Gwynneth Rixon on wed 10 nov 10
Hi=3D2C
I have just been reminded never to use a new batch of glaze without test=
=3D
ing....
http://gzandco.blogspot.com/2010/11/glaze-disaster.html
it has crawled for two of us....clean bisque ware=3D2C four different bodie=
s =3D
between us=3D2C same result.
Luckily I couldn't get a big platter into this kiln=3D2C so it has been was=
he=3D
d off ready for next week's firing.
Any ideas?
Gwynneth
www.gwynnethrixonceramics.co.uk
=3D
Lee Love on wed 10 nov 10
On Wed, Nov 10, 2010 at 10:34 AM, Gwynneth Rixon wr=
=3D
ote:
Gwynneth, could you have applied it too thickly?
--=3D20
--
=3DA0Lee, 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
William & Susan Schran User on wed 10 nov 10
On 11/10/10 11:34 AM, "Gwynneth Rixon" wrote:
> I have just been reminded never to use a new batch of glaze without
> testing....
> http://gzandco.blogspot.com/2010/11/glaze-disaster.html
> it has crawled for two of us....clean bisque ware, four different bodies
> between us, same result.
I looked at your blog where you wrote:
Just the usual Shino...AT Ball Clay 1 : China Clay 1: Nepheline Syenite 1
I've not run across a shino glaze like this before, 2/3 clay, but given the
degree of crawling I would suggest this glaze is supposed to crawl if this
indeed is the extent of the recipe. Were I to run across this recipe I woul=
d
have thought it to be some sort of slip.
Crawling is due to the large amount of clay in the recipe. I'd suggest you
might need to calcine almost half the clay to keep it from crawling.
Bill
--
William "Bill" Schran
wschran@cox.net
wschran@nvcc.edu
http://www.creativecreekartisans.com
Craig Martell on thu 11 nov 10
Hello Gwynneth:
Have you used this glaze, prior to the last fire, with good
results? If so, I would think that too thick an application is the
problem. You may want to apply thinner and test that in the next
fire. Also, from what I saw in the photo, the pots are vapor glazed
and the additional fluxing action of the vapor would be necessary
with this particular glaze seeing that it is so very high in clay
content. Hopefully I'm seeing this correctly.
This glaze is so high in alumina that crawling is almost
guaranteed. All the extra clay can result in the glaze cracking in
the raw state and then beading up and not healing and smoothing over
in the fire. Alumina really raises the surface tension of the glaze
when melted. So, you might try lowering the clay content of the
glaze with some line blends. You can also add some additional fluxes
such as Soda Feldspar and some Spodumene or perhaps Petalite.
regards, Craig Martell Hopewell, Oregon
Paul Herman on thu 11 nov 10
Gwynneth,
I am really suspicious of that recipe too. It's two thirds clay, and I
would certainly expect anything as clayey as that to crack and crawl
badly. Have you used it before?
If it were one third clay and two thirds nepheline syenite, it would
be more like other shino recipes I've seen.
good glazing,
Paul Herman
Great Basin Pottery
Doyle, California US
www.greatbasinpottery.com/
On Nov 10, 2010, at 8:34 AM, Gwynneth Rixon wrote:
> Hi,
> I have just been reminded never to use a new batch of glaze
> without testing....
> http://gzandco.blogspot.com/2010/11/glaze-disaster.html
> it has crawled for two of us....clean bisque ware, four different
> bodies between us, same result.
>
> Luckily I couldn't get a big platter into this kiln, so it has been
> washed off ready for next week's firing.
>
> Any ideas?
>
> Gwynneth
>
> www.gwynnethrixonceramics.co.uk
David Finkelnburg on thu 11 nov 10
Gwynneth,
I've gotten Shino to crawl...but never like that! :-( I use only
soda ash Shinos, though, so not quite the same thing as your recipe.
What, precisely, is different with this glaze and firing?
Have you used the recipe before, but with success?
How dense is the biscuit? Soft or hard?
Did the glaze show drying cracks? Was it quite a thick application, or
was it thin? Was the biscuit washed or sponged before glazing? Was the
ware fired while the glaze was still wet or damp?
-----------------------------
Date: Wed, 10 Nov 2010 16:34:59 +0000
From: Gwynneth Rixon
I have just been reminded never to use a new batch of glaze without test=
=3D
ing....
http://gzandco.blogspot.com/2010/11/glaze-disaster.html
it has crawled for two of us....clean bisque ware=3D2C four different bodie=
s =3D
between us=3D2C same result. Any ideas?
Lee Love on thu 11 nov 10
I used a 2/3rds Korean Kaolin and 1/3rd Neph Sye shino in Japan with
great results. You just have to put it on thinner.
--
=3DA0Lee, 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
Edouard Bastarache on thu 11 nov 10
Indeed too much clay.
I would use another recipe, more like the usual ones
http://smart2000.pagesperso-orange.fr/shinos_americains.htm
http://queshinos.blogspot.com/
Gis,
Edouard Bastarache
Spertesperantisto
Sorel-Tracy
Quebec
http://www.flickr.com/photos/30058682@N00/
http://edouardbastarache.blogspot.com/
http://blogsalbertbastarache.blogspot.com/
http://cerampeintures.blogspot.com/
http://www.facebook.com/edouard.bastarache
----- Original Message -----
From: "William & Susan Schran User"
To:
Sent: Wednesday, November 10, 2010 6:09 PM
Subject: Re: Shino disaster....help please!!
> On 11/10/10 11:34 AM, "Gwynneth Rixon" wrote:
>> I have just been reminded never to use a new batch of glaze without
>> testing....
>> http://gzandco.blogspot.com/2010/11/glaze-disaster.html
>> it has crawled for two of us....clean bisque ware, four different bodies
>> between us, same result.
>
> I looked at your blog where you wrote:
> Just the usual Shino...AT Ball Clay 1 : China Clay 1: Nepheline Syenite 1
>
> I've not run across a shino glaze like this before, 2/3 clay, but given
> the
> degree of crawling I would suggest this glaze is supposed to crawl if thi=
s
> indeed is the extent of the recipe. Were I to run across this recipe I
> would
> have thought it to be some sort of slip.
> Crawling is due to the large amount of clay in the recipe. I'd suggest yo=
u
> might need to calcine almost half the clay to keep it from crawling.
>
> Bill
>
> --
> William "Bill" Schran
> wschran@cox.net
> wschran@nvcc.edu
> http://www.creativecreekartisans.com
>
Lee Love on thu 11 nov 10
On Thu, Nov 11, 2010 at 12:08 PM, Paul Herman
wrote:
> Gwynneth,
>
> I am really suspicious of that recipe too. It's two thirds clay, and I
> would certainly expect anything as clayey as that to crack and crawl
> badly. Have you used it before?
This is a standard flashing slip recipe. But, flashing slips are used thin=
=3D
.
--
=3DA0Lee, 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
ivor and olive lewis on fri 12 nov 10
Dear Gwynneth Rixon,
I would need more details. But from the information you provide your glaze
has insufficient melting agents (1/3)to flux that amount of clay (2/3). IN
addition, that proportion of clay in a glaze would shrink causing a high
degree of reticulation (crawling)
Best regards,
Ivor Lewis,
REDHILL,
South Australia
Edouard Bastarache on fri 12 nov 10
If you want lots of clay in a shino glaze try Lasse Ostman's :
http://www.stoneware.net/stoneware/glasyrer/recept/otherred/sh6.htm
Gis,
Edouard Bastarache
Spertesperantisto
Sorel-Tracy
Quebec
http://www.flickr.com/photos/30058682@N00/
http://edouardbastarache.blogspot.com/
http://blogsalbertbastarache.blogspot.com/
http://cerampeintures.blogspot.com/
http://www.facebook.com/edouard.bastarache
| |
|
