search  current discussion  categories  techniques - throwing 

good throwing clay

updated mon 29 sep 03

 

mel jacobson on wed 24 sep 03


throwing clay.

when i make porcelain, or white stoneware, i sacrifice
pure white, and translucency. i am concerned that the
clay body throws well. and i love the toughness of the
clay body.

i add 25 percent stoneware clay to my 25x4 porcelain;
that is china, silica, fels, ball. (the old alfred porc.)
it would be considered a `dirty` white stoneware, with
lots of flux.

i also add a bit of iron sand and fine grog.
this gives me a speckled white to gray clay body.
wonderful for copper red, temmoku, or a celedon
glaze.

if as craig martell prefers, a pure white, translucent
body....you must age the clay for months, learn to
throw with skill and be very patient with drying and
storing. this can be very easily learned. it is just
different than stoneware. earthenware throwing will
have its own characteristics. and they must be controlled
as well. i find soft earthenware and porcelain the most
difficult to control on the wheel. a groged, aged, stoneware
with a good percent of ball clay will throw as well as anything
in the world. add a bit of sand as warren mackenzie does, and it
will dry without warping or cracking. even in the sun and
wind.

what we are considering here is that the potter is in control
of the clay body. if you just order anything from the catalog,
well you are at the mercy of the dealer. and, you will never
find out what is in the body. that is always a trade secret.
i do not like that method, therefore i have to work at making
clay that i love. it is just part of the process. a pug mill
becomes your best friend.
and, if the clay is a bit too firm, add a cup of water and run it
through some more. ( i do love my walker.)

if you want unique, interesting pots, that do not look like
the rest of the world, control your clay body. and, as you all
know, the glaze is controlled by the clay body.
mel

From:
Minnetonka, Minnesota, U.S.A.
web site: my.pclink.com/~melpots
or try: http://www.pclink.com/melpots
new/ http://www.rid-a-tick.com

David Beumee on wed 24 sep 03


Mel is right that potters are at the mercy of the manufacturer if they just
order out of the catalog and hope for the best, but you have to start
somewhere, and Craig is right that good quality porcelain clay is becoming
commercially available.Try as many prepared porcelains as you possibly can,
and when you find one that works for you, stick with it. Eventually your
glazes will sort themselves out according to the look you want, and you can
work on the best glazes to fit that particular clay body recipe. It may well
be true that commercially prepared, "dry mixed" porcelain needs months to age
properly, but by that time it may also be too stiff to use.
One little tip I can offer about throwing porcelain, particularly vertical
forms: I wet the inside of the cylinder only, and use the cream from the
previous pull to lubricate the outside of the pot. It helps from allowing the
cylinder to absorb too much water, a problem with (porcelain) clay that
absorbs water very quickly, contributing to collapse.

David Beumee
> throwing clay.
>
> when i make porcelain, or white stoneware, i sacrifice
> pure white, and translucency. i am concerned that the
> clay body throws well. and i love the toughness of the
> clay body.
>
> i add 25 percent stoneware clay to my 25x4 porcelain;
> that is china, silica, fels, ball. (the old alfred porc.)
> it would be considered a `dirty` white stoneware, with
> lots of flux.
>
> i also add a bit of iron sand and fine grog.
> this gives me a speckled white to gray clay body.
> wonderful for copper red, temmoku, or a celedon
> glaze.
>
> if as craig martell prefers, a pure white, translucent
> body....you must age the clay for months, learn to
> throw with skill and be very patient with drying and
> storing. this can be very easily learned. it is just
> different than stoneware. earthenware throwing will
> have its own characteristics. and they must be controlled
> as well. i find soft earthenware and porcelain the most
> difficult to control on the wheel. a groged, aged, stoneware
> with a good percent of ball clay will throw as well as anything
> in the world. add a bit of sand as warren mackenzie does, and it
> will dry without warping or cracking. even in the sun and
> wind.
>
> what we are considering here is that the potter is in control
> of the clay body. if you just order anything from the catalog,
> well you are at the mercy of the dealer. and, you will never
> find out what is in the body. that is always a trade secret.
> i do not like that method, therefore i have to work at making
> clay that i love. it is just part of the process. a pug mill
> becomes your best friend.
> and, if the clay is a bit too firm, add a cup of water and run it
> through some more. ( i do love my walker.)
>
> if you want unique, interesting pots, that do not look like
> the rest of the world, control your clay body. and, as you all
> know, the glaze is controlled by the clay body.
> mel
>
> From:
> Minnetonka, Minnesota, U.S.A.
> web site: my.pclink.com/~melpots
> or try: http://www.pclink.com/melpots
> new/ http://www.rid-a-tick.com
>
> ______________________________________________________________________________
> 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 melpots@pclink.com.

Susan Setley on wed 24 sep 03


In a message dated 9/24/03 1:26:34 PM, claybuds@ATT.NET writes:

<< It may well
be true that commercially prepared, "dry mixed" porcelain needs months to age
properly, but by that time it may also be too stiff to use. >>


On the other hand, it's not hard to rehydrate it. I am going to try to buy
clay ahead of time from now on. The older porcelain I used last week let me do
things I never was able to to before.

John Rodgers on thu 25 sep 03


Mayor Mel.

I take it that the Alfred claybody you have spoken of is at least a
Cone 10 clay body.

Can it be modified to a Cone 6? If so, what change would you recommend
to achieve this?

Although my electric kiln is capable of Cone 10, I prefer not to go that
hot, and use Cone 6 mostly.

BTW .... congrats on the weight loss. Atkins worked/works for me too
...... 85 lbs so far.

Thanks,

Regards,

John Rodgers
Birmingham, AL

mel jacobson wrote:

> throwing clay.
>
> when i make porcelain, or white stoneware, i sacrifice
> pure white, and translucency. i am concerned that the
> clay body throws well. and i love the toughness of the
> clay body.
>
> i add 25 percent stoneware clay to my 25x4 porcelain;
> that is china, silica, fels, ball. (the old alfred porc.)
> it would be considered a `dirty` white stoneware, with
> lots of flux.
>
> i also add a bit of iron sand and fine grog.
> this gives me a speckled white to gray clay body.
> wonderful for copper red, temmoku, or a celedon
> glaze.
>
> if as craig martell prefers, a pure white, translucent
> body....you must age the clay for months, learn to
> throw with skill and be very patient with drying and
> storing. this can be very easily learned. it is just
> different than stoneware. earthenware throwing will
> have its own characteristics. and they must be controlled
> as well. i find soft earthenware and porcelain the most
> difficult to control on the wheel. a groged, aged, stoneware
> with a good percent of ball clay will throw as well as anything
> in the world. add a bit of sand as warren mackenzie does, and it
> will dry without warping or cracking. even in the sun and
> wind.
>
> what we are considering here is that the potter is in control
> of the clay body. if you just order anything from the catalog,
> well you are at the mercy of the dealer. and, you will never
> find out what is in the body. that is always a trade secret.
> i do not like that method, therefore i have to work at making
> clay that i love. it is just part of the process. a pug mill
> becomes your best friend.
> and, if the clay is a bit too firm, add a cup of water and run it
> through some more. ( i do love my walker.)
>
> if you want unique, interesting pots, that do not look like
> the rest of the world, control your clay body. and, as you all
> know, the glaze is controlled by the clay body.
> mel
>
> From:
> Minnetonka, Minnesota, U.S.A.
> web site: my.pclink.com/~melpots
> or try: http://www.pclink.com/melpots
> new/ http://www.rid-a-tick.com
>
> ______________________________________________________________________________
>
> 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
> melpots@pclink.com.
>

David Beumee on fri 26 sep 03


> On the other hand, it's not hard to rehydrate it. I am going to try to buy
> clay ahead of time from now on. The older porcelain I used last week let me
do things I never was able to to before.

Talking about being able to do things you couldn't do before, you might
consider the time spent rehydrating your clay versus wet mixing it yourself to
begin with. Not only will it throw like nothing you've ever used before,
double bagged it will stay moist for years.

David Beumee
Earth Alchemy Pottery
Lafayette, CO
> In a message dated 9/24/03 1:26:34 PM, claybuds@ATT.NET writes:
>
> << It may well
> be true that commercially prepared, "dry mixed" porcelain needs months to age
> properly, but by that time it may also be too stiff to use. >>
>
>
> On the other hand, it's not hard to rehydrate it. I am going to try to buy
> clay ahead of time from now on. The older porcelain I used last week let me do
> things I never was able to to before.
>
> ______________________________________________________________________________
> 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 melpots@pclink.com.

Susan Setley on fri 26 sep 03


In a message dated 9/26/03 11:11:57 AM, claybuds@att.net writes:

<< > On the other hand, it's not hard to rehydrate it. I am going to try to
buy
> clay ahead of time from now on. The older porcelain I used last week let me
do things I never was able to to before.

Talking about being able to do things you couldn't do before, you might
consider the time spent rehydrating your clay versus wet mixing it yourself
to
begin with. Not only will it throw like nothing you've ever used before,
double bagged it will stay moist for years.

David Beumee >>

David, that assumes that I have the facilities to do that. :) I am an amateur
potter who uses a public studio. We don't have facilities to mix clay. In
addition, the price of our clay includes the costs incurred by them for bisquing,
glazing and firing. It's a great way to learn but mixing my own clay isn't an
option.

No doubt someone here can benefit from your advice, however. The clay we can
buy is already of pretty good quality, easy to work with, dependable for
firing and compatible with just about any glaze anyone has tried, but I was amazed
at what reclaiming and aging did for it.

Susan Setley on fri 26 sep 03


Thanks, David, but making my own clay isn't an option.

Craig Martell on fri 26 sep 03


mel commented:
>if as craig martell prefers, a pure white, translucent
>body....you must age the clay for months, learn to
>throw with skill and be very patient with drying and
>storing.

Say what?

Let's not get too excited about that pristine stuff mel. :^) Actually,
the majority of my work is done with Tom Turner's body which is a domestic
porcelain using, tile #6 kaolin, kaopaque 20, and just a twinge of OM4
ball. It's white enough alright and a stellar throwing body, but not
totally fused and translucent. I mix it real wet in the stainless steel
dough mixer, age it for about two months, run it thru the pugmill and then
I get to work. 6 months aging is about right but 2 months is fine. With
any of these bodies it's important to mix as wet as possible to hydrate the
clays thoroughly and that speeds the aging which is mainly the complete
slaking and hydrating of the clays. Tom used a blunger and filter press to
mix this body and said that you could throw it right out of the press and
pug. Nice stuff. That's the best way to mix any clay but if you do a lot
of clay you need some room and equipment if you choose to blunge.

The reason I'm working with the really white primary kaolin bodies is the
blue celadon glazes. They are really beautiful on translucent bodies with
very very low titanium. US china clays are a bit high in TiO2. They
average about 1.5% and that's enough to "grey" the blues. John Britt is
the guy who pointed this out to me sometime back. I wasn't paying
attention but I am now. Thanks John! The lowest TiO2 bodies come from the
kaolin deposits in Cornwall, SW part of England. My present experiments
are being done with ECC Standard Porcelain which is a very white kaolin and
is similar to Grolleg. I think it throws and turns better though. It has
some Sericite present too which helps with fusion and translucency.

regards, Craig Martell Hopewell, Oregon

wayneinkeywest on sat 27 sep 03


Craig:
If your Turner's body is the same mud that Miami Clay is selling (which is
what I use) try aging it for a couple three years in plastic. Let it get
good and green
and then try it. Amazing mud!

Wayne in Key West


> Let's not get too excited about that pristine stuff mel. :^) Actually,
> the majority of my work is done with Tom Turner's body which is a domestic
> porcelain using, tile #6 kaolin, kaopaque 20, and just a twinge of OM4
> ball. It's white enough alright and a stellar throwing body, but not
> totally fused and translucent

Craig Martell on sun 28 sep 03


Wayne commented:
>If your Turner's body is the same mud that Miami Clay is selling (which is
>what I use) try aging it for a couple three years in plastic. Let it get
>good and green and then try it. Amazing mud!

Hello Wayne:

I have no idea what Miami Clay is mixing as Turner Porcelain but it could
be the same body. Tom has been very generous with that recipe.

I wish I could age the clay for at least a year or so but I need it for
pots and it gets used up. Maybe I'll set aside a bag or two and put a date
on it so I'll know how long it's aged. I usually mix at least a ton at a
time, sometimes more and that's a fairly large capital investment to sit on
for three years. I know, the "bottom line" mucks everything up!!

regards, Craig Martell Hopewell, Oregon

wayneinkeywest on sun 28 sep 03


> Hello Wayne:
>
> I have no idea what Miami Clay is mixing as Turner Porcelain but it could
> be the same body. Tom has been very generous with that recipe.
>
> I wish I could age the clay for at least a year or so but I need it for
> pots and it gets used up. Maybe I'll set aside a bag or two and put a
date
> on it so I'll know how long it's aged. I usually mix at least a ton at a
> time, sometimes more and that's a fairly large capital investment to sit
on
> for three years. I know, the "bottom line" mucks everything up!!
>
> regards, Craig Martell Hopewell, Oregon

Craig:
LOL! You are WAY out of my league.
What I meant was about putting aside a few 25# or 50# bags
as an experiment...not a ton! It just happened with me that "life got in the
way"
and the clay sat unused for a few years. That's not the norm for me either.
Is "a ton at a time" the norm for most of the people on the list?! WOW!
I don't have the room for a ton. Maybe a half ton if I stick some of it in
bags and hang it from the ceiling! Given my luck lately, maybe I had
better not. I can see it now in the paper:
"Local amateur buries self in studio. Film at 11" :>)
Best,
Wayne Seidl