David Hendley on sun 29 aug 10
Ohata Khaki has been around so long, who knows what the
"original" recipe might be? Is there a Mr. or Ms. Ohata
somewhere in the past?
Myself, I have no compulsion not to change a glaze recipe
to fit my exact situation.
I find that most old-time, well-worn recipes craze on my
claybody, so I usually add more silica to the formula/recipe.
I often remove dolomite and add talc, because, for me,
talc is a much cheaper source of magnesium. Of course,
the recipe has to be recalculated from formula to recipe.
I use 2 different Ohatas! One is a regular glaze, for application
on bisqueware, the other is a "slip-glaze", for application
on leather hard clay.
Take a look at the two recipes - they are vastly different.
Just glancing, you wouldn't dream that they are the same,
but they are - the unity molecular formulae are identical:
OHATA RED, cone 10
Custer feldspar 54.0
Whiting 11.0
Bone ash 11.0
Talc 8.0
Kaolin 7.0
Flint 24.0
Red iron oxide 12.0
TOTAL 127.0
OHATA SLIP GLAZE, cone 10
Custer feldspar 25.0
Redart clay 32.0
Bone ash 9.0
Whiting 8.3
Red iron oxide 7.2
Talc 4.5
Flint 13.0
Soda ash 1.0
TOTAL 100.0
This is an excellent example of why glaze calculation on
the molecular level is such a valuable tool.
Gene, you have it all wrong as far as the desired firing for
an iron saturate glaze such as this. Oxidation firing is actually
the preferred ideal. The glaze can look OK in reduction
(I always fire reduction), but it is really at it's best without
reduction.
David Hendley
david@farmpots.com
http://www.farmpots.com
http://www.thewahooligans.com
----- Original Message -----
Will the real Ohata Kaki recipe please stand up.
While doing a search to find the recipe for Ohata at least five different
recipes came up.
Is there an original Ohata Kaki?? I'm assuming that all the ones that I
found were based on an original and then tweaked to suit the user.
mudduck on sun 29 aug 10
Will the real Ohata Kaki recipe please stand up.
While doing a search to find the recipe for Ohata at least five =3D
different recipes came up. All had the same ingredients but used =3D
different percents. Only two added up to 100.
Is there an original Ohata Kaki?? I'm assuming that all the ones that I =3D
found were based on an original and then tweaked to suit the user.
Is anyone using Ohata glaze or a tweaked version that you would be =3D
willing to share. If you are using Ohata how much reduction will it take =
=3D
and still stay red??
I fire in a gas kiln to a soft cone 10 in light reduction.
Thanks!!!
Gene
mudduck@mudduckpottery.net
www.mudduckpottery.net
Larry Kruzan on sun 29 aug 10
Hi Gene,
I like Bailey's Red better than Ohata - much more dependable, better
saturated iron color IMHO. Will work in reduction or oxidation.
Larry Kruzan
Lost Creek Pottery
www.lostcreekpottery.com
-----Original Message-----
From: Clayart [mailto:Clayart@LSV.CERAMICS.ORG] On Behalf Of mudduck
Sent: Sunday, August 29, 2010 1:46 PM
To: Clayart@LSV.CERAMICS.ORG
Subject: ohata kaki
Will the real Ohata Kaki recipe please stand up.
While doing a search to find the recipe for Ohata at least five different
recipes came up. All had the same ingredients but used different percents.
Only two added up to 100.
Is there an original Ohata Kaki?? I'm assuming that all the ones that I
found were based on an original and then tweaked to suit the user.
Is anyone using Ohata glaze or a tweaked version that you would be willing
to share. If you are using Ohata how much reduction will it take and still
stay red??
I fire in a gas kiln to a soft cone 10 in light reduction.
Thanks!!!
Gene
mudduck@mudduckpottery.net
www.mudduckpottery.net
=3D=3D=3D=3D=3D=3D=3D
Email scanned by PC Tools - No viruses or spyware found.
(Email Guard: 7.0.0.18, Virus/Spyware Database: 6.15750)
http://www.pctools.com/
=3D=3D=3D=3D=3D=3D=3D
William & Susan Schran User on sun 29 aug 10
On 8/29/10 2:46 PM, "mudduck" wrote:
> Will the real Ohata Kaki recipe please stand up.
> While doing a search to find the recipe for Ohata at least five different
> recipes came up. All had the same ingredients but used different percents=
.
> Only two added up to 100.
> Is there an original Ohata Kaki?? I'm assuming that all the ones that I f=
ound
> were based on an original and then tweaked to suit the user.
> Is anyone using Ohata glaze or a tweaked version that you would be willin=
g to
> share. If you are using Ohata how much reduction will it take and still s=
tay
> red??
> I fire in a gas kiln to a soft cone 10 in light reduction.
I don't know if the Ohata Kaki listed on my web site is the original or not=
,
but we fired to full ^10, light reduction (back pressure, no flame or smoke
from stack). I tried several versions and found the one we used to work bes=
t
for us at school on several different clays.
Here's the link for the ^10 glazes:
http://www.creativecreekartisans.com/creativecreek_cone10re.htm
Bill
--
William "Bill" Schran
wschran@cox.net
wschran@nvcc.edu
http://www.creativecreekartisans.com
Suchman ceramics on mon 30 aug 10
Can we get this as a ^6 version?
On Mon, Aug 30, 2010 at 4:24 PM, Vince Pitelka wrote:
> Ohata Kaki was one of my stable glazes when I was making pots full time i=
n
> Northern California, and now it is one of our stable glazes at the Craft
> Center. This is the same recipe I got from Humboldt State University in
> the
> late 1960s, with the exception of having substituted Custer feldspar for
> the
> old Oxford or Kingman feldspars.
>
> Ohata Kaki - C10 ox. or reduc.
> G-200 Feldspar ----- 48.7
> Flint -------------- 21.6
> Bone Ash ------------ 9.9
> Whiting ------------- 7.2
> EPK ----------------- 6.3
> Talc ---------------- 6.3
> Total ------------- 100.0
> + Red Iron Oxide --- 11%
>
> - Vince
>
> Vince Pitelka
> Appalachian Center for Craft
> Tennessee Tech University
> vpitelka@dtccom.net; wpitelka@tntech.edu
> http://iweb.tntech.edu/wpitelka
>
--
-e-in-o'side-
pagan by nature
>http://www.flickr.com/photos/42169721@N04/
Hank Murrow on mon 30 aug 10
On Aug 30, 2010, at 4:24 PM, Vince Pitelka wrote:
> Ohata Kaki was one of my stable glazes when I was making pots full =3D
time in
> Northern California,
My experience also...... just don't leave out the bone ash or other =3D
source (if you can find one) of Phosphorus if you expect iron red. =3D
There's 9.9% in Vince's version.
I have 32.4% in one of my iron reds!
Cheers, Hank=3D
Vince Pitelka on mon 30 aug 10
Ohata Kaki was one of my stable glazes when I was making pots full time in
Northern California, and now it is one of our stable glazes at the Craft
Center. This is the same recipe I got from Humboldt State University in th=
e
late 1960s, with the exception of having substituted Custer feldspar for th=
e
old Oxford or Kingman feldspars.
Ohata Kaki - C10 ox. or reduc.
G-200 Feldspar ----- 48.7
Flint -------------- 21.6
Bone Ash ------------ 9.9
Whiting ------------- 7.2
EPK ----------------- 6.3
Talc ---------------- 6.3
Total ------------- 100.0
+ Red Iron Oxide --- 11%
- Vince
Vince Pitelka
Appalachian Center for Craft
Tennessee Tech University
vpitelka@dtccom.net; wpitelka@tntech.edu
http://iweb.tntech.edu/wpitelka
Ric Swenson on tue 31 aug 10
Here's the one I have. I have had it so long I don't remember where I got =
it. It may have come through a book..... or F.C Ball or Fred Olsen in grad =
school.? My notebook ascribes no original source.
Potash Feldspar 43.92
Flint 19.51
EPK 5.69
Talc 5.69
whiting 6.50
bone ash 8.94
red iron oxide 9.75
-----------------------------
100 %
Cone ten, nice on porcelain in oxidation fire.
Variation: add 5% rutile. yields Rust/green
------------------------------------------------
Regards,
Ric
"...then fiery expedition be my wing, ..."
-Wm. Shakespeare, RICHARD III, Act IV Scene III
Richard H. ("Ric") Swenson, Teacher,
Office of International Cooperation and Exchange of Jingdezhen Ceramic Inst=
itute,
TaoYang Road, Eastern Suburb, Jingdezhen City.
JiangXi Province, P.R. of China.
Postal code 333001.
Mobile/cellular phone : 86 13767818872
< RicSwenson0823@hotmail.com>
http://www.jci.jx.cn
> Date: Sun, 29 Aug 2010 15:32:44 -0400
> From: wschran@COX.NET
> Subject: Re: ohata kaki
> To: Clayart@LSV.CERAMICS.ORG
>
> On 8/29/10 2:46 PM, "mudduck" wrote:
>
> > Will the real Ohata Kaki recipe please stand up.
> > While doing a search to find the recipe for Ohata at least five differe=
nt
> > recipes came up. All had the same ingredients but used different percen=
ts.
> > Only two added up to 100.
> > Is there an original Ohata Kaki?? I'm assuming that all the ones that I=
found
> > were based on an original and then tweaked to suit the user.
> > Is anyone using Ohata glaze or a tweaked version that you would be will=
ing to
> > share. If you are using Ohata how much reduction will it take and still=
stay
> > red??
> > I fire in a gas kiln to a soft cone 10 in light reduction.
>
> I don't know if the Ohata Kaki listed on my web site is the original or n=
ot,
> but we fired to full ^10, light reduction (back pressure, no flame or smo=
ke
> from stack). I tried several versions and found the one we used to work b=
est
> for us at school on several different clays.
> Here's the link for the ^10 glazes:
> http://www.creativecreekartisans.com/creativecreek_cone10re.htm
>
> Bill
>
> --
> William "Bill" Schran
> wschran@cox.net
> wschran@nvcc.edu
> http://www.creativecreekartisans.com
Vince Pitelka on tue 31 aug 10
In response to the Ohata Kaki recipe I posted (included below), Eric Suchma=
n
asked:
"Can we get this as a ^6 version?"
Eric -
I don't have a cone-6 version, but anyone could convert the formula with
glaze-calculation software. You would have to do extensive testing and
would probably need to modify the formula to get the best performance. I d=
o
not know anything about saturated iron reds at cone-6.
- Vince
Vince Pitelka
Appalachian Center for Craft
Tennessee Tech University
vpitelka@dtccom.net; wpitelka@tntech.edu
http://iweb.tntech.edu/wpitelka
> Ohata Kaki was one of my stable glazes when I was making pots full time i=
n
> Northern California, and now it is one of our stable glazes at the Craft
> Center. This is the same recipe I got from Humboldt State University in
> the
> late 1960s, with the exception of having substituted Custer feldspar for
> the
> old Oxford or Kingman feldspars.
>
> Ohata Kaki - C10 ox. or reduc.
> G-200 Feldspar ----- 48.7
> Flint -------------- 21.6
> Bone Ash ------------ 9.9
> Whiting ------------- 7.2
> EPK ----------------- 6.3
> Talc ---------------- 6.3
> Total ------------- 100.0
> + Red Iron Oxide --- 11%
>
> - Vince
William & Susan Schran User on wed 1 sep 10
On 8/31/10 6:47 PM, "Vince Pitelka" wrote:
> In response to the Ohata Kaki recipe I posted (included below), Eric Such=
man
> asked:
> "Can we get this as a ^6 version?"
> I don't have a cone-6 version, but anyone could convert the formula with
> glaze-calculation software. You would have to do extensive testing and
> would probably need to modify the formula to get the best performance. I=
do
> not know anything about saturated iron reds at cone-6.
Diane Panicioli's web site is a good place to start for ^6 reduction glazes=
.
John Britt had an article on ^6 reduction glazes in CM not too long ago.
Check the archives for several postings on this subject.
On my web site I have a page of ^6 reduction glazes, including ohata kaki.
Lithium as a secondary flux to bring down to ^6.
Bill
--
William "Bill" Schran
wschran@cox.net
wschran@nvcc.edu
http://www.creativecreekartisans.com
dianamp@COMCAST.NET on wed 1 sep 10
When I worked at Pewabic in the early 80's
they had a glaze called OHarata Red.
I think it was the same thing as OHata Kaki
(just a mis-spelling and/or mis-pronounciation of OHarata)
I am traveling at the moment and can't check my notebook
but will post the OHarata glaze when I get back
to see if it is the same formula.
If so, OHarata may give us a clue as to its origin.
Diana Pancioli
E.M.U.
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