r horning on sat 27 dec 03
"Has any urban potter had any experience with salt or soda kilns in
polution
sesitive areas such as Los Angeles.
I'd like to build a soda kiln, but I don't want to attract the
attention of
the fire marshal until I have explored the territory.
Any sharing of the experience would be greatly appreciated
Donald"
Donald, I have a salt kiln in suburban Detroit. The local building
department did not know how to classify it. So they have given it
the restrictions they give an outdoor barbecue. It must be 24"
from any structure. The mechanical inspection was just on the
plumbing. They didn't understand the rest of it. If it doesnt fit into
their current code, they don't seem to be concerned. I did not mention
that I would be introducing salt. When I add salt, I close the
damper most of the way, as suggested by clayarters. Not only does
this keep the sodium chloride in the kiln until it burns, it also makes
for fewer white clouds above the kiln at that point. So far, I have not
had a visit from the city when firing.
Good luck, Rebecca
---------------------------------
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Steve Mills on tue 30 dec 03
There seem to be as many ways to deliver soda into a Kiln as there is
with salt, yet I haven't met anyone so far who is doing what I do but
with Soda.
Worth a try?
Steve
In message , Lee Love writes
>----- Original Message -----
>From: "Steve Mills"
>To:
>Sent: Monday, December 29, 2003 7:18 AM
>Subject: Re: Soda Kiln in ther big city
>
>
>> I salt glaze in the style I was taught by my French Mentor; 2 little
>> pots of salt set in between the fire and the setting.
>Steve, do you know anybody doing this with soda? I wonder how one
>might change the amount and delivery? Soda tends to volitise at a low=
>er
>temp. The interior of my kiln is soft brick and also, I like the color=
>s I
>get with soda..
>
>Thanks,
>--
>Lee In Mashiko, Japan
--
Steve Mills
Bath
UK
Lee Love on tue 30 dec 03
----- Original Message -----
From: "Steve Mills"
> There seem to be as many ways to deliver soda into a Kiln as there is
> with salt, yet I haven't met anyone so far who is doing what I do but
> with Soda.
Maybe with soda, it would be better if I sprayed it in, in solution.
Back home, I've experimented with dipping work in soda before firing. I
had some good luck with porcelain and white stoneware.
--
Lee In Mashiko, Japan
http://Mashiko.us
Web Log (click on recent date):
http://www.livejournal.com/users/togeika/calendar
iandol on wed 31 dec 03
Dear Friends,
Once again people are distributing misinformation about the properties =
of the materials clayworkers use.=20
There seems to be some misunderstanding about the Chemistry of Sodium =
Carbonate.
It is doubtful if this material is capable of rapidly changing into a =
vapour. Its melting point: 851=BA C (Kay and Laby), 858.1=BA (CRC =
Handbook of Ch & Ph) gives us some idea of the temperature where is will =
become a liquid. As far as I can gather its Decomposition Temperature is =
undetermined so we have no way of knowing if it will spontaneously =
discharge Carbon Dioxide, though the footnote in P. J. Durrant (p.319) =
casts doubt on the potential for this reaction. (Someone may like to do =
the Calcs to determine a theoretical temperature for spontaneous =
composition). Durrant make it quite clear that in contact with Porcelain =
there is a strong reaction whereas when heated in a Platinum crucible =
weight loss is negligible. Sodium carbonate reacts rapidly with Silicon =
dioxide. Facts can be verified with simple bench experiments.
My reading about the use of Sodium carbonate as a glazing agent is that =
it is best introduced into the kiln as a Sprayed Hot Saturated Solution. =
Evaporation will create an aerosol atmosphere as droplets circulate =
around the interior of a kiln and the high temperature will melt the =
solid fragments. If there is no draught through the kiln, the damper =
being closed, this dust will settle on the clay and react directly with =
any free silica or silicate minerals.
Seems simple ! No nasty pollutants
Best regards,
Ivor Lewis. Redhill, South Australia
Hendrix, Taylor J. on wed 31 dec 03
Lee and others,
Sometimes all one has are books and 'reading about it.'
Phil Rogers is of a mind that soda glazing possesses more subtleties
than does salt glazing. He speculates that the vapor (or whatever is
really happening, Ivor) resultant from introducing soda into the kiln is
comparatively less vigorous in its activities. Hence the need for more
injection ports into a soda kiln than a similar salt kiln. I'm guessing
(big fat guess here since I have no, none, nada experience here) that
because the two materials have completely different reactions to the
kiln's heat (oh Ivor don't make me explain something I don't really
understand!...yet) we see, not always, differences in the results.
As an aside, Rogers thinks that salt firing may actually be more
environmentally friendly, less polluting, than is soda firing. Me no
know.
Taylor, in Waco
-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of Lee Love
Sent: Wednesday, December 31, 2003 9:25 AM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: Soda Kiln in the big city
----- Original Message -----
From: "iandol"
...
Sometimes actually using the materials is better than reading
about
them.
I've always introduced both salt and soda with water: rock salt
being soaked in water and soda being in a saturated solution. It has
been
my experience that Soda ash solution is more corrosive than Sodium
bicarbonate.
...
Lee Love on thu 1 jan 04
----- Original Message -----
From: "Hendrix, Taylor J."
>As an aside, Rogers thinks that salt firing may actually be more
>environmentally friendly, less polluting, than is soda firing. Me no
>know.
Does he explain why he thinks so? For me, the choice is esthetic
and practical:
I'm not fond of pigskin,
I like the bright colors you can get from soda,
it doesn't bleach shino
is easier on softbrick
and will work at a lower temp than salt.
Next firing I'll experiment with localized soda and also with
applications of soda on my shigaraki clay. I will also try mixing soda
withh wood ash and applying it to shigaraki. Depending on how that turns
out, I may try spraying some in on the door side, where the unglazed work
tends to be dry.
--
Lee In Mashiko, Japan
http://Mashiko.org
Web Log (click on recent date):
http://www.livejournal.com/users/togeika/calendar
iandol on thu 1 jan 04
Dear Lee Love,=20
You are correct, I have not used Sodium Carbonate as a vapour glazing =
medium. Nor would I wish to. Whether using the salt or the carbonate, =
the glaze is suspect and prone to widespread crazing. There is =
difference between confusion and disregarding the facts.
Molten NaCl (MP 805) and Na2CO3 (MP 857), will react with clay or a clay =
body. This could be as low as ^014.
Dipping a pot in a solution is not a form of vapour glazing. Spraying a =
hot saturated solution is still the best way of distributing sodium =
carbonate into a kiln
If you are going to make statements about events which happen associated =
with your firings, such as carbonates being more corrosive than =
Bi-carbonates you must qualify your information with facts and =
circumstances for it to serve any purpose.
Enjoy your Year.
Best regards,
Lee Love on thu 1 jan 04
----- Original Message -----
From: "iandol"
>Once again people are distributing misinformation about the
>properties of the materials clayworkers use.
You are the confused one Ivor. ;^) If you don't understand, it is best to
ask for clarification.
>My reading about the use of Sodium carbonate as a glazing agent
Sometimes actually using the materials is better than reading about
them.
I've always introduced both salt and soda with water: rock salt
being soaked in water and soda being in a saturated solution. It has been
my experience that Soda ash solution is more corrosive than Sodium
bicarbonate.
I don't know if it would work if you put cups of soda solution
around the pots the same way people use salt. Of course, you'd probably
want to do this in non-porous containers. I will experiment. Folks
sometimes mix soda with salt too.
An instructor at South High in Minneapolis (I can't remember his
name, maybe Mel does?) has had good results with Soda at (I think it was
cone 1)or it could be cone 3 (can't remember) but I saw the pots and they
looked pretty nice. He did a presentation at the UofMN shortly after
coming back from a residency at Banff. It is possible to use Soda at lower
temperature than salt. When sprayed in, in solution, it will reacted with
the clay body at a lower temperature.
Spraying isn't the best way to get soda on the pots. Dipping them
in a saturated solution is the best way, but I've only had good results with
porcelain and white stoneware. My stoneware containing iron didn't come
out so well, kind of burnt looking. I still have the mix in my glaze book
from CM April '84 Page 38:
12 cups soda ash
3 gallons water
Soda porcelain. Let dry for one week. Reduce after 1850*F
--
Lee In Mashiko, Japan
http://Mashiko.org
Web Log (click on recent date):
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steve harrison on thu 1 jan 04
Hi Ivor ,
I think that I remember reading in the British Pharmacopia that soda bi =20=
carb dissociates to the carbonate, then to a liquid phase and then very =20=
slowly to vapour. I don't recall the temperatures and I no longer have =20=
access to a copy, perhaps another clayarter does.
Best wishes
Steve Harrison
Hot & Sticky Pty Ltd
5 Railway Pde
Balmoral Village
NSW 2571
Australia
http://ian.currie.to/sh/Steve_Harrisons_books.html
On Wednesday, December 31, 2003, at 11:44 AM, iandol wrote:
> Dear Friends,
> Once again people are distributing misinformation about the properties =
=20
> of the materials clayworkers use.
> There seems to be some misunderstanding about the Chemistry of Sodium =
=20
> Carbonate.
> It is doubtful if this material is capable of rapidly changing into a =20=
> vapour. Its melting point: 851=BA C (Kay and Laby), 858.1=BA (CRC =
Handbook =20
> of Ch & Ph) gives us some idea of the temperature where is will become =
=20
> a liquid. As far as I can gather its Decomposition Temperature is =20
> undetermined so we have no way of knowing if it will spontaneously =20
> discharge Carbon Dioxide, though the footnote in P. J. Durrant (p.319) =
=20
> casts doubt on the potential for this reaction. (Someone may like to =20=
> do the Calcs to determine a theoretical temperature for spontaneous =20=
> composition). Durrant make it quite clear that in contact with =20
> Porcelain there is a strong reaction whereas when heated in a Platinum =
=20
> crucible weight loss is negligible. Sodium carbonate reacts rapidly =20=
> with Silicon dioxide. Facts can be verified with simple bench =20
> experiments.
> My reading about the use of Sodium carbonate as a glazing agent is =20
> that it is best introduced into the kiln as a Sprayed Hot Saturated =20=
> Solution. Evaporation will create an aerosol atmosphere as droplets =20=
> circulate around the interior of a kiln and the high temperature will =20=
> melt the solid fragments. If there is no draught through the kiln, the =
=20
> damper being closed, this dust will settle on the clay and react =20
> directly with any free silica or silicate minerals.
> Seems simple ! No nasty pollutants
> Best regards,
> Ivor Lewis. Redhill, South Australia
>
> =
_______________________________________________________________________=20=
> _______
> 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 =20
> melpots@pclink.com.
>
>
Bruce Girrell on fri 2 jan 04
Have you contacted Gail Nichols?
She lives and fires in an urban area and has probably tried just about every
method of delivering the soda.
Also, Ruthanne Tudball has definitely done the soda-in-a-dish thing. See
http://www.northwalespotters.co.uk/summer2000/soda.htm
Bruce "never too late to jump into a thread" Girrell
Steve Mills on fri 2 jan 04
I must admit I would be tempted to use Soda in the same way as I use
salt; after all the gas velocity at maximum temperature means that most
of the vapours go up the flue instead of hanging around as they do at
earlier stages in the firing.
Steve
In message <014701c3ce75$96eff6b0$b716a2db@togeika>, Lee Love
writes
>
>----- Original Message -----
>From: "Steve Mills"
>
>> There seem to be as many ways to deliver soda into a Kiln as there is
>> with salt, yet I haven't met anyone so far who is doing what I do but
>> with Soda.
>
> Maybe with soda, it would be better if I sprayed it in, in solution.
>Back home, I've experimented with dipping work in soda before firing. I
>had some good luck with porcelain and white stoneware.
>
>--
>Lee In Mashiko, Japan
>http://Mashiko.us
>Web Log (click on recent date):
>http://www.livejournal.com/users/togeika/calendar
>
--
Steve Mills
Bath
UK
Lee Love on fri 2 jan 04
----- Original Message -----
From: "Steve Mills"
> I must admit I would be tempted to use Soda in the same way as I use
> salt; after all the gas velocity at maximum temperature means that most
> of the vapours go up the flue instead of hanging around as they do at
> earlier stages in the firing.
I know some folks mix salt and soda. I suppose adjusting the mix
would regulate the volatility of it.
--
Lee In Mashiko, Japan
http://Mashiko.us
Web Log (click on recent date):
http://www.livejournal.com/users/togeika/calendar
Lee Love on sat 3 jan 04
----- Original Message -----
From: "Bruce Girrell"
> Also, Ruthanne Tudball has definitely done the soda-in-a-dish thing. See
> http://www.northwalespotters.co.uk/summer2000/soda.htm
Thank you Bruce!
This is certainly a small world.... Ruthanne visited Japan last year. I
met her at Shimaoka's workshop when Euan Craig brought her over to meet
Shimaoka Sensei. She gave Shimaoka a pot and he put it on display between
a Hamada and a Kawaii (If I remember correctly, it was a tall teapot.) The
only time in 3 years I saw the work of a living potter so honored. ;^)
Later that day, Euan had me over to visit for dinner with Ruthanne
and her friend. I may have heard about using glazed dishes for soda from
her. Euan later told me, she was thinking about building the kiln design
that Euan and I use. At the time, she explained that her workspace was so
small, that as soon as she finished making a work, she'd load it into the
kiln. She single fires.
The other interesting thing related to "a small world": at the
time, there was a German potter, from near Dresden (old E. Germany) studying
at the workshop for a couple months (he was studying under a grant.) One
of his specialties is wet faceting. He first got this idea from a visit
to Israel. He saw a video of Tudball using this technique and started
doing it himself, except he also added the throwing of the form after
faceting, like Hank does. So he was really happy to meet the person he
learned this from.
Thanks again,
--
Lee In Mashiko, Japan
http://Mashiko.us
Web Log (click on recent date):
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