Michelle H. Lowe on sat 4 oct 97
> A more puzzling claim (to me)was made by Soldner in an Idaho workshop back in
> the late '70s when he claimed to be able to bisk fire wet pots. He lost a lot
> more than he said he would. He said something like 85% would make it through
> the firing (of pots thrown that same day!) Less than 50% made it but that any
> did was a total shock to me! How does that work?
>
> He said the moist atmosphere in the kiln was essential. I have wondered about
> it all these long years.
We did some "wet bisque" firings at Arizona State University when I
was taking a clay class up there once in the late 80's. Randy
Schmidt was in charge of those and the success rate was well over 50%
as I remember, closer to the 85% Soldner said. Randy talked about
keeping the atmosphere very very humid throughout the kiln and around
it, which they did by hosing the kiln down while firing it. Worked
pretty well.
Also, one time I was making tiny pinched images of animals at a
community college here in Phoenix and the teacher, loading a bisque,
asked if he could try firing one of these little (solid, maybe 1/2"
thick at the most) figures. I let him stick one in and it bisqued
just fine, from totally wet when loaded in the kiln.
Mishy
Michelle Lowe, potter in the Phoenix desert \|/ |
mishlowe@indirect.com -O- | |
mishlowe@aztec.asu.edu /|\ | | |
|_|_|
http://www.amug.org/~mishlowe ____ |
-\ /-----|-----
( )
<__>
Dannon Rhudy on sun 5 oct 97
Hmmmmm. Someone wrote an article, not too far past, about
raku-firing greenware, but it had to be done while the work was
REALLY wet, straight off the wheel, nearly. Something to do with
the outside still being as wet as the inside, so the water
could get out before a "skin" formed over the clay. It's not
that I did not believe it worked. I just thought the explanation
unlikely. Seemed to me that as soon as it went into the kiln,
the outside would start to dry faster than the inside. However,
I have not tried it, so no personal experience there. Has anyone
done this?
Dannon Rhudy
potter@koyote.com
----------------------------Original
message----------------------------
> A more puzzling claim as I remember,.......... closer to the 85%
Soldner said. Randy talked about
keeping the atmosphere very very humid throughout the kiln and
around
it, which they did by hosing the kiln down while firing it.
Worked
pretty well.
.....................
Bill Walker on sun 5 oct 97
You can wet bisque because of a pressure cooker type concept. When the
kiln is full of steam, the water in the pots can get hotter before it
boils, and the pots sort of dry from the inside out. Ceramics factories
use the same concept for drying stuff like big insulators by carefully
controlling the humidity. Basically they start drying in high humidity
and get the temperature up there, then reduce the humidity so the
water comes off as steam but below the boiling point, and the boiling
point is higher when humidity is higher.
Bill Walker
Alfred NY
walkerw@bigvax.alfred.edu
Tadeusz Westawic on tue 7 oct 97
Dannon Rhudy wrote:
>
> ----------------------------Original message----------------------------
>
> Hmmmmm. Someone wrote an article, not too far past, about
> raku-firing greenware, but it had to be done while the work was
> REALLY wet, straight off the wheel, nearly. Something to do with
> the outside still being as wet as the inside, so the water
> could get out before a "skin" formed over the clay. It's not
> that I did not believe it worked. I just thought the explanation
> unlikely. Seemed to me that as soon as it went into the kiln,
> the outside would start to dry faster than the inside. However,
> I have not tried it, so no personal experience there. Has anyone
> done this?
>
> Dannon Rhudy
> potter@koyote.com
>
> ----------------------------Original
> message----------------------------
> > A more puzzling claim as I remember,.......... closer to the 85%
> Soldner said. Randy talked about
> keeping the atmosphere very very humid throughout the kiln and
> around
> it, which they did by hosing the kiln down while firing it.
> Worked
> pretty well.
>
> ....................
Someone told me the protection for the wet pots was the steam envelope
that developed around the ware. Not only did you have to have very wet
pots, but more than just a few of them.
Tadzu
Fay & Ralph Loewenthal on tue 7 oct 97
Dannon, I mentioned something I read in John Conrad's
book "Ceramic Formulas the complete compendium". My
edition is dated 1976. He mentions the "Wet Fire"
technique. I quote "The object, while still wet, is
covered with an engobe type glaze. This wet object is
placed in a 1700F kiln. The resulting steam creates a
protective envelope around the object and prevents it
from exploding". This quote comes from his chapter on
"Raku Glazes". Hope this helps Ralph in PE SA.
Wendy Hampton on tue 7 oct 97
I took a class at Anderson Ranch from Jim Lawton and having only one week to
make and fire all our pieces we bisqued wet pieces. He left the kiln lid
open till the very end of the firing ( last 50 degrees), and we only lost one
piece out of the whole firing. Some were put in the right off the wheel.
Wendy from Bainbridge Island WA
KEMPB on wed 8 oct 97
About 30 years ago I went to a Paul Soldner raku workshop in
Melbourne, Australia and he espoused the "water blanket" theory and
to prove it, he took pots straight from the wheel and bisqued fired
them in the kiln.......with no mishaps.
Yes, it works.
Brian Kemp. Singapore
kempb@nievax.nie.ac.sg
KDrescherg on wed 8 oct 97
I heard about this from an old professor who did not do pottery. He said that
we were not doing Raku right. We should be glazing our pots while wet and just
like you describe, the put them into a hot kiln. The "steam envelope" will
protect them. I never was brave enough to try it. Anyone out there tried this?
I still think it is a myth.
Chris G.
Rakuing in the heat of the Alabama Indian summer eve...
stevemills on wed 8 oct 97
We use this technique here; we close the kiln right up, set heat input @
10% and soak temp @ 110oC. Leave for 12 hrs preferably 24.
Steve
It's raining!!
In message , Bill Walker writes
>----------------------------Original message----------------------------
>
>You can wet bisque because of a pressure cooker type concept. When the
>kiln is full of steam, the water in the pots can get hotter before it
>boils, and the pots sort of dry from the inside out. Ceramics factories
>use the same concept for drying stuff like big insulators by carefully
>controlling the humidity. Basically they start drying in high humidity
>and get the temperature up there, then reduce the humidity so the
>water comes off as steam but below the boiling point, and the boiling
>point is higher when humidity is higher.
>
>Bill Walker
>Alfred NY
>walkerw@bigvax.alfred.edu
>
--
Steve Mills
@Bath Potters Supplies
Dorset Close
Bath
BA2 3RF
UK
Tel:(44) (0)1225 337046
Fax:(44) (0)1225 462712
kinoko@junction.net on thu 9 oct 97
Chris, Myth or not it was repudedly the explanation of Houdini's ability to
plunge his hand into a pot of molten lead without burning himself. there are
two possible explanations: Houdini stuck kis hand in his armpit prior to
completing the trick,getting it moist. Then, plunged his had into the molten
metal,(which may have been tin rather than lead) the moisture creating an
"envelope of steam." In Nigeria,we were led to believe that the local
pottery was quite wet when stacked for the pit-fire,which was quite 'cool'
through much of the firing. I add here that,in building her very large
pots,Isao often burned a quantity of newspaper INSIDE the pot,to firm it up
prior to adding another coil or two. According to Leach,(A Potters Book)?
the Raku pots were pinched-out,glazed and set atop the rude kiln for a
time,before placing them in the kiln itself. I,(Don) have frequently in the
past stacked wet pots around the outside of the kiln to steam-out. ( when I
was working in Hanazono,Kyoto) Don&
Isao>----------------------------Original message----------------------------
>I heard about this from an old professor who did not do pottery. He said that
> we were not doing Raku right. We should be glazing our pots while wet and just
> like you describe, the put them into a hot kiln. The "steam envelope" will
> protect them. I never was brave enough to try it. Anyone out there tried this?
> I still think it is a myth.
>
>Chris G.
>Rakuing in the heat of the Alabama Indian summer eve...
>
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** Don and Isao Morrill **
** Falkland, B.C. **
** kinoko@junction.net **
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