tried this yet?
Dear Dan and Connie;
I have successfully fired both ways in salt/soda kilns. The secret in
my case was the Al Bain's suggestion of casting high-alumina 'pans' in
the fireboxes to hold the melting sodium while it vaporized. If you
don't get molten sodium down between the joints in the brickwork, there
is little to glaze the pots in a subsequent salt/soda-less firing. We
cast them around 1" thick, with a thicker wall around the periphery to
contain the salt/soda. If you wish faster vaporisation, you can stand
soap bricks on end to act as wicks for the molten sodium. We could
actually see this wicking action during salting.
Cheers, Hank
www.murrow.biz/hank
Ivor and Olive Lewis on tue 1 feb 05
The key to answering this question is knowing the Vapour Pressure of
Sodium Carbonate. That is, the temperature at which it will boil at
atmospheric pressure.
Which raises some interesting questions because (a) I do not know that
value and (b) Kaye and Laby say it decomposes, implying that it does
not vaporise but they do not give a temperature for that chemical
reaction though no doubt, it could be computed.
However, Molten Sodium Carbonate will react with Free Silica to give
water soluble sodium silicate.
Best regards,
Ivor Lewis.
Redhill,
S. Australia.
Hank Murrow on tue 1 feb 05
Dear Connie;
The situation you describe more fully here is not the one I was
addressing. I understood it to ba primarily a soda kiln which could be
fired without soda. A reduction kiln fired occasionally with soda is
different in nature. I would not commit expensive setters to a fire in
a soda kiln. They need to build two kilns. One for regular firings in
redduction and oxidation......and one for soda/salt firings ith
occasional salt/soda-free firings. And separate setters for each.
Cheers, Hank
On Jan 31, 2005, at 8:52 PM, Connie Christensen wrote:
> Hank Murrow wrote:
> Dear Dan and Connie;
>>
>> I have successfully fired both ways in salt/soda kilns. The secret in
>> my case was the Al Bain's suggestion of casting high-alumina 'pans' in
>> the fireboxes to hold the melting sodium while it vaporized. If you
>> don't get molten sodium down between the joints in the brickwork,
>> there
>> is little to glaze the pots in a subsequent salt/soda-less firing....>
>
>
> Gosh Hank, I liked Vince's answer better, yours will only encourage
> them :)
> It would be fine if it was one person experimenting on their own kiln,
> this
> is a kiln they are wanting to build for a guild with quite a few people
> using it - mostly for gas reduction and some people would also like to
> soda
> fire. Since I have my own kiln, it won't affect me, but I sure don't
> want to
> see a bunch of unhappy people in the guild because soda is
> contaminating
> their firings. They were trying to save the cost of building 2 kilns
> and
> someone had told them it would work.
>
> So even though this has worked for you, I think one would have to be
> extremely careful about the way they put the soda in the kiln and also
> keep
> the kiln shelves very clean or have 2 sets of shelves. I don't see this
> working with a group of people who have varying levels of messy to
> tidy to
> downright anal habits (I think I can be classified in all 3 categories
> by
> the way).
>
> Thanks for answering and I'll give your response to the person who
> wanted me
> to ask the question.
> Connie Christensen
> Arvada, CO
> www.conniechristensen.com
>
> _______________________________________________________________________
> _______
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
> melpots@pclink.com.
>
>
www.murrow.biz/hank
June Perry on tue 1 feb 05
At HorseCreek pottery we have a soda kiln that we also use, successfully,
for straight gas reduction, cone 10 firings.
We have about 30 glazes we use for both soda and gas firings, i.e.
celadons, iron reds (tomato red, Mashiko), copper reds (Pete Pinnell's,
Dependable red,), shinos (Malcolm Davis Red shino, Hines,Gustin ), temmokus, a
matt black, moonlite and another rutile blue, assorted other blues, spodumene
and other matts, Leach white, greens like Oribe, Somebright, Ayumi,Reeves
green, Willy Helix, a clear matt, etc.etc.
The kiln is a soft brick composition, coated not with ITC but some other
material recommended by AP Green at the time it was built by Mckenzie Smith.
From our experience, the little bit of residual soda is not impacting the
glazes as would residual salt.
My research a few years ago, implied that soda would not impact regular
glaze firings which is why I played with it in my old Geil kiln before I moved
east and gave it away, and that coupled with what I've seen in the Horse Creek
kiln in the past couple of years, is why my new soda/wood/gas kiln that is
being built this spring, will be used for cone 10, gas reduction as well.
Regards,
June Perry
_http://www.angelfire.com/art2/shambhalapottery/_
(http://www.angelfire.com/art2/shambhalapottery/)
Hank Murrow on wed 2 feb 05
On Feb 2, 2005, at 3:23 PM, wjskw@BELLSOUTH.NET wrote:
> Hank and all:
> An interesting thought just occurred...
> Has anyone built a "standard" kiln with TWO chambers, the one to the
> rear (closest to the stack) for soda or salt, and the one in the
> "front" for regular firing? Would that keep the front chamber
> "uncontaminated"? Perhaps even with it's own burners for each
> chamber?
Dear Wayne;
Of course one could build such a two-chamber (or more) kiln such as you
describe. The problem would come in having to fire both in order to
fire one. Most potters build kilns which are too large for timely
feedback.
Cheers, Hank
www.murrow.biz/hank
Paul Herman on wed 2 feb 05
Hi Wayne,
The answer is yes, you can put a salt/soda chamber behind another
chamber. It can be preheated by the exhaust from the lower chamber. The
naborigama is an example where the upper chamber(s) could be salted
without affecting the lower chamber(s).
The woodfired kiln we use here has a lower anagama chamber and an upper
catenary salt chamber. You can see diagrams here:
http://www.greatbasinpottery.com/about_kiln.html#
best,
Paul Herman
Great Basin Pottery
Doyle, California US
http://www.greatbasinpottery.com/
----------
>From: wjskw@BELLSOUTH.NET
>To: CLAYART@LSV.CERAMICS.ORG
>Subject: Re: Using gas reduction kiln for soda firing
>Date: Wed, Feb 2, 2005, 3:23 PM
>
> Hank and all:
> An interesting thought just occurred...
> Has anyone built a "standard" kiln with TWO chambers, the one to the
> rear (closest to the stack) for soda or salt, and the one in the
> "front" for regular firing? Would that keep the front chamber
> "uncontaminated"? Perhaps even with it's own burners for each
> chamber?
> Would this even work? Excuse me if this is a stupid question,
> I just don't have the experience yet to know.
> (By standard, I mean along the lines of an MFT, or any "square"
> style "western" variety kiln)
>
> I keep looking at the multiple chambered kilns, wondering why.
>
> Wayne Seidl
wjskw@BELLSOUTH.NET on wed 2 feb 05
Hank and all:
An interesting thought just occurred...
Has anyone built a "standard" kiln with TWO chambers, the one to the
rear (closest to the stack) for soda or salt, and the one in the
"front" for regular firing? Would that keep the front chamber
"uncontaminated"? Perhaps even with it's own burners for each
chamber?=20
Would this even work? Excuse me if this is a stupid question,
I just don't have the experience yet to know.
(By standard, I mean along the lines of an MFT, or any "square"
style "western" variety kiln)
I keep looking at the multiple chambered kilns, wondering why.
Wayne Seidl
-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of Hank
Murrow
Sent: Tuesday, February 01, 2005 2:27 PM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: Using gas reduction kiln for soda firing
Dear Connie;
The situation you describe more fully here is not the one I was
addressing. I understood it to ba primarily a soda kiln which could
be
fired without soda. A reduction kiln fired occasionally with soda is
different in nature. I would not commit expensive setters to a fire
in
a soda kiln. They need to build two kilns. One for regular firings
in
redduction and oxidation......and one for soda/salt firings ith
occasional salt/soda-free firings. And separate setters for each.
Cheers, Hank
On Jan 31, 2005, at 8:52 PM, Connie Christensen wrote:
> Hank Murrow wrote:
> Dear Dan and Connie;
>>
>> I have successfully fired both ways in salt/soda kilns. The
secret in
>> my case was the Al Bain's suggestion of casting high-alumina
'pans' in
>> the fireboxes to hold the melting sodium while it vaporized. If
you
>> don't get molten sodium down between the joints in the brickwork,
>> there
>> is little to glaze the pots in a subsequent salt/soda-less
firing....>
>
>
> Gosh Hank, I liked Vince's answer better, yours will only
encourage
> them :)
> It would be fine if it was one person experimenting on their own
kiln,
> this
> is a kiln they are wanting to build for a guild with quite a few
people
> using it - mostly for gas reduction and some people would also
like to
> soda
> fire. Since I have my own kiln, it won't affect me, but I sure
don't
> want to
> see a bunch of unhappy people in the guild because soda is
> contaminating
> their firings. They were trying to save the cost of building 2
kilns
> and
> someone had told them it would work.
>
> So even though this has worked for you, I think one would have to
be
> extremely careful about the way they put the soda in the kiln and
also
> keep
> the kiln shelves very clean or have 2 sets of shelves. I don't see
this
> working with a group of people who have varying levels of messy to
> tidy to
> downright anal habits (I think I can be classified in all 3
categories
> by
> the way).
>
> Thanks for answering and I'll give your response to the person who
> wanted me
> to ask the question.
> Connie Christensen
> Arvada, CO
> www.conniechristensen.com
>
>
____________________________________________________________________
___
> _______
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your
subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
> melpots@pclink.com.
>
>
www.murrow.biz/hank
____________________________________________________________________
__________
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.
Roger Korn on thu 3 feb 05
Wayne wrote:
Hank and all:
An interesting thought just occurred...
Has anyone built a "standard" kiln with TWO chambers, the one to the
rear (closest to the stack) for soda or salt, and the one in the
"front" for regular firing? Would that keep the front chamber
"uncontaminated"? Perhaps even with it's own burners for each
chamber?=20
Would this even work? Excuse me if this is a stupid question,
I just don't have the experience yet to know.
(By standard, I mean along the lines of an MFT, or any "square"
style "western" variety kiln)
I keep looking at the multiple chambered kilns, wondering why.
Wayne Seidl
Paul Herman fires an anagama with an arch chamber between the anagama
and the flue. He uses this chamber for salt. Seems to work well.
Roger
--
McKay Creek Ceramics
In OR: PO Box 436
North Plains, OR 97133
503-647-5464
In AZ: PO Box 463
Rimrock, AZ 86335
928-567-5699
Christine Martin on thu 3 feb 05
----- Original Message -----
From: "Hank Murrow"
To:
Sent: Wednesday, February 02, 2005 8:06 PM
Subject: Re: Using gas reduction kiln for soda firing
> On Feb 2, 2005, at 3:23 PM, wjskw@BELLSOUTH.NET wrote:
>
>> Hank and all:
>> An interesting thought just occurred...
>> Has anyone built a "standard" kiln with TWO chambers, the one to the
>> rear (closest to the stack) for soda or salt, and the one in the
>> "front" for regular firing? Would that keep the front chamber
>> "uncontaminated"? Perhaps even with it's own burners for each
>> chamber?
> Dear Wayne;
>
> Of course one could build such a two-chamber (or more) kiln such as you
> Cheers, Hank> describe. The problem would come in having to fire both in
> order to
> fire one. Most potters build kilns which are too large for timely
> feedback.
>
> www.murrow.biz/hank
>
> ______________________________________________________________________________
> 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.
Ken Nowicki on thu 3 feb 05
Wayne... I for one... don't think that this line of thinking is "stupid" at
all! In my mind anyway... it's EXACTLY this kind of thinking that keeps
moving our profession forward to new heights and innovations!
I haven't heard of such a design before, or know of one... but it certainly
is worthy of future investigation and research... go for it dude!!!
- Ken
Kenneth J. Nowicki
Port Washington, NY
RakuArtist@aol.com
Charter Member/Potters Council
Wayne wrote:
................................................................
Hank and all:
An interesting thought just occurred...
Has anyone built a "standard" kiln with TWO chambers, the one to the
rear (closest to the stack) for soda or salt, and the one in the
"front" for regular firing? Would that keep the front chamber
"uncontaminated"? Perhaps even with it's own burners for each
chamber?
Would this even work? Excuse me if this is a stupid question,
I just don't have the experience yet to know.
(By standard, I mean along the lines of an MFT, or any "square"
style "western" variety kiln)
I keep looking at the multiple chambered kilns, wondering why.
Wayne Seidl
................................................................
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