search  current discussion  categories  kilns & firing - salt & soda 

soda kiln

updated tue 24 apr 12

 

Don Curtis on sun 12 jul 98

We're building a propane fired catenary arch soda kiln about 20 cu ft. out of
hard firebricks. In Ruthane Tudball's Book "Soda Glazing" she reviews a kiln
built by Jack Doherty in which he uses two burners mounted on either side of
the kiln one in the front and the other mounted in the rear. Does anyone have
experience with this burner arrangement. Also looking for low cost ideas for a
material to cover the outside of the kiln with to improve its insulation and
if possible to waterproof it. Finally we're considering using ITC 100 as all
interior surfaces.
Any comments, personal experiences or suggestions would be greatly
appreciated.
Thanks in advance.

Don
In the beautiful pioneer valley of Western Massachusetts

Stephen Mills on mon 13 jul 98

My last production gas Kiln had burners in this arrangement. This was a
30 cu ft setting area (55 gross) mains gas car Kiln. The burners were
set up; one left hand back facing forward, and t'other RH front firing
back. It was absolutely even top to bottom, front to back.
It was a Fibre and Board Kiln built like a box wider than it was tall &
longer than it was wide. The flue exits from the chamber were three
slots in the truck floor; front, middle, & back. The middle one was half
the width of either of the others. When I moved out of the workshop and
out of production I sold the frame to another local potter and helped
them rebuild it. it's still going strong.

Steve
Bath
UK


In message , Don Curtis writes
>----------------------------Original message----------------------------
>We're building a propane fired catenary arch soda kiln about 20 cu ft. out of
>hard firebricks. In Ruthane Tudball's Book "Soda Glazing" she reviews a kiln
>built by Jack Doherty in which he uses two burners mounted on either side of
>the kiln one in the front and the other mounted in the rear. Does anyone have
>experience with this burner arrangement. Also looking for low cost ideas for a
>material to cover the outside of the kiln with to improve its insulation and
>if possible to waterproof it. Finally we're considering using ITC 100 as all
>interior surfaces.
>Any comments, personal experiences or suggestions would be greatly
>appreciated.
>Thanks in advance.
>
>Don
>In the beautiful pioneer valley of Western Massachusetts
>

--
Steve Mills
Bath
UK
home e-mail: stevemills@mudslinger.demon.co.uk
work e-mail: stevemills@bathpotters.demon.co.uk
own website: http://www.mudslinger.demon.co.uk
BPS website: http://www.bathpotters.demon.co.uk

Clyde Tullis on mon 13 jul 98

Don,
Burner arrangement - I've seen it work very well when on the same kiln, two from
the rear didn't. Just be sure you've got enough BTUs.
Sometimes you can find bunches of broken soft brick. These mudded together with
castable works great. Castable can be Fireclay, Sand or grog, coarse saw dust,
and Lumnite Cement. The Lumnite retains it's bond at higher temps. Soak the
soft brick before laying them up.

Clyde
In the Big Horned Sheep Canyon on the Arkansas River.



Don Curtis wrote:

> ----------------------------Original message----------------------------
> We're building a propane fired catenary arch soda kiln about 20 cu ft. out of
> hard firebricks. In Ruthane Tudball's Book "Soda Glazing" she reviews a kiln
> built by Jack Doherty in which he uses two burners mounted on either side of
> the kiln one in the front and the other mounted in the rear. Does anyone have
> experience with this burner arrangement. Also looking for low cost ideas for a
> material to cover the outside of the kiln with to improve its insulation and
> if possible to waterproof it. Finally we're considering using ITC 100 as all
> interior surfaces.
> Any comments, personal experiences or suggestions would be greatly
> appreciated.
> Thanks in advance.
>
> Don
> In the beautiful pioneer valley of Western Massachusetts

Gail Bakutis on tue 14 jul 98

I was just in England teaching at the Royal Forest of Dean College with
Jack Doherty. He was firing his soda kiln in preparation for a major
show in London at Contemporary Ceramics. His kiln is a hard brick,
downdraft, catenary arch kiln. The soda is mixed with water and pumped
through tiny pipes to spray (somewhat like a sprinkler system) into
specific holes in the kiln.

Don Curtis on thu 16 jul 98

Thanks for the replies to my questions about Soda kilns

Don

Rikki Gill on sat 8 jan 05


Is it more of a problem to fire a soda kiln than a gas reduction kiln in
terms of air quality? I fire a backyard kiln now, and have thought a soda
kiln might be interesting. I don't want to create problems with my
neighbors. I fire shino now, heavy reduction, but no complaints. Just
wondering.

Rikki Gill
www.rikkigillceramics.com

ASHPOTS@AOL.COM on sat 8 jan 05


Check out Bill Buckners site , he has a soda kiln in Atlanta near down town,,
great pots ,great guy

Mark

Vince Pitelka on sat 8 jan 05


> Is it more of a problem to fire a soda kiln than a gas reduction kiln in
> terms of air quality? I fire a backyard kiln now, and have thought a soda
> kiln might be interesting. I don't want to create problems with my
> neighbors. I fire shino now, heavy reduction, but no complaints. Just
> wondering.

Rikki -
Well, it is Berkeley, but that means more tolerance with some people, and
more meddling social conscience (usually a GOOD thing) with others. So, it
all depends on your neighbors. There is nothing toxic to humans in the
output of a soda kiln, but it will cause metal surfaces to corrode over
time. There are sound reasons for only building and firing salt, soda, and
wood kilns in fairly remote locations.

Then again, a soda kiln produces much less visible "cloud" than a salt kiln,
especially if you close the damper while injecting soda. If you gave the
kiln a tall stack, I doubt that anyone would even notice.

Speaking of which, one day in the mid-70s, when I was making pots in
Humboldt County, California, glassblower friend Ro Purser and I drove up to
visit mutual friend Mike Selfridge in Crescent City, CA (the only city in
the continental US in recorded history to have been hit by a Tsunami). Mike
was firing a new salt kiln, and we expected him to be salting about the time
we got there. As it turned out, he had already started salting. As Ro and
I drove down the grade approaching the south end of town, we descended into
a fogbank. That's not an unusual thing on the North Coast, but as we
zig-zagged through old residential areas northwest of downtown, approaching
Mike's place, we kept leaving and re-entering the fogbank. We circled north
of his place, and there was no fogbank. We checked, and there was a soft
breeze from the northwest. The entire fogbank was being seeded by the
output of Mike's salt kiln during salting. No harm done, but what a thing
to bea ble to do! I CAN CREATE A FOGBANK AT WILL!
MMMMMHOOOHOOOHOOHAAAAHAAAHAAAHAAA!!!!

I'm surprised this hasn't occured to anyone in the military. Recruit
salt-glaze potters and send them overseas to build and fire salt kilns,
producing fogbanks that would stop traffic in and out of enemy airfields.
Hmmm, maybe too low-tech. Perhaps a salt kiln with a digital readout panel
and computerized monitoring of 247 variables?

Needless to say, no one in Berkeley would notice the fog.
- 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/

Louis Katz on sun 9 jan 05


When it is 50-60 degrees here and very humid our soda kiln produces a
noticable cloud. Developing a drip system for the last few hours might
make sense if you are trying to keep the kiln a secret and not rock the
boat. We get our several gallons of water and couple of pounds of soda
into the kiln in a ten minute period.
Louis
On Jan 8, 2005, at 8:30 PM, Vince Pitelka wrote:

>> Is it more of a problem to fire a soda kiln than a gas reduction kiln
>> in
>> terms of air quality? I fire a backyard kiln now, and have thought a
>> soda
>> kiln might be interesting. I don't want to create problems with my
>> neighbors. I fire shino now, heavy reduction, but no complaints.
>> Just
>> wondering.
>
> Rikki -
> Well, it is Berkeley, but that means more tolerance with some people,
> and
> more meddling social conscience (usually a GOOD thing) with others.
> So, it
> all depends on your neighbors. There is nothing toxic to humans in the
> output of a soda kiln, but it will cause metal surfaces to corrode over
> time. There are sound reasons for only building and firing salt,
> soda, and
> wood kilns in fairly remote locations.
>
> Then again, a soda kiln produces much less visible "cloud" than a salt
> kiln,
> especially if you close the damper while injecting soda. If you gave
> the
> kiln a tall stack, I doubt that anyone would even notice.
>
> Speaking of which, one day in the mid-70s, when I was making pots in
> Humboldt County, California, glassblower friend Ro Purser and I drove
> up to
> visit mutual friend Mike Selfridge in Crescent City, CA (the only city
> in
> the continental US in recorded history to have been hit by a Tsunami).
> Mike
> was firing a new salt kiln, and we expected him to be salting about
> the time
> we got there. As it turned out, he had already started salting. As
> Ro and
> I drove down the grade approaching the south end of town, we descended
> into
> a fogbank. That's not an unusual thing on the North Coast, but as we
> zig-zagged through old residential areas northwest of downtown,
> approaching
> Mike's place, we kept leaving and re-entering the fogbank. We circled
> north
> of his place, and there was no fogbank. We checked, and there was a
> soft
> breeze from the northwest. The entire fogbank was being seeded by the
> output of Mike's salt kiln during salting. No harm done, but what a
> thing
> to bea ble to do! I CAN CREATE A FOGBANK AT WILL!
> MMMMMHOOOHOOOHOOHAAAAHAAAHAAAHAAA!!!!
>
> I'm surprised this hasn't occured to anyone in the military. Recruit
> salt-glaze potters and send them overseas to build and fire salt kilns,
> producing fogbanks that would stop traffic in and out of enemy
> airfields.
> Hmmm, maybe too low-tech. Perhaps a salt kiln with a digital readout
> panel
> and computerized monitoring of 247 variables?
>
> Needless to say, no one in Berkeley would notice the fog.
> - 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/
>
> _______________________________________________________________________
> _______
> 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.
>
>
Louis Katz

Question Questioning

ilene mahler on fri 7 apr 06


e-maIL me tomorrow we have one at Wesleyan Potters in Middletown Conn,and
its' first firing was this week and we empty tomorrow...Ilene
...imahler@comcast.com
i
----- Original Message -----
From: "dennis mclaughlin"
To:
Sent: Friday, April 07, 2006 5:17 PM
Subject: soda kiln


> Greetings,
>
> I'm gathering information on soda kilns, hoping to build one within the
> next year.
> Instead of "reinventing the wheel" I'm looking plans that have been
> used for a kiln with a sitting area using 12x24 shelves or close to that
> dimension.
> Specific questions I have are: Best brick to use as a liner?
> Best kiln shelves to use?
> Source of sprayers to use?
> Thanks again for a great site!
>
> Denny
>
>
>
>
>
> ---------------------------------
> Blab-away for as little as 1¢/min. Make PC-to-Phone Calls using Yahoo!
> Messenger with Voice.
>
> ______________________________________________________________________________
> 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.

dennis mclaughlin on fri 7 apr 06


Greetings,

I'm gathering information on soda kilns, hoping to build one within the next year.
Instead of "reinventing the wheel" I'm looking plans that have been used for a kiln with a sitting area using 12x24 shelves or close to that dimension.
Specific questions I have are: Best brick to use as a liner?
Best kiln shelves to use?
Source of sprayers to use?
Thanks again for a great site!

Denny





---------------------------------
Blab-away for as little as 1¢/min. Make PC-to-Phone Calls using Yahoo! Messenger with Voice.

Brian Crocker on sat 8 apr 06


May I suggest that you view a book ?

The Kiln Book, by Frederick Olsen . 738.13.

Kind regards,

Brian Crocker in South Aus.
======================== [;-)


----- Original Message -----
From: "dennis mclaughlin"
To:
Sent: Saturday, April 08, 2006 6:47 AM
Subject: soda kiln


Greetings,

I'm gathering information on soda kilns, hoping to build one within the
next year.
Instead of "reinventing the wheel" I'm looking plans that have been used
for a kiln with a sitting area using 12x24 shelves or close to that
dimension.
Specific questions I have are: Best brick to use as a liner?
Best kiln shelves to use?
Source of sprayers to use?
Thanks again for a great site!

Denny





---------------------------------
Blab-away for as little as 1¢/min. Make PC-to-Phone Calls using Yahoo!
Messenger with Voice.

______________________________________________________________________________
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.


--
No virus found in this incoming message.
Checked by AVG Free Edition.
Version: 7.1.385 / Virus Database: 268.3.5/303 - Release Date: 6/04/2006

BJ Clark | Stinking Desert Ceramics on sat 8 apr 06


Denny,
If your interested in Soda Firing, I suggest either Phil Rogers book "Salt
Glazing" or Rosemary Cochrane's book "Salt-Glazed Ceramics". Both have
plan's for many types of Soda kilns from small to large, gas to wood. If
you only buy one, I suggest Phil's book.

BJ Clark
Stinking Desert Ceramics
Colorado



On 4/7/06, dennis mclaughlin wrote:
>
> Greetings,
>
> I'm gathering information on soda kilns, hoping to build one within the
> next year.
> Instead of "reinventing the wheel" I'm looking plans that have been
> used for a kiln with a sitting area using 12x24 shelves or close to that
> dimension.
> Specific questions I have are: Best brick to use as a liner?
> Best kiln shelves to use?
> Source of sprayers to use?
> Thanks again for a great site!
>
> Denny
>
>
>
>
>
> ---------------------------------
> Blab-away for as little as 1=A2/min. Make PC-to-Phone Calls using Yahoo!
> Messenger with Voice.
>
>
> _________________________________________________________________________=
_____
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
> melpots@pclink.com.
>



--
BJ Clark
Stinking Desert Ceramics
bjclark@stinkingdesert.com
www.stinkingdesert.com

Dan Hill on sat 8 apr 06


Denny.
My soda kiln has about 60 firings on it with very little deterioration. I
built it out of salvaged hard fire brick from a friends woodkiln.The kiln
has 3" of Kawool blanket over the arch and insulating fire brick as backu=
p
on the ends. I used Mizzou castable in the flameway/soda trough and it al=
so
is standing up well.
It is a catenary arch of about 25 cu. ft. 3 rows of 12 X 24" shelves.
Silica carbide type shelves seem to hold up much better than standard cla=
y
shelves. Much less flaking and cracking.
I should say here that I fire to ^6 where most people fire to ^9 or ^10. =
I
think the lower firing temperature means much less deterioration of the k=
iln
and shelves.
I spray with a standard garden sprayer. Just make sure you get one with a
metal wand and that you can get replacement ends for it.
This kiln fires great and was built very for very little $ but the firing
costs are much to high because of the hardbrick. If I had to do it again =
I
would build with ifbs dipped in either ITC or something similar for the h=
ot
face of the kiln.
Dan Hill
Wilno, Ont. Canada
----- Original Message -----
From: "dennis mclaughlin"
To:
Sent: Friday, April 07, 2006 5:17 PM
Subject: soda kiln


> Greetings,
>
> I'm gathering information on soda kilns, hoping to build one within t=
he
next year.
> Instead of "reinventing the wheel" I'm looking plans that have been
used for a kiln with a sitting area using 12x24 shelves or close to that
dimension.
> Specific questions I have are: Best brick to use as a liner?
> Best kiln shelves to use?
> Source of sprayers to use?
> Thanks again for a great site!
>
> Denny
>
>
>
>
>
> ---------------------------------
> Blab-away for as little as 1=A2/min. Make PC-to-Phone Calls using Yaho=
o!
Messenger with Voice.
>
>
_________________________________________________________________________=
___
__
> 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.
>
>

Kendra Bogert on tue 6 jul 10


Hi, Clayart. I have a question for soda kiln people.
I'm at a university firing a soda kiln, the last two firings haven't
gone well. They both lasted around 30 hours each, but the 7 or so
firings before these two were around 24.
The kiln fits 2 12 x 24 shelves side by side, and we're using pine and oak.
The kiln climbs evenly until around cone 7, (which has been around 5:00
in the afternoon for both of these firings) and the cones hardly move
until the sun goes down around 8:30, and the last firing we got cone 11
to bend slightly and shut down around midnight after spraying soda.
(We're using 1/2 gallon of water to 1 1/2 pounds of soda.)
Is there any way that the summer weather has affected these two firings?

Dana & Chris Trabka on wed 7 jul 10


Kendra,

I had a similar experience with my gas fired kiln. It was a hot sultry
afternoon. I fired as usual (which normally ends about 9:00pm). It was now
9:00 and cone 6 hadn't moved!!! I finally finished at 3:00am. I checked and
double checked my log books. I followed the normal schedule for gas and
damper settings. I needed more information. I ordered an oxyprobe. The next
few firings were eye-openers. When it is crisp and dry I can use 3-inches o=
f
water column pressure. When it is hot and muggy I dare not exceed 2.5-inche=
s
of water column pressure. When it is muggy, the water suspended in the
atmosphere displaces the oxygen (and nitrogen). This means that there is no=
t
as much oxygen in the air. Thus you need to use less fuel to get similar
results (or open the damper).

Chris
----- Original Message -----
From: "Kendra Bogert"
To:
Sent: Tuesday, July 06, 2010 11:23 PM
Subject: Soda Kiln


> Hi, Clayart. I have a question for soda kiln people.
> I'm at a university firing a soda kiln, the last two firings haven't
> gone well. They both lasted around 30 hours each, but the 7 or so
> firings before these two were around 24.
> The kiln fits 2 12 x 24 shelves side by side, and we're using pine and
> oak.
> The kiln climbs evenly until around cone 7, (which has been around 5:00
> in the afternoon for both of these firings) and the cones hardly move
> until the sun goes down around 8:30, and the last firing we got cone 11
> to bend slightly and shut down around midnight after spraying soda.
> (We're using 1/2 gallon of water to 1 1/2 pounds of soda.)
> Is there any way that the summer weather has affected these two firings?

David Hendley on wed 7 jul 10


I assume from the "pine and oak" reference that this is a
wood-fired kiln?
The first, most likely, and easiest to remedy problem
with a wood kiln is the wood supply. Changes in the
characteristics of the wood are way more important then
changes in the weather,

A little kiln of this size should be able to reach cone 10
in well under 12 hours, even with reduction and adding the
soda and taking things nice and slow.
If you are having trouble, make sure your wood is truly
and completely dry. Split it into smaller-sized pieces, weeks
before the firing, and sticker them to dry. In the summer,
a few weeks in the sun, with a handy tarp cover in case of
rain should do it.

I am not a "soda kiln person", but have fired with wood for
20 years.
David Hendley
david@farmpots.com
http://www.farmpots.com


----- Original Message -----
> Hi, Clayart. I have a question for soda kiln people.
> I'm at a university firing a soda kiln, the last two firings haven't
> gone well. They both lasted around 30 hours each, but the 7 or so
> firings before these two were around 24.
> The kiln fits 2 12 x 24 shelves side by side, and we're using pine and
> oak.
> The kiln climbs evenly until around cone 7, (which has been around 5:00
> in the afternoon for both of these firings) and the cones hardly move
> until the sun goes down around 8:30, and the last firing we got cone 11
> to bend slightly and shut down around midnight after spraying soda.
> (We're using 1/2 gallon of water to 1 1/2 pounds of soda.)
> Is there any way that the summer weather has affected these two firings?

ivor and olive lewis on thu 8 jul 10


Dear Kendra Bogert,

Sounds as though your kiln is stalling. There are many reasons why this
might happen and it could be nothing to do with local atmospheric
conditions.

You say nothing about damper settings, frequency of stoking,

Do you have a tall chimney or is it squat ?

I have always found that with my gas firings I get a better results in wet
or damp weather. But I have to be aware of what the kiln is doing and make
adjustments accordingly.

IF water is being introduced into a wood fuelled kiln, the superheated stea=
m
can be react with your incandescent coals, generating Free Hydrogen and
Carbon Monoxide. If there is insufficient draught to provide oxygen to
ensure these gases burn your fire will tend to cool down rather than advanc=
e
to its maturity temperature.



Best regards,

Ivor Lewis,
REDHILL,
South Australia

Lee Love on thu 8 jul 10


On Wed, Jul 7, 2010 at 3:31 PM, David Hendley wrote:
> I assume from the "pine and oak" reference that this is a
> wood-fired kiln?
> The first, most likely, and easiest to remedy problem
> with a wood kiln is the wood supply.

Equally important to the wood is the stokers. In a group
situation, you need a captain. The most frequent mistake
inexperienced stokers commit is over stoking.

--
Lee, a Mashiko potter in Minneapolis
http://mingeisota.blogspot.com/

=3D93Observe the wonders as they occur around you. Don't claim them. Feel
the artistry moving through and be silent.=3D94 --Rumi

Ilene Mahler on sun 19 sep 10


I am on a mission...Is there such a thing as a converted soda kiln base =3D
is an old electris...if so can some one e-mail me the plans...I am doing =
=3D
well 2 months after revision surgery in my right knee I am driving =3D
etc..was going to the studio this weekend to see if I can bend my knee =3D
enough to throw didn't guess I'm chicken...Ilene in Conn

Ben Morrison on wed 18 apr 12


One thing I will say is that you will want to dedicate the kiln =3D

Eric,=3D0A=3D0AOne thing I will say is that you will want to dedicate the k=
iln =3D
to soda. The soda soaks into the bricks. Depending on the kind of brick you=
=3D
use K-23 soft brick, or hard brick you'll get different life out of the br=
=3D
icks, =3D0Aand a different rate of absorption. The absorbed salt or soda ga=
ss=3D
es off =3D0Aduring the firing and will foul some glazes like Shino for inst=
an=3D
ce. If =3D0Ayou do a lot of copper glazing the soda soaked bricks can quick=
ly=3D
absorb the copper and when the bricks gas off it can blush the pots in the=
=3D
=3D0Akiln much more so than a normal high fire kiln will. I've been told t=
he=3D
same thing happens with chrome. I =3D0Afired a soda kiln at the college th=
at=3D
had been used to fire a whole load of =3D0Acopper turquoise pots before th=
e =3D
hard bricks were sufficiently coated with glass. The copper soaked into the=
=3D
bricks and the next dozen loads I saw come out of that kiln came out with =
=3D
a pink or green blush on the =3D0Aside. I just quit firing in it altogether=
. =3D
previously bisqued slips like a blue engobe don't seem to have such a =3D0A=
dr=3D
astic gas off effect. Especially after there is a good coat of glass =3D0Ao=
n =3D
the bricks.=3D0A=3D0AYou'll want to thoroughly investigate the materials yo=
u us=3D
e in your soda=3D0A kiln because conventional wisdom can lead you astray. R=
es=3D
isting the =3D0Asoda with alumina is really not a tactic that I've found pa=
ys=3D
off in the=3D0A end. An article I read states that K-23 bricks actually ho=
ld=3D
up =3D0Abetter than K-26. This seems counter intuitive until you realize t=
ha=3D
t =3D0Aalumina and soda are apposing forces in the heat of a kiln. The high=
er=3D
=3D0Aalumina content in a brick the more it tries to resist the relentless=
f=3D
orces of salt and soda. Soda =3D0Amixed with calcium like the Gail Nichols =
me=3D
thod will eat expensive =3D0Abubble alumina bricks for breakfast if left na=
ke=3D
d and uncoated. One way I've seen to protect insulating bricks that seems c=
=3D
ost effective and altogether smart is laying up 2" thick castable cement wa=
=3D
lls on the inside of a soft brick kiln made of K-23's. This sacrificial lay=
=3D
er will stand up to some serious abuse before it fails and needs to be redo=
=3D
ne. It's fairly inexpensive to redo, though it is a bit labor intensive. Th=
=3D
e nice thing about castable or rammable cement is that they can be chemical=
=3D
ly enhanced in the mix to better suit your needs.=3D0A=3D0AThin Chinese SiC=
She=3D
lving works best (not advancer) and don't coat them with a kiln shelf wash,=
=3D
they resist the soda chemically on their own. All they =3D0Aneed is a ligh=
t =3D
scrape to clean off the very thin foam bubbles =3D0Athat form.=3D0A=3D0AHer=
e's so=3D
me more information that may help you on your endeavor. The first article b=
=3D
elow is probably one of the most helpful things I've found about materials =
=3D
for building a salt/soda kiln. The second link is to a kiln project which h=
=3D
as some very interesting results. I would stay away from thermal blanket th=
=3D
ough as it gets destroyed very quickly. The slip recipes on that site are a=
=3D
wesome though.=3D0A=3D0A=3D0Ahttp://kilnshelf.com/Websites/kilnshelf/Images=
/Insul=3D
ating%20Materials%20for%20Salt%20Kilns%20Article.pdf=3D0A=3D0Ahttp://kazega=
ma.c=3D
om/soda.htm=3D0A=3D0A=3D0ABest of luck,=3D0A=3D0ABen=3D0A=3D0A=3D0A=3D0A=3D=
0A__________________=3D
______________=3D0A From: Eric Newman =3D0ATo: C=
laya=3D
rt@LSV.CERAMICS.ORG =3D0ASent: Wednesday, April 18, 2012 10:53 AM=3D0ASubje=
ct: =3D
Soda Kiln=3D0A =3D0AOur studio is considering building a new gas kiln to be=
use=3D
d, hopefully, for both =3D0Asoda firings and regular Cone 10 reduction firi=
ng=3D
s.=3DA0 Can anyone confirm that a) the =3D0ACone 10 firings won't be affect=
ed b=3D
y occasional soda firings; and b) if separate =3D0Ashelving will be necessa=
ry=3D
.=3DA0 Everything I have read says that kilns and shelves =3D0Aneed to be d=
edic=3D
ated to one or the other, but some anecdotal evidence states =3D0Athat comb=
in=3D
ation usage ain't so bad.=3DA0 Anyone out there have experience to share?

Hank Murrow on wed 18 apr 12


On Apr 18, 2012, at 10:53 AM, Eric Newman wrote:

> Our studio is considering building a new gas kiln to be used, =3D
hopefully, for both=3D20
> soda firings and regular Cone 10 reduction firings. Can anyone =3D
confirm that a) the=3D20
> Cone 10 firings won't be affected by occasional soda firings; and b) =3D
if separate=3D20
> shelving will be necessary. Everything I have read says that kilns =3D
and shelves=3D20
> need to be dedicated to one or the other, but some anecdotal evidence =3D
states=3D20
> that combination usage ain't so bad. Anyone out there have experience =
=3D
to share?

Yes, I believe I can help from the experience I have had. Everything =3D
depends upon how local you can keep the soda/salt in the kiln during the =
=3D
liquid phase. The main problem with vapor glazing comes during the =3D
liquid phase after you throw the salt/soda into the firebox. The liquid =3D
soda/salt melts into the cracks/joints in the brickwork and solidifies =3D
again, spreading the bricks a bit. During the next firing it melts and =3D
more runs into the cracks, cooling and spreading the bricks some more.

I have had great success with salt 'pans'; castable pans that line the =3D
firebox and have 1" high lips around their periphery to contain the =3D
molten salt/soda. These and the kiln itself can be painted with aluminum =
=3D
paint(hardware/paint store) to provide a nice alumina oxide =3D
surface(after the volatiles burn off) for the next firing. I use ceramic =
=3D
fiber gaskets to separate the pans from the walls of the firebox so they =
=3D
can be removed for eventual replacement, as needed.

I have also had great luck with casting panels for use as wall sections =3D
and roof sections that are backed up with fiber or block insulation. it =3D
is possible in this way to build a relatively light weight kiln that =3D
resists salt/soda while not requiring the fuel that a brick kiln needs =3D
to heat the mass of brick. Say, 1" thick castable panels with 6" of =3D
backup fiber in two layers, the fits layer somewhat expensive, and the =3D
second not so.

I have fired natural draft with heating oil(stove oil) very successfully =
=3D
and with both propane and natural gas as well. At present, I am =3D
designing a 10 cuft kiln that can fire alternate loads of =3D
soda/salt/stoneware/porcelain with little to no deleterious effects from =
=3D
one fire to the next. Time will prove or disprove the efficacy of the =3D
design. I'm excited about the prospect of this new designturning out to =3D
be a '3 in 1' fuel kiln that would be practical for those wanting to =3D
move beyond electric firing.

Cheers, Hank=3D

Eric Newman on wed 18 apr 12


Our studio is considering building a new gas kiln to be used, hopefully, =
=3D
for both=3D20
soda firings and regular Cone 10 reduction firings. Can anyone confirm t=
=3D
hat a) the=3D20
Cone 10 firings won't be affected by occasional soda firings; and b) if s=
=3D
eparate=3D20
shelving will be necessary. Everything I have read says that kilns and s=
=3D
helves=3D20
need to be dedicated to one or the other, but some anecdotal evidence sta=
=3D
tes=3D20
that combination usage ain't so bad. Anyone out there have experience to=
=3D
share?

Steve Mills on thu 19 apr 12


I'm afraid you will find that once a Kiln has been used for Vapour Glazing,=
t=3D
hat "contamination" will influence the outcome of all subsequent firings re=
g=3D
ardless of type!

Steve M


Steve Mills
Bath
UK
www.mudslinger.me.uk
Sent from my iPod


On 18 Apr 2012, at 18:53, Eric Newman wrote:

> Our studio is considering building a new gas kiln to be used, hopefully, =
f=3D
or both=3D20
> soda firings and regular Cone 10 reduction firings. Can anyone confirm t=
h=3D
at a) the=3D20
> Cone 10 firings won't be affected by occasional soda firings; and b) if s=
e=3D
parate=3D20
> shelving will be necessary. Everything I have read says that kilns and s=
h=3D
elves=3D20
> need to be dedicated to one or the other, but some anecdotal evidence sta=
t=3D
es=3D20
> that combination usage ain't so bad. Anyone out there have experience to=
s=3D
hare?

Hank Murrow on sat 21 apr 12


On Apr 21, 2012, at 5:55 PM, Vince Pitelka wrote:

> Soda firing is far less corrosive and intrusive than salt firing. =3D
Residual
> salt firings are common, relying on re-volatilization of the salt =3D
impacted
> in the refractory without charging any additional salt. No one does =3D
that
> with soda kilns because the residual effects are so minimal. So, while =
=3D
you
> could not have a truly multi-purpose kiln used partially for soda, you =
=3D
could
> do firings without charging any soda and the atmospheric effects would =
=3D
be
> minimal. You could fire the kiln with reduction glazes and have a very
> minimal soda effect. We have never done that with our soda kiln, but =3D
I have
> always wondered about the effect.

Providing there is no unmelted/vaporised salt/soda in the refractories; =3D
it is quite possible to fire a normal glaze firing after wards. One just =
=3D
has to cast panels with minimal to no porosity. I do this by making =3D
molds that are glassy-finished and vibrate the castable in place. It =3D
also needs to be a castable with salt resistance like Flocast 30S, which =
=3D
contains 12% SiC. There are others, but Flocast 30S is pretty reasonable =
=3D
@ $70/cwt.

The floor panels I cast are in removable sections with fiber 'gaskets' =3D
between to facillitate removal when needed.

Cheers, Hank=3D

douglas fur on sat 21 apr 12


Hank
These are rhetorical questions to further the discussion-.
We all have had the experience of "one tool that does it all" which in the
end we find "does all" in a halfassed way. (excepting, maybe, Leatherman
and Shopsmith and a few others)

How does one design a multi-purpose kiln? Do you put in larger flame-ways
to dispurse vapors or larger fireboxes which are functional for vapor
firing but are excess baggage for a regular fire?. On the other hand do you
find, from your experience, that such design assumptions of "common wisdom"
are only assumptions not not based in facts?

DRB
Seola Creek.

Hank Murrow on sat 21 apr 12


On Apr 21, 2012, at 11:27 AM, douglas fur wrote:

> Hank
> These are rhetorical questions to further the discussion-.
> We all have had the experience of "one tool that does it all" which in =
=3D
the end we find "does all" in a halfassed way. (excepting, maybe, =3D
Leatherman and Shopsmith and a few others)
> =3D20
> How does one design a multi-purpose kiln? Do you put in larger =3D
flame-ways to dispurse vapors or larger fireboxes which are functional =3D
for vapor firing but are excess baggage for a regular fire?. On the =3D
other hand do you find, from your experience, that such design =3D
assumptions of "common wisdom" are only assumptions not not based in =3D
facts?
> =3D20

Well, my experience taught me that the main problem of multi-use kilns =3D
is soda/salt retention in the refractories after the firing. This =3D
residual soda/salt disrupts the normal melt in a subsequent glaze firing =
=3D
enough to make such usage impractical.

Additionally, the molten salt/soda tends to get into the joints of the =3D
brickwork where it hardens during cooling and waits until the next =3D
firing to melt again. As it 'freezes', it expands, pushing the bricks =3D
apart, and ultimately rendering the kiln useless.

My solution to both problems is to fabricate the interior of the kiln =3D
with salt/soda-resistant castable panels with a very thin cross-section =3D
allowing several inches of fiber for backup insulation to minimize heat =3D
storage and promote fuel efficiency. I have cast panels as little as =3D
3/4" in thickness from very salt/soda resistant castables so that the =3D
castable forms a tough barrier with minimal joints. In addition, I cast =3D
a trough into the floor panels that confines the molten salt to a small =3D
space in the firebox, from which it turns to vapor, glazes the pots, and =
=3D
is pretty much used up before leaving the kiln. The result is a kiln =3D
that can be used for all three types of firing interchangeably, with =3D
little compromise. At 10_12 cuft stacking on pairs of 12" x 24"shelves, =3D
it seems an ideal step up from electric firing for a small studio, =3D
especially if the potter is curious about the behavior of ceramic =3D
materials in different conditions of melt, and different cooling =3D
profiles. Like my Doorless design, such a kiln could fire nearly any =3D
conceivable firing profile, depending only upon the question at hand. I =3D
have fired reduction and oxidation fires from ten hours to forty hours =3D
with or without additional soaks during the cooling, for instance.

Anyway, that is my current thinking. I may or may not get to try a solar =
=3D
kiln in my lifetime. Do have a plan in case I find the time though!

Cheers, Hank

Vince Pitelka on sat 21 apr 12


Soda firing is far less corrosive and intrusive than salt firing. Residual
salt firings are common, relying on re-volatilization of the salt impacted
in the refractory without charging any additional salt. No one does that
with soda kilns because the residual effects are so minimal. So, while you
could not have a truly multi-purpose kiln used partially for soda, you coul=
d
do firings without charging any soda and the atmospheric effects would be
minimal. You could fire the kiln with reduction glazes and have a very
minimal soda effect. We have never done that with our soda kiln, but I hav=
e
always wondered about the effect.
- Vince

Vince Pitelka
Appalachian Center for Craft
Tennessee Tech University
vpitelka@dtccom.net
http://iweb.tntech.edu/wpitelka/

brandon2@SUPPORTYOURLOCALPOTTER.COM on sun 22 apr 12


I personally don't ever soda fire, I prefer salt. Some of my students
however, will spray the soda in every damn opening of the kiln when they
fire it. I tell them not to spray the shelves directly but I'm sure it
happens. I'm often not around when they fire that kiln, finishing in the
middle of the night. But even when it's a light soda firing I notice
corrosion after they've been ground, wish I could post a photo here. It
almost looks like the soda eats away at the finest particles and leaves
the coarse...sort of like wiping down gritty clay and exposing the grog.
I don't see at as a significant threat to the shelves but I think would
certainly shorten the life over salt firing. I'm no expert in the matter,
just my observation.

Brandon Phillips

> I did not find this to be the case in our soda kiln, however we aren't
> spraying the shelves directly, but spraying a hot bag wall in a
> directional kiln which blasts the pots with fumes. Were you hitting the
> shelves directly with a soda blast?
>
> -Ben
>
>
>
> From: Vince Pitelka
> To: Clayart@LSV.CERAMICS.ORG
> Sent: Sunday, April 22, 2012 4:49 AM
> Subject: Re: Soda Kiln
>
> Brandon Phillips wrote:
> "In my experience(take it for what it's worth) in our crossdraft I have
> found salt to be by far the most corrosive around the firebox area, the
> soda can be more corrosive in localized areas(like spraying it on a
> wall.)=C2 As far as kiln shelves go we use=C2 3/4" SiC shelves and the =
soda is
> far more corrosive to the shelves than the salt is.=C2 Not sure why but =
it
> seems to corrode the shelves vs the salt just beading up on the surface.=
=C2
> This is in a university setting so again, take it for what it's worth."
>
> Hi Brandon -
> I agree about the effect of salt versus soda on the shelves.=C2 We use t=
he
> Chinese nitride-bonded sil-car shelves in both salt and soda, and they do
> seem to degrade faster in soda.=C2 In my experience, soda is less invasi=
ve,
> both in terms of its effect on the refractory and its effect on the
> wares.=C2 When you say that soda is more corrosive in localized areas, I
> think that is only because we CAN spray it on the wall or directly on the
> wares.=C2 We don't do that with salt.=C2 I like soda specifically it is=
less
> aggressive in its effect on the wares.=C2
>
> We have had students new to soda who simply didn't charge nearly enough
> sodium carbonate solution and got very dry surfaces, far dryer than you
> get in a residual salt firing in a well-seasoned salt kiln where no salt
> is charged during the firing.=C2 I have never run a "residual" soda firi=
ng,
> but have heard from others who have tried it and got almost no soda
> deposition on the wares - really just the slightest evidence, primarily
> visible in the contrast with areas where wadding is touching the wares.=
=C2
> There just does not seem to be much volatilization of the soda that has
> deposited on the refractory or accumulated in the firebox from previous
> firings.=C2 That corresponds with the fact that soda volatilizes best wh=
en
> sprayed into the kiln as a saturated soda ash solution.=C2 I know that s=
ome
> people charge with burritos of moistened soda ash mixed with calcium
> carbonate and other things, but I find that much harder on the kiln and w=
e
> try to stay away from
> that.=C2 We get such great results in our cross-draft soda kiln at
> temperatures from cone-1 to cone-11.=C2 One of my BFA students, Ellen
> Kleckner, has her senior thesis show up right now and it is all cone-1
> soda-fired terracotta using colored terra sigillatas and only small
> details of glaze here and there.=C2 She is getting such luscious surface=
s.=C2
> She is going places.=C2
> - Vince
>
> Vince Pitelka
> Appalachian Center for Craft
> Tennessee Tech University
> vpitelka@dtccom.net
> http://iweb.tntech.edu/wpitelka/
>

brandon2@SUPPORTYOURLOCALPOTTER.COM on sun 22 apr 12


In my experience(take it for what it's worth) in our crossdraft I have
found salt to be by far the most corrosive around the firebox area, the
soda can be more corrosive in localized areas(like spraying it on a wall.)
As far as kiln shelves go we use 3/4" SiC shelves and the soda is far
more corrosive to the shelves than the salt is. Not sure why but it seems
to corrode the shelves vs the salt just beading up on the surface. This
is in a university setting so again, take it for what it's worth.

Brandon Phillips


> Soda firing is far less corrosive and intrusive than salt firing.
> Residual
> salt firings are common, relying on re-volatilization of the salt impacte=
d
> in the refractory without charging any additional salt. No one does that
> with soda kilns because the residual effects are so minimal. So, while yo=
u
> could not have a truly multi-purpose kiln used partially for soda, you
> could
> do firings without charging any soda and the atmospheric effects would be
> minimal. You could fire the kiln with reduction glazes and have a very
> minimal soda effect. We have never done that with our soda kiln, but I
> have
> always wondered about the effect.
> - Vince
>
> Vince Pitelka
> Appalachian Center for Craft
> Tennessee Tech University
> vpitelka@dtccom.net
> http://iweb.tntech.edu/wpitelka/
>

Vince Pitelka on sun 22 apr 12


Brandon Phillips wrote:=3D20
"In my experience(take it for what it's worth) in our crossdraft I have =3D
found salt to be by far the most corrosive around the firebox area, the =3D
soda can be more corrosive in localized areas(like spraying it on a =3D
wall.) As far as kiln shelves go we use 3/4" SiC shelves and the soda =3D
is far more corrosive to the shelves than the salt is. Not sure why but =
=3D
it seems to corrode the shelves vs the salt just beading up on the =3D
surface. This is in a university setting so again, take it for what =3D
it's worth."

Hi Brandon -=3D20
I agree about the effect of salt versus soda on the shelves. We use the =
=3D
Chinese nitride-bonded sil-car shelves in both salt and soda, and they =3D
do seem to degrade faster in soda. In my experience, soda is less =3D
invasive, both in terms of its effect on the refractory and its effect =3D
on the wares. When you say that soda is more corrosive in localized =3D
areas, I think that is only because we CAN spray it on the wall or =3D
directly on the wares. We don't do that with salt. I like soda =3D
specifically it is less aggressive in its effect on the wares. =3D20

We have had students new to soda who simply didn't charge nearly enough =3D
sodium carbonate solution and got very dry surfaces, far dryer than you =3D
get in a residual salt firing in a well-seasoned salt kiln where no salt =
=3D
is charged during the firing. I have never run a "residual" soda =3D
firing, but have heard from others who have tried it and got almost no =3D
soda deposition on the wares - really just the slightest evidence, =3D
primarily visible in the contrast with areas where wadding is touching =3D
the wares. There just does not seem to be much volatilization of the =3D
soda that has deposited on the refractory or accumulated in the firebox =3D
from previous firings. That corresponds with the fact that soda =3D
volatilizes best when sprayed into the kiln as a saturated soda ash =3D
solution. I know that some people charge with burritos of moistened =3D
soda ash mixed with calcium carbonate and other things, but I find that =3D
much harder on the kiln and we try to stay away from that. We get such =3D
great results in our cross-draft soda kiln at temperatures from cone-1 =3D
to cone-11. One of my BFA students, Ellen Kleckner, has her senior =3D
thesis show up right now and it is all cone-1 soda-fired terracotta =3D
using colored terra sigillatas and only small details of glaze here and =3D
there. She is getting such luscious surfaces. She is going places. =3D20
- Vince

Vince Pitelka
Appalachian Center for Craft
Tennessee Tech University
vpitelka@dtccom.net
http://iweb.tntech.edu/wpitelka/

Steve Mills on sun 22 apr 12


Interestingly, Donald Shelley in the late '70s. patented a design using r=
e=3D
fractory tiles mounted on refractory posts fitted to the wall of a kiln wit=
h=3D
a fibre fill behind. There is an abstract of his patents on the F P O webs=
i=3D
te. There are associated PDFs as well, but I was unable to access them as I=
h=3D
ave a problem with the Reader program on my computer.=3D20
My second production kiln was designed by an associate of Shelley's, so I g=
o=3D
t to examine his system in detail.=3D20
It was very efficient.=3D20

Steve M



Steve Mills
Bath
UK
www.mudslinger.me.uk
Sent from my iPod


On 21 Apr 2012, at 20:45, Hank Murrow wrote:

> On Apr 21, 2012, at 11:27 AM, douglas fur wrote:
>=3D20
>> Hank
>> These are rhetorical questions to further the discussion-.
>> We all have had the experience of "one tool that does it all" which in t=
h=3D
e end we find "does all" in a halfassed way. (excepting, maybe, Leatherma=
n=3D
and Shopsmith and a few others)
>>=3D20
>> How does one design a multi-purpose kiln? Do you put in larger flame-way=
s=3D
to dispurse vapors or larger fireboxes which are functional for vapor firi=
n=3D
g but are excess baggage for a regular fire?. On the other hand do you find=
,=3D
from your experience, that such design assumptions of "common wisdom" are =
o=3D
nly assumptions not not based in facts?
>>=3D20
>=3D20
> Well, my experience taught me that the main problem of multi-use kilns is=
s=3D
oda/salt retention in the refractories after the firing. This residual soda=
/=3D
salt disrupts the normal melt in a subsequent glaze firing enough to make s=
u=3D
ch usage impractical.
>=3D20
> Additionally, the molten salt/soda tends to get into the joints of the br=
i=3D
ckwork where it hardens during cooling and waits until the next firing to m=
e=3D
lt again. As it 'freezes', it expands, pushing the bricks apart, and ultima=
t=3D
ely rendering the kiln useless.
>=3D20
> My solution to both problems is to fabricate the interior of the kiln wit=
h=3D
salt/soda-resistant castable panels with a very thin cross-section allowin=
g=3D
several inches of fiber for backup insulation to minimize heat storage and=
p=3D
romote fuel efficiency. I have cast panels as little as 3/4" in thickness f=
r=3D
om very salt/soda resistant castables so that the castable forms a tough ba=
r=3D
rier with minimal joints. In addition, I cast a trough into the floor panel=
s=3D
that confines the molten salt to a small space in the firebox, from which =
i=3D
t turns to vapor, glazes the pots, and is pretty much used up before leavin=
g=3D
the kiln. The result is a kiln that can be used for all three types of fir=
i=3D
ng interchangeably, with little compromise. At 10_12 cuft stacking on pairs=
o=3D
f 12" x 24"shelves, it seems an ideal step up from electric firing for a sm=
a=3D
ll studio, especially if the potter is curious about the behavior of cerami=
c=3D
materials in different conditions of melt, and different cooling profiles.=
L=3D
ike my Doorless design, such a kiln could fire nearly any conceivable firin=
g=3D
profile, depending only upon the question at hand. I have fired reduction =
a=3D
nd oxidation fires from ten hours to forty hours with or without additional=
s=3D
oaks during the cooling, for instance.
>=3D20
> Anyway, that is my current thinking. I may or may not get to try a solar =
k=3D
iln in my lifetime. Do have a plan in case I find the time though!
>=3D20
> Cheers, Hank

Ben Morrison on sun 22 apr 12


I did not find this to be the case in our soda kiln, however we aren't spra=
=3D
ying the shelves directly, but spraying a hot bag wall in a directional kil=
=3D
n which blasts the pots with fumes. Were you hitting the shelves directly w=
=3D
ith a soda blast?=3D0A=3D0A-Ben=3D0A=3D0A=3D0A=3D0AFrom: Vince Pitelka telka@DTCCOM=3D
.NET>=3D0ATo: Clayart@LSV.CERAMICS.ORG =3D0ASent: Sunday, April 22, 2012 4:=
49 A=3D
M=3D0ASubject: Re: Soda Kiln=3D0A =3D0ABrandon Phillips wrote: =3D0A"In my =
experien=3D
ce(take it for what it's worth) in our crossdraft I have found salt to be b=
=3D
y far the most corrosive around the firebox area, the soda can be more corr=
=3D
osive in localized areas(like spraying it on a wall.)=3DA0 As far as kiln s=
he=3D
lves go we use=3DA0 3/4" SiC shelves and the soda is far more corrosive to =
th=3D
e shelves than the salt is.=3DA0 Not sure why but it seems to corrode the s=
he=3D
lves vs the salt just beading up on the surface.=3DA0 This is in a universi=
ty=3D
setting so again, take it for what it's worth."=3D0A=3D0AHi Brandon - =3D0=
AI agr=3D
ee about the effect of salt versus soda on the shelves.=3DA0 We use the Chi=
ne=3D
se nitride-bonded sil-car shelves in both salt and soda, and they do seem t=
=3D
o degrade faster in soda.=3DA0 In my experience, soda is less invasive, bot=
h =3D
in terms of its effect on the refractory and its effect on the wares.=3DA0 =
Wh=3D
en you say that soda is more corrosive in localized areas, I think that is =
=3D
only because we CAN spray it on the wall or directly on the wares.=3DA0 We =
do=3D
n't do that with salt.=3DA0 I like soda specifically it is less aggressive =
in=3D
its effect on the wares.=3DA0 =3D0A=3D0AWe have had students new to soda w=
ho sim=3D
ply didn't charge nearly enough sodium carbonate solution and got very dry =
=3D
surfaces, far dryer than you get in a residual salt firing in a well-season=
=3D
ed salt kiln where no salt is charged during the firing.=3DA0 I have never =
ru=3D
n a "residual" soda firing, but have heard from others who have tried it an=
=3D
d got almost no soda deposition on the wares - really just the slightest ev=
=3D
idence, primarily visible in the contrast with areas where wadding is touch=
=3D
ing the wares.=3DA0 There just does not seem to be much volatilization of t=
he=3D
soda that has deposited on the refractory or accumulated in the firebox fr=
=3D
om previous firings.=3DA0 That corresponds with the fact that soda volatili=
ze=3D
s best when sprayed into the kiln as a saturated soda ash solution.=3DA0 I =
kn=3D
ow that some people charge with burritos of moistened soda ash mixed with c=
=3D
alcium carbonate and other things, but I find that much harder on the kiln =
=3D
and we try to stay away from
that.=3DA0 We get such great results in our cross-draft soda kiln at tempe=
ra=3D
tures from cone-1 to cone-11.=3DA0 One of my BFA students, Ellen Kleckner, =
ha=3D
s her senior thesis show up right now and it is all cone-1 soda-fired terra=
=3D
cotta using colored terra sigillatas and only small details of glaze here a=
=3D
nd there.=3DA0 She is getting such luscious surfaces.=3DA0 She is going pla=
ces.=3D
=3DA0 =3D0A- Vince=3D0A=3D0AVince Pitelka=3D0AAppalachian Center for Craft=
=3D0ATennesse=3D
e Tech University=3D0Avpitelka@dtccom.net=3D0Ahttp://iweb.tntech.edu/wpitel=
ka/

Vince Pitelka on sun 22 apr 12


Ben Morrison wrote:
"I did not find this to be the case in our soda kiln, however we aren't
spraying the shelves directly, but spraying a hot bag wall in a directional
kiln which blasts the pots with fumes. Were you hitting the shelves directl=
y
with a soda blast?"

Hi Ben -
We spray into the firebox, fanning the spray on the wall above the burner
ports and the floor of the firebox. Whether we use the nitride bonded
Chinese shelves or regular 3/4" silicon carbide shelves, over a period of
years they start to lose their corners and eventually their structural
integrity. This does not happen in salt. Our soda kiln is used pretty
heavily.
- Vince

Vince Pitelka
Appalachian Center for Craft
Tennessee Tech University
vpitelka@dtccom.net
http://iweb.tntech.edu/wpitelka/

jonathan byler on mon 23 apr 12


I just pulled a draw ring from our soda kiln before putting any soda
ash solution in (we use 1-1/2 lb per gallon of water). This kiln has
been fired at least 10 times now, maybe more. There is a pretty good
buildup on the bricks and in the fireboxes, though I used hanks
suggestion and cast pieces to go in them that will get removed when
they have worn out. I wish I had done that with the whole floor...
things for next time...

Anyway, long story short, this draw ring was totally dry, as though it
had been in a regular gas or electric kiln. I charged 1/2 gallon of
soda ash solution, and pulled the next ring and it has a nice glaze to
it already. we could stop there if we wanted to. this kiln is about
30-40 cu ft inside, about 45 with the fireboxes. If you want to not
use so much soda and waste so much time, try shutting off the burners
and closing the damper most of the way when spraying. alternate
spraying with climbing back to temperature. I have been floating
between 2150 and 2250 or so with this, then fire until it's done. You
get buildup much quicker. It will probably have less of a directional
effect, but that is a moot point in our kiln, which is a pretty
standard downdraught design.

jonathan byler on mon 23 apr 12


two things I forgot to mention: don't forget to open the damper before
turning the burners back on, and don't forget to always wear your
safety glasses.

well, that's really one thing: safety first!


On Apr 23, 2012, at 8:45 PM, jonathan byler wrote:

> I just pulled a draw ring from our soda kiln before putting any soda
> ash solution in (we use 1-1/2 lb per gallon of water). This kiln has
> been fired at least 10 times now, maybe more. There is a pretty
> good buildup on the bricks and in the fireboxes, though I used hanks
> suggestion and cast pieces to go in them that will get removed when
> they have worn out. I wish I had done that with the whole floor...
> things for next time...
>
> Anyway, long story short, this draw ring was totally dry, as though
> it had been in a regular gas or electric kiln. I charged 1/2 gallon
> of soda ash solution, and pulled the next ring and it has a nice
> glaze to it already. we could stop there if we wanted to. this
> kiln is about 30-40 cu ft inside, about 45 with the fireboxes. If
> you want to not use so much soda and waste so much time, try
> shutting off the burners and closing the damper most of the way when
> spraying. alternate spraying with climbing back to temperature. I
> have been floating between 2150 and 2250 or so with this, then fire
> until it's done. You get buildup much quicker. It will probably
> have less of a directional effect, but that is a moot point in our
> kiln, which is a pretty standard downdraught design.
>
>