CFisher995@aol.com on tue 6 aug 96
I recently bought the book "The Potter's Palette" by Christine Constant and
Steve Ogden, Quatro Inc., c 1996. In the book they do 7 generic glaze
recipes (raku, 3 akaline glazes, lead, felspar/dolomite glaze, postash
feldspar/zinc/calcium glaze. The feldspar /dolomite and the potash
feldspar/zinc/calcium glazes I am interested in trying but they are cone 10.
What would I have to do to them to make them cone 5/6 glazes?
They are:
Feldspar/Dolomite Glaze
Potash Felspar 50 parts
Dolomite 20 parts
China Clay 20 parts
Bone Ash 10 parts
Potash Feldspar/Zinc/Calcium Glaze
Potash Felspar 37 parts
Whiting 13 parts
Zinc Oxide 12 parts
China Clay 22 parts
Flint 16 parts
Marcia Selsor on tue 6 aug 96
According to Whinney from the Tech Staff of Ceramics Monthly, the rule of
thumb for conversion from C/10 to C/6 is: replace the feldspar with Neph.
Syen. and add 10% Colemanite (Gerstley Borate). Sometimes you need to
adjust but it works pretty well.
Rlucas on sun 12 dec 10
I have all cone 5 clays from Laguna Clay. I run into a lot of cone 6
glazes.
I am confused, can they or not, be used on cone 5 clay?? If so would you
fire to cone 6?
If there are so many cone 6 glazes, why are there not any cone 6 clays?
William & Susan Schran User on sun 12 dec 10
On 12/12/10 2:31 PM, "Rlucas" wrote:
> I have all cone 5 clays from Laguna Clay. I run into a lot of cone 6
> glazes.
> I am confused, can they or not, be used on cone 5 clay?? If so would you
> fire to cone 6?
> If there are so many cone 6 glazes, why are there not any cone 6 clays?
There are plenty of ^6 clays out there.
I have used a few from Laguna Clay.
Many clays listed for ^5 will work at ^6.
I have used Laguna's ^5 B-Mix for my crystalline glazed work.
The work heat in these firing schedules have ^7 going flat, yet the clay
worked just fine.
Just need to spend some time testing clays with your glazes fired to your
desired temperature and see what happens.
Bill
--
William "Bill" Schran
wschran@cox.net
wschran@nvcc.edu
http://www.creativecreekartisans.com
John Rodgers on sun 12 dec 10
Most C-5 clays, though perhaps not all, will go to C-6 easily enough.
I use C-5 B-mix at cone 6 all the time. No problems.
As always - Test, Test, Test!
John
John Rodgers
Clayartist and Moldmaker
88'GL VW Bus Driver
Chelsea, AL
Http://www.moldhaus.com
On 12/12/2010 1:31 PM, Rlucas wrote:
> I have all cone 5 clays from Laguna Clay. I run into a lot of cone 6
> glazes.
>
> I am confused, can they or not, be used on cone 5 clay?? If so would you
> fire to cone 6?
>
> If there are so many cone 6 glazes, why are there not any cone 6 clays?
>
>
C Sullivan on sun 12 dec 10
On Sun, Dec 12, 2010 at 11:31 AM, Rlucas wrote:
If there are so many cone 6 glazes, why are there not any cone 6 clays?
There are. Georgies has an excellent clay (G-Mix 6 with Grog) which is
spoze to be fired at Cone 6, but does beautifully at cone 5 thru cone 7.
Also, many glazes are versatile enough to do the same thing. (Some aren't,
tho)
Chae
On Sun, Dec 12, 2010 at 11:31 AM, Rlucas wrote:
> I have all cone 5 clays from Laguna Clay. I run into a lot of cone 6
> glazes.
>
> I am confused, can they or not, be used on cone 5 clay?? If so would you
> fire to cone 6?
>
> If there are so many cone 6 glazes, why are there not any cone 6 clays?
>
Lili Krakowski on mon 13 dec 10
Rlucas writes:
"On 12/12/10 2:31 PM, "Rlucas" wrote:
" I have all cone 5 clays from Laguna Clay. I run into a lot of cone 6 =3D
glazes. I am confused, can they or not, be used on cone 5 clay?? If so =3D
would you fire to cone 6? If there are so many cone 6 glazes, why are =3D
there not any cone 6 clays?"
There ARE no cone 6 glazes, and there ARE no cone 6 clays.
Nor c. 5 or 3 or whatever.
Clay bodies are designed to DO BEST at certain temperatures. That means =
=3D
that at that chosen temperature the clay has less than a certain amount =3D
of absorption, has less than a certain amount of shrinkage --besides =3D
having other desirable characteristics. Rhodes goes into a very good =3D
description of all that. I fire at c 6, use bodies that absorb no more =
=3D
than 1.5% water, shrink no more than 12%.=3D20
Furthermore: as kilns fire differently, and large kilns often fire =3D
unevenly, a clay body should be able to do okay for at least 2 cones =3D
below, and 2 above its "official" temp. NOT great and terrific. Okay.
The same applies to glazes. Someone might use a "c. 6 glaze" at c.5 for =
=3D
a matter, duller look, or c.7 for more shine and transparency. With =3D
glaze it is the durability that matters, that the surface heals =3D
properly, that the glaze fits properly and so on. .And generally, for =3D
colored glazes the given cone is the one at which the originator likes =3D
the color best
So when clay body manufacturers say a clay is a c.5 clay, they are =3D
telling you that this body should do well at c.5. It does not mean that =
=3D
it will do poorly at c. 6, or c.4... just that, in the manufacturer's =3D
opinion, and in his lab, that is the best...
Labelling the clays and glazes by cone is a convenience. A shorthand.
Think of children's books. They are marked "Ages 4 to 8" or like that. =
=3D
What does that mean? It means several things. (Or did in my days in =3D
the book trade.) It means that a bright 4 year old from a literate =3D
home would understand the vocabulary. It means that a slower 8 year =3D
old, or one from a background where English was not the common language, =
=3D
would understand the book and still find the topic, story interesting. =
=3D
When a book is marked for teenagers it generally means that the subject =3D
matter is mature enough for teenagers, but perhaps a bit too adult for =3D
younger children...although I have no idea what that would mean today.
So think of all those cone labels as parameters. Test each glaze, each =3D
body at the "advertized" cone and see how it works. =3D20
.Lili Krakowski
Be of good courage
Kathy Forer on mon 13 dec 10
On Dec 13, 2010, at 12:15 AM, Lili Krakowski wrot=
e=3D
:
> So think of all those cone labels as parameters. Test each glaze, each b=
o=3D
dy at the "advertized" cone and see how it works.
My local Ceramic Supply had tiles of each clay fired to different cones. Yo=
u=3D
could easily see in the terracottas how they would get darker with more he=
a=3D
t and paler with less. http://www.7ceramic.com/Merchant2/merchant.mvc?Scree=
n=3D
=3D3DCTGY&Category_Code=3D3DCLAY_0100
http://www.digitalfire.com/4sight/pictures/glossary.html has a few pictures=
o=3D
f glazes fired at different temps.
Kathy
=3D20=3D
Steve Slatin on mon 13 dec 10
Couple of points here -- first, there are plenty of
cone 6 clays. Laguna doesn't make them, so if you
insist on the "cone 6" label, go to another manufacturer.
Second, all clays 'work' (to the extent that they do work
at all) within a range -- Laguna's ^5 clays all seem to
work OK at ^6.
Third, some clays marked ^5 (or ^6 or ^10) really do better
at ^6. B-Mix ^5, for example, tests a little too absorbent
for my taste at ^5. It's actually better at ^6. My
studio mates like it, I don't, particularly. No big deal.
It's confusing, but there's no dictatorial standard for
what ^5 or ^6 even means -- Orton and Seger are slightly
different -- and different kiln manufacturers obtain their
heat work with different firing ramps (as do different
potters). =3D20
Steve Slatin --=3D20
--- On Sun, 12/12/10, Rlucas wrote:
\> I have all cone 5 clays from Laguna
> Clay.=3DA0 I run into a lot of cone 6
> glazes.
>=3D20
> I am confused, can they or not, be used on cone 5
> clay??=3DA0 If so would you
> fire to cone 6?
>=3D20
> If there are so many cone 6 glazes, why are there not any
> cone 6 clays?
=3D0A=3D0A=3D0A
David Woof on tue 14 dec 10
Steve touches some points that need consideration by anyone who is serious =
=3D
about producing durable work for public consumption be it knick-knacks=3D2C=
s=3D
culpture=3D2C or Vessels of domestic utility. All clays do work to some ex=
te=3D
nt as steve says if they hold the form and one fires to something near matu=
=3D
ration range for that particular clay. =3D20
=3D20
Aside from weathering and freezing issues=3D2C where it does become a serio=
us=3D
issue for both potter and consumer is when the absorption % is high and so=
=3D
meone buys one's curious and exuberant creation=3D2C rushes off to fill it =
wi=3D
th water=3D2C and the next AM or at your next art sale comes screeching abo=
ut=3D
a ruined table surface from the wet foot the under fired clay pot caused b=
=3D
ecause you the potter did not do your own test for absorption at your prefe=
=3D
rred firing temp and method. Certainly not an ethical sale and=3D2C rightl=
y =3D
so=3D2C bad for your business. Consider and imagine too the embarrassment f=
or=3D
someone who trusting and unwittingly buys a gift and the same scenario pla=
=3D
ys for the friend. =3D20
=3D20
Don't take=3D2C as holy gospel of ceramics=3D2C commercial designations li=
ke ^=3D
6-10=3D2C or ^5 or any other. To maintain the elevation of our craft=3D2C=
and=3D
raise the bar we should all aspire to professionalism in all we do or get =
=3D
the hell out of the field.=3D20
Even the part timer hobbyist working in a converted water closet can join t=
=3D
his aspiration to educated excellence. One should educate oneself beyond t=
=3D
he questions asked and answered here on Clayart. Our archives will blow yo=
=3D
u away as will some of the good text resources out there. Think=3D2C que=
st=3D
ion everything=3D2C ask=3D2C study=3D2C test=3D2C think and test=3D2C test =
some more.=3D
=3D20
=3D20
Recent post example: folks that don't participate in the above education ar=
=3D
e the real "Dorks"=3D2C not those of us who have studied the physics of ga=
ss=3D
es and in perfect safety torch our freezing propane tanks because we know w=
=3D
hat we are doing!!! (did I really say that?) Don't try this if you are stu=
=3D
pid=3D2C scared=3D2C lack proper education in this matter=3D2C and/or don't=
have =3D
adequate kahoonies and smarts=3D2C or were still sticking your tongue on su=
b =3D
zero mail boxes and pump handles past the age of ten... What you fear will=
=3D
be first in line to kill you!!!
=3D20
Each firing should have test tiles or pieces reflecting one's continuing ed=
=3D
ucation and excitement over possibilities of discovery. One does well to as=
=3D
k "am I spending my evenings drowning my despaired boredom in cyberspace=3D=
2C=3D
or watching TV and slobbering down pizza and cheap beer while drooling and=
=3D
scratching myself like a dog?" vs skipping about down there in the studio =
=3D
fully absorbed with anticipation about what may come out of the next kiln.
=3D20
Speaking of different clays for different uses=3D3B My students and I wade=
d =3D
in and dug 45 gallons of silt clay muck from the Rio Verde and kids sculpte=
=3D
d 3D faces and forms on the trunks of trees in the park at the annual Verde=
=3D
River Days. The clay art work lasted several days and then the rains was=
=3D
hed the trees and slaked the muck back into the soil of the park. No cleanu=
=3D
p=3D2C no lasting mess=3D2C everyone happy.
=3D20
Several of the college students then incorporated some of the muck into the=
=3D
ir sculptural body and surface treatments with varied and interesting resul=
=3D
ts.
=3D20
David Woof....Clarkdale=3D2C AZ......Sending love to all...while considerin=
g =3D
who has been "naughty or nice" (those who know me intimately know that I ha=
=3D
ve special clout with Santa) and reaffirming my choice to prefer to regret =
=3D
things I have done rather than to regret things I could have and didn't.
=3D20
________________________________________________________________________
5a. Re: cone 5/6 glazes
Posted by: "Steve Slatin" claystevslat@YAHOO.COM=3D20
Date: Mon Dec 13=3D2C 2010 5:55 pm ((PST))
=3D20
Couple of points here -- first=3D2C there are plenty of
cone 6 clays. Laguna doesn't make them=3D2C so if you
insist on the "cone 6" label=3D2C go to another manufacturer.
=3D20
Second=3D2C all clays 'work' (to the extent that they do work
at all) within a range -- Laguna's ^5 clays all seem to
work OK at ^6.
=3D20
Third=3D2C some clays marked ^5 (or ^6 or ^10) really do better
at ^6. B-Mix ^5=3D2C for example=3D2C tests a little too absorbent
for my taste at ^5. It's actually better at ^6. My
studio mates like it=3D2C I don't=3D2C particularly. No big deal.
=3D20
It's confusing=3D2C but there's no dictatorial standard for
what ^5 or ^6 even means -- Orton and Seger are slightly
different -- and different kiln manufacturers obtain their
heat work with different firing ramps (as do different
potters).=3D20
=3D20
=3D
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