pdp1@EARTHLINK.NET on wed 14 mar 12
Well, you can get it to about as thin as a Light Bulb if you are
careful...gotta Trim bone dry to do it of course.
Then, work out how to Fire it so it behaves alright without slumping...
----- Original Message -----
From: "Ben Morrison"
> To thin to support itself usually.
>
>
> ________________________________
> From: Robert Harris
> To: Clayart@LSV.CERAMICS.ORG
> Sent: Wednesday, March 14, 2012 11:53 AM
> Subject: Re: Porcelain - 'translucent when thin'??
>
> Thanks Nathaniel - actually when I asked "What does translucent when
> thin" mean, I meant how thin is thin, not what is translucent. Sorry
> about the confusion! Should have defined "it" more clearly!
Elisabeth Maurland on wed 14 mar 12
Hi Robert,
I have always found it easy to throw porcelain. It's a lot more elastic =3D
than the stoneware I'm used to, so I can do a lot more with it. But that =
=3D
is when it is fresh out of the bag. When I try to recycle it, it loses =3D
its elasticity and becomes short, and that is the reason I don't use it =3D
regularly.
I don't specifically aim for translucency when I use it, because I =3D
decorate my pots with colorful slips, so I can't tell you much about =3D
that. Besides, the porcelain I use now is cone 6, while the porcelain I =3D
used in grad school was cone 10-12 (Grolleg). I got that translucent. I =3D
do throw pretty thin.
Porcelain has "good memory". Any dent or misshapenness, even if you =3D
straighten it, will show up again in the firing.
Elisabeth
On Mar 14, 2012, at 8:08 AM, Robert Harris wrote:
> I'm currently thinking of switching to porcelain. Since my glazes are
> dark, but translucent, I am really looking for the translucent quality
> that a good grolleg imparts, rather than the whiteness of a titanium
> bearing US kaolin.
>=3D20
> Currently I am trying out Turner's Porcelain, and Coleman Porcelain
> (in theory the most recent iteration of each), which both claim to be
> 'translucent when thin'. Does anyone have any experience as to what
> this means in practice.
>=3D20
> For mugs and bowls and so on, the Turner's does not seem to be hugely
> different to throw than the stoneware, I haven't tried the Coleman's
> yet, nor have I tried any large forms. In stoneware, I'd say my bowls
> are between 1/8" and 3/16" (3-4mm) thick, slightly thinner with mugs.
> While I can probably throw thinner (and perhaps porcelain will be more
> receptive to it), I am wondering about warping.and deformation.
>=3D20
> So any comments about how thin I should aim for, and specific tips
> about how (not) to throw porcelain, to minimise warping and
> deformation?
>=3D20
> Thanks.
>=3D20
> --
> ----------------------------------------------------------
Elisabeth=3D20
www.elisabethmaurland.com
Robert Harris on wed 14 mar 12
I'm currently thinking of switching to porcelain. Since my glazes are
dark, but translucent, I am really looking for the translucent quality
that a good grolleg imparts, rather than the whiteness of a titanium
bearing US kaolin.
Currently I am trying out Turner's Porcelain, and Coleman Porcelain
(in theory the most recent iteration of each), which both claim to be
'translucent when thin'. Does anyone have any experience as to what
this means in practice.
For mugs and bowls and so on, the Turner's does not seem to be hugely
different to throw than the stoneware, I haven't tried the Coleman's
yet, nor have I tried any large forms. In stoneware, I'd say my bowls
are between 1/8" and 3/16" (3-4mm) thick, slightly thinner with mugs.
While I can probably throw thinner (and perhaps porcelain will be more
receptive to it), I am wondering about warping.and deformation.
So any comments about how thin I should aim for, and specific tips
about how (not) to throw porcelain, to minimise warping and
deformation?
Thanks.
--
----------------------------------------------------------
Porcelain Forest on wed 14 mar 12
>
> On Wed, Mar 14, 2012 at 6:08 AM, Robert Harris w=
rote:
>
>> I'm currently thinking of switching to porcelain. Since my glazes are
>> dark, but translucent, I am really looking for the translucent quality
>> that a good grolleg imparts, rather than the whiteness of a titanium
>> bearing US kaolin.
>>
>> Currently I am trying out Turner's Porcelain, and Coleman Porcelain
>> (in theory the most recent iteration of each), which both claim to be
>> 'translucent when thin'. Does anyone have any experience as to what
>> this means in practice.
>>
>
> Oh yes, I work mostly in porcelain and when they say translucent, althoug=
h
> I haven't used these particular bodies, they mean that light transmits
> through them. Hold any decent porcelain piece of ware up to the light
> (assuming the glazes used aren't all opaque) and you will be able the see
> that light through the piece. The best and IMHO wierdest body is Southern
> Ice which is a really cool (as in color temperature) white.
>
> This is is a
> really good illustration.
>
>
>> For mugs and bowls and so on, the Turner's does not seem to be hugely
>> different to throw than the stoneware, I haven't tried the Coleman's
>> yet, nor have I tried any large forms. In stoneware, I'd say my bowls
>> are between 1/8" and 3/16" (3-4mm) thick, slightly thinner with mugs.
>> While I can probably throw thinner (and perhaps porcelain will be more
>> receptive to it), I am wondering about warping.and deformation.
>
>
> Porcelain typically shrinks anywhere from 12 to 15 per cent or higher (I
> made one that had shrinkage of 18% once), so that is going to affect
> warping and so on. I shoot for 1/8" or thinner.
>
> So any comments about how thin I should aim for, and specific tips
>> about how (not) to throw porcelain, to minimise warping and
>> deformation?
>>
>
> I haven't thrown porcelain so I can't tell you anything on that.
>
> Best,
>
> Nathaniel
>
>
Robert Harris on wed 14 mar 12
Thanks Nathaniel - actually when I asked "What does translucent when
thin" mean, I meant how thin is thin, not what is translucent. Sorry
about the confusion! Should have defined "it" more clearly!
Patty Kaliher on wed 14 mar 12
I know one Chinese master potter who throws translucent pieces. Actually,
he trims translucent pieces. Others carve the pieces or water etch the
greenware until thin enough to be translucent. Really translucent is 2-3 m=
m
thick. It seems to me that porcelain cannot be thrown thin enough to be
translucent as it will not hold up when wet and that thin. But when leathe=
r
hard the piece can be trimmed or carved to be thin and translucent. A lot
or translucent porcelain is made using a mold of some kind.
Patty Kaliher
-----Original Message-----
From: Clayart [mailto:Clayart@LSV.CERAMICS.ORG] On Behalf Of Robert Harris
Sent: Wednesday, March 14, 2012 8:54 AM
To: Clayart@LSV.CERAMICS.ORG
Subject: Re: Porcelain - 'translucent when thin'??
Thanks Nathaniel - actually when I asked "What does translucent when thin"
mean, I meant how thin is thin, not what is translucent. Sorry about the
confusion! Should have defined "it" more clearly!
-----
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Ben Morrison on wed 14 mar 12
To thin to support itself usually.
________________________________
From: Robert Harris
To: Clayart@LSV.CERAMICS.ORG
Sent: Wednesday, March 14, 2012 11:53 AM
Subject: Re: Porcelain - 'translucent when thin'??
Thanks Nathaniel - actually when I asked "What does translucent when
thin" mean, I meant how thin is thin, not what is translucent. Sorry
about the confusion! Should have defined "it" more clearly!
Clay art on thu 15 mar 12
Robert, I throw thin, on a good day 2-3 mm thick. Depending on what I am
making, I will trim further . There is nothing wrong with throwing thicker
and then trim thin, except that porcelain is already a "slow" clay and ever=
y
step consumes time.
The clay has a character that demands special attention as it constantly
change through every step. These days there are easier throwing porcelain
bodies on the market, but it does not take the "diva" out of it.
I did a study of cone 6 bodies some years back for PMI
http://ceramicartsdaily.org/free-gifts/successful-tips-for-buying-and-using=
-
pottery-clay-how-to-select-the-right-clay-estimate-your-clay-needs-and-test=
-
clays-for-better-results/
I also wrote this article
http://ceramicartsdaily.org/education/ceramic-art-lesson-plan-translucent-p=
o
rcelain/?floater=3D99 Although I changed some of my ways since the time I
wrote this article, there are very important pointers in there that I stil=
l
follow.
Of cause carving, incising and water etching help thinning the clay as well=
.
Question is if you really want to go that thin? Get your vision of what you
want to do before you decide on the transition to porcelain. Understand wha=
t
you will get yourself in, before you change and more than anything, make
sure you have the personality to live with porcelain ( sterile studio,
pampering every step etc). If your personality is not compatible with the
medium, you will run into "clay" disaster.
I hope this is helpful.
Antoinette Badenhorst
www.porcelainbyAntoinette.com
https://www.folkschool.org/index.php?section=3Dclass_detail&class_id=3D6018
-----Original Message-----
From: Clayart [mailto:Clayart@LSV.CERAMICS.ORG] On Behalf Of Robert Harris
Sent: Wednesday, March 14, 2012 8:09 AM
To: Clayart@LSV.CERAMICS.ORG
Subject: Porcelain - 'translucent when thin'??
I'm currently thinking of switching to porcelain. Since my glazes are dark,
but translucent, I am really looking for the translucent quality that a goo=
d
grolleg imparts, rather than the whiteness of a titanium bearing US kaolin.
Currently I am trying out Turner's Porcelain, and Coleman Porcelain (in
theory the most recent iteration of each), which both claim to be
'translucent when thin'. Does anyone have any experience as to what this
means in practice.
For mugs and bowls and so on, the Turner's does not seem to be hugely
different to throw than the stoneware, I haven't tried the Coleman's yet,
nor have I tried any large forms. In stoneware, I'd say my bowls are betwee=
n
1/8" and 3/16" (3-4mm) thick, slightly thinner with mugs.
While I can probably throw thinner (and perhaps porcelain will be more
receptive to it), I am wondering about warping.and deformation.
So any comments about how thin I should aim for, and specific tips about ho=
w
(not) to throw porcelain, to minimise warping and deformation?
Thanks.
--
----------------------------------------------------------
Paul Herman on thu 15 mar 12
Patty,
It is certainly possible to throw porcelain thin enough for
translucence, without excessive trimming of the whole piece. Using a
home mixed Grolleg body, or a nice prepared porcelain clay like
Coleman porcelain, I've done it many times. Long firings in wood kilns
tend to produce the most translucence, in my opinion. I think lots of
time above cone 9-10 encourages a lot of translucency. Proper melting
requires time, not just temperature.
Good firings,
Paul Herman
Great Basin Pottery
Doyle, California US
www.greatbasinpottery.com/
On Mar 14, 2012, at 5:42 PM, Patty Kaliher wrote:
> I know one Chinese master potter who throws translucent pieces.
> Actually,
> he trims translucent pieces. Others carve the pieces or water etch
> the
> greenware until thin enough to be translucent. Really translucent
> is 2-3 mm
> thick. It seems to me that porcelain cannot be thrown thin enough
> to be
> translucent as it will not hold up when wet and that thin. But when
> leather
> hard the piece can be trimmed or carved to be thin and translucent.
> A lot
> or translucent porcelain is made using a mold of some kind.
>
> Patty Kaliher
Hank Murrow on thu 15 mar 12
On Mar 15, 2012, at 10:31 AM, Paul Herman wrote:
> Patty,
>=3D20
> It is certainly possible to throw porcelain thin enough for
> translucence, without excessive trimming of the whole piece. Using a
> home mixed Grolleg body, or a nice prepared porcelain clay like
> Coleman porcelain, I've done it many times. Long firings in wood kilns
> tend to produce the most translucence, in my opinion. I think lots of
> time above cone 9-10 encourages a lot of translucency. Proper melting
> requires time, not just temperature.
Amen Paul!
My firings tend to go 24 hours to Cone 11 at the four o'clock position =3D
(most of that time above Cone 5), and then I also soak in oxidation for =3D
from 2 to 8 hours at 1800_1900F before closing up the kiln to cool =3D
slowly. I get great translucency providing the body and glaze have next =3D
to no Titanium in them. American kaolins have too much Ti and Fe to =3D
promote translucency. Time works wonders! despite Mel's rants on fast =3D
firing. love him anyway! I can always count my fingers through the body =3D
and I do not trim thin.
Cheers, Hank
PS: Here's and example:
Crystal Springs body made with Grolleg kaolin and glazed with my yellow.
Elisabeth Maurland on fri 16 mar 12
Hi David,
Thanks for the low-down.
I used Polar Porcelain from Minnesota Clay. It's been a while, but I =3D
don't think I had any cracking problems with it. I remember liking it a =3D
lot, except for the recycling part.=3D20
Elisabeth
On Mar 16, 2012, at 2:10 PM, david wrote:
> Hi Elisabeth and Robert.
>=3D20
> I only ever fire to cone 6, and have worked with three 'cone 6 =3D
porcelain' clay bodies. They vary in ease of throwing and translucency.
>=3D20
> Plainsman P300 is not even supposed to be translucent (according to =3D
their website) but if you throw it to 2 mm and shine a light through it =3D
you will see the light on the outside of the pot. It is very easy to =3D
work with, doesn't warp or crack much, and supports its weight both up =3D
(cylinders) and sideways (bowls). It feels oily and smooth.
>=3D20
> SPS Dove is of medium translucency, 3-4 mm and shine a light inside =3D
it, you will see light outside, and you can count your fingers if you =3D
put them between the pot and a source of light. However I find it very =3D
'limp', and it's still a challenge to make a reasonably light bowl out =3D
of it. It also chatters a lot when trimmed and even when you scrape off =3D
the slip with a metal rib. It is also the shortest of the three bodies. =3D
And cheapest. It is whiter than P300. It feels nicely gritty to the =3D
touch. It responds to your every mistake and is really easy to off =3D
centre. I throw it on a slower wheel. I actually find its medium elusive =
=3D
translucency quite alluring, sometimes more so than Frost's (see below) =3D
In Your Face translucency.
>=3D20
> Laguna Frost is extremely translucent and I have not managed to get it =
=3D
to be not translucent no matter how careless I am about thinness of =3D
throwing. I find it nice to throw, it holds its shape well as long as it =
=3D
is not too wet. It feels gummy to the touch and very smooth. It will =3D
crack if not compressed enough, or bottom too thick, and attachments =3D
tend to develop hairline cracks. It tends to chip when cut at leather =3D
hard (spouts, teapot holes, etc. It warps more than the other two, is an =
=3D
in-your-face (but warm, in ox) white, and dries (and re-wets) extremely =3D
fast leaving white dust on everything.
>=3D20
> In short you can definitely throw (cone 6) porcelain thin enough to be =
=3D
translucent and support its weight. I find the experience of working =3D
with those 3 bodies to be completely different and from what I hear it =3D
is the same with cone 10 porcelains - there is no one 'porcelain =3D
experience' but many.
>=3D20
> As for advice, none of it original or new, just good working habits - =3D
compress your bottoms when throwing, use minimal water or throw with =3D
slip, rib your walls, compress your bottoms when trimming, dry =3D
attachments evenly (more important than slowly) under cotton fabric. Dry =
=3D
pots on something movable (newspaper) rather than plastic or wood. Use =3D
sharp tools to trim and cut.
>=3D20
> --- In clayart@yahoogroups.com, Elisabeth Maurland =3D
wrote:
>>=3D20
>> Hi Robert,
>>=3D20
>> I have always found it easy to throw porcelain. It's a lot more =3D
elastic than the stoneware I'm used to, so I can do a lot more with it. =3D
But that is when it is fresh out of the bag. When I try to recycle it, =3D
it loses its elasticity and becomes short, and that is the reason I =3D
don't use it regularly.
>>=3D20
>> I don't specifically aim for translucency when I use it, because I =3D
decorate my pots with colorful slips, so I can't tell you much about =3D
that. Besides, the porcelain I use now is cone 6, while the porcelain I =3D
used in grad school was cone 10-12 (Grolleg). I got that translucent. I =3D
do throw pretty thin.
>>=3D20
>> Porcelain has "good memory". Any dent or misshapenness, even if you =3D
straighten it, will show up again in the firing.
>>=3D20
>> Elisabeth
>> On Mar 14, 2012, at 8:08 AM, Robert Harris wrote:
>>=3D20
>>> I'm currently thinking of switching to porcelain. Since my glazes =3D
are
>>> dark, but translucent, I am really looking for the translucent =3D
quality
>>> that a good grolleg imparts, rather than the whiteness of a titanium
>>> bearing US kaolin.
>>>=3D20
>>> Currently I am trying out Turner's Porcelain, and Coleman Porcelain
>>> (in theory the most recent iteration of each), which both claim to =3D
be
>>> 'translucent when thin'. Does anyone have any experience as to what
>>> this means in practice.
>>>=3D20
>>> For mugs and bowls and so on, the Turner's does not seem to be =3D
hugely
>>> different to throw than the stoneware, I haven't tried the Coleman's
>>> yet, nor have I tried any large forms. In stoneware, I'd say my =3D
bowls
>>> are between 1/8" and 3/16" (3-4mm) thick, slightly thinner with =3D
mugs.
>>> While I can probably throw thinner (and perhaps porcelain will be =3D
more
>>> receptive to it), I am wondering about warping.and deformation.
>>>=3D20
>>> So any comments about how thin I should aim for, and specific tips
>>> about how (not) to throw porcelain, to minimise warping and
>>> deformation?
>>>=3D20
>>> Thanks.
>>>=3D20
>>> --
>>> ----------------------------------------------------------
>>=3D20
>> Elisabeth
>> www.elisabethmaurland.com
>>=3D20
>=3D20
>=3D20
Elisabeth=3D20
www.elisabethmaurland.com
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