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the microwave

updated tue 10 jan 12

 

Lee on sun 8 jan 12


On Sun, Jan 8, 2012 at 4:40 PM, William & Susan Schran User
wrote:
ny help I can get on this is mucho appreciated.
>
> Just a thought - what about approaching this like industry?
> Fire the greenware to vitrification, cone 1 or where ever would create ni=
=3D
ce
> tight ware, then stilt and fire the glaze at lower temperature, so the
> entire surface is covered in glaze.

Why? At cone 1, glazes are more durable but have the same color
range as 04/05

I've glazes vitreous ware. It is a pain in the ass.

Folks are trying to fix a problem that doesn't exist. Tony is smart
enough, he will find out for himself through trial and error

--
=3DA0Lee Love in Minneapolis
http://mingeisota.blogspot.com/

=3DA0"Ta tIr na n-=3DF3g ar chul an tI=3D97tIr dlainn trina ch=3DE9ile"=3D9=
7that is, =3D
"The
land of eternal youth is behind the house, a beautiful land fluent
within itself." -- John O'Donohue

mel jacobson on sun 8 jan 12


has created a new form of
ceramic ware...`microproof`.

it is just a fact of life.

most folks use one, all the time, every
day...and they stick everything in there.

potters are going to have to become
`totally` aware of what you sell and where
it is going to be used.

labels on your ware or not.
up to you.

i am sure glad i make really vitrified, solid
work. never have had trouble...ever.
\but, it may come, so i must be prepared.
mel
it does not matter that folks in 1756 used
slip ware, low fire leaded pots...we have to know what
is going on now, today. and, know for sure.
i wish we had uranium yellow...we don't.
wishing is for fools or `tinker bell`.
from: minnetonka, mn
website: http://www.visi.com/~melpots/
clayart link: http://www.visi.com/~melpots/clayart.html

tony clennell on sun 8 jan 12


Mel: I just tried the glass of water in the micro along with some various
e-ware cups. Some are too hot to handle while others are as cool as a
cucumber.
One needs to use their brains sometimes when handling pots. You don't fill
a teapot with boiling water and then wrap your hands around the body to
pick it up. But you're right we have to be fully fledged members of the CYA
Club- Cover Your Arses Club.
Some idiot will burn themselves and you will be to blame.
I am very conscious of developing my clay first, then the slip and then the
glaze. It will get the micro treatment big time as I fully expect to have
people use the pots in the micro.
I just read if the clay gets hot there are minute air bubbles in the clay
structure. Would de-airing help? If any of the clay gurus have an answer
I'd appreciate it.
tc

On Sun, Jan 8, 2012 at 12:43 PM, mel jacobson wrote:

> has created a new form of
> ceramic ware...`microproof`.
>
> it is just a fact of life.
>
> most folks use one, all the time, every
> day...and they stick everything in there.
>
> potters are going to have to become
> `totally` aware of what you sell and where
> it is going to be used.
>
> labels on your ware or not.
> up to you.
>
> i am sure glad i make really vitrified, solid
> work. never have had trouble...ever.
> \but, it may come, so i must be prepared.
> mel
> it does not matter that folks in 1756 used
> slip ware, low fire leaded pots...we have to know what
> is going on now, today. and, know for sure.
> i wish we had uranium yellow...we don't.
> wishing is for fools or `tinker bell`.
> from: minnetonka, mn
> website: http://www.visi.com/~melpots/
> clayart link: http://www.visi.com/~melpots/clayart.html
>

John Hesselberth on sun 8 jan 12


On Jan 8, 2012, at 3:16 PM, tony clennell wrote:

> I am very conscious of developing my clay first, then the slip and =3D
then the
> glaze. It will get the micro treatment big time as I fully expect to =3D
have
> people use the pots in the micro.

Hi Tony,

Deairing will not help. Earthenware fired to normal temperatures is =3D
inherently porous or absorbent. You best bet is to fire as close to =3D
vitrification as you can and pay a lot of attention to glaze/body fit. =3D
Coating the whole pot with an engobe that is right on the edge of =3D
sticking to your shelves will help too--or glaze the bottom and fire on =3D
stilts. It is a delicate balance, but as you have observed, it can be =3D
done.

Regards,

John


"If you eat a frog first thing in the morning, that will probably be the =
=3D
worst thing you do all day." Mark Twain

John Hesselberth
john@frogpondpottery.com

tony clennell on sun 8 jan 12


thanx John I know my uncle fired his e-ware to Cone 1 and it was pretty
dense. I have added some frit to the body.
Here is the formula I will be mixing this week. Whadda ya think?
Redart 70
Redstone 10
Bell Dark 20
Frit 3124 03
Talc 05
Barium .5
Add 5% medium grog
E-ware gets enuff bad raps without me scalding someone so I am being very
careful. If I do this right it opens many doors for Clayarters that have
urban studios, like colour and want to produce a quality product for daily
use.
Any help I can get on this is mucho appreciated.
Ciao,
Tony

On Sun, Jan 8, 2012 at 4:22 PM, John Hesselberth w=
rote:

>
> On Jan 8, 2012, at 3:16 PM, tony clennell wrote:
>
> I am very conscious of developing my clay first, then the slip and then t=
he
> glaze. It will get the micro treatment big time as I fully expect to have
> people use the pots in the micro.
>
>
> Hi Tony,
>
> Deairing will not help. Earthenware fired to normal temperatures is
> inherently porous or absorbent. You best bet is to fire as close to
> vitrification as you can and pay a lot of attention to glaze/body fit.
> Coating the whole pot with an engobe that is right on the edge of stickin=
g
> to your shelves will help too--or glaze the bottom and fire on stilts. It
> is a delicate balance, but as you have observed, it can be done.
>
> Regards,
>
> John
>
>
> "If you eat a frog first thing in the morning, that will probably be the
> worst thing you do all day." Mark Twain
>
> John Hesselberth
> john@frogpondpottery.com
>
>
>
>
>


--
Tony Clennell, B.BM., B. Ed, MFA, RCA
Adjunct Professor of Ceramics- Sheridan College School of Craft and Design

http://smokieclennell.blogspot.com

WJ Seidl on sun 8 jan 12


Tony:
I'm not a scientist nor do I play one on TV, but I have done a bit of
research on this in connection with my work on the microwave drying of
greenware.
First, a segue...
Back some time ago, (I can't remember the details, but I'm sure they're
on the Net) a potter came out with a set of plates which would heat nicely
when placed in a microwave. His technique, IIRC was proprietary, which
boiled down to including a layer of high iron clay in the bottom of the
plate, surrounded top, bottom and sides by the "regular" clay body with
which he threw. The iron in the claybody transduced (?) the microwave
energy into heat, thus heating the plate and the food on it. His method
was unique in that his general claybody and the glazes he used had the
same rate of expansion and shrinkage as the high iron layer incorporated
into the bottom.
That's all I remember. You can take it from there.

In my research, I have found that higher iron clay bodies do indeed heat
more rapidly than lower iron content bodies. The trick, then, is to
make a handle clay which, while maintaining the same appearance and
properties as your body clay, has much less iron content. In that way,
your handle will heat less than the surrounding vessel, while hopefully
still remaining attached. Your glazes will have to be tested for fit on
both bodies as well.
But it does work, I know this from experience.

De-airing clay is always a good idea. Over time, we all know what
pockets of moisture (however small) in a clay body can do.
Destroy microwave ovens, for one thing....KABOOM! Luckily, there seems
to be no end of supply of small cheap used ones at yard sales.

Hope you're staying warm over there, you westerner .

Best,
Wayne Seidl

On 1/8/2012 3:16 PM, tony clennell wrote:
> Mel: I just tried the glass of water in the micro along with some various
> e-ware cups. Some are too hot to handle while others are as cool as a
> cucumber.
> One needs to use their brains sometimes when handling pots. You don't fil=
l
> a teapot with boiling water and then wrap your hands around the body to
> pick it up. But you're right we have to be fully fledged members of the C=
YA
> Club- Cover Your Arses Club.
> Some idiot will burn themselves and you will be to blame.
> I am very conscious of developing my clay first, then the slip and then t=
he
> glaze. It will get the micro treatment big time as I fully expect to have
> people use the pots in the micro.
> I just read if the clay gets hot there are minute air bubbles in the clay
> structure. Would de-airing help? If any of the clay gurus have an answer
> I'd appreciate it.
> tc

Lee on sun 8 jan 12


On Sun, Jan 8, 2012 at 2:16 PM, tony clennell wro=
=3D
te:


> I just read if the clay gets hot there are minute air bubbles in the clay
> structure. Would de-airing help? If any of the clay gurus have an answer
> I'd appreciate it.

I know cone 1 helps.

Isn't all "claystore" clay deaired?

--
=3DA0Lee Love in Minneapolis
http://mingeisota.blogspot.com/

=3DA0"Ta tIr na n-=3DF3g ar chul an tI=3D97tIr dlainn trina ch=3DE9ile"=3D9=
7that is, =3D
"The
land of eternal youth is behind the house, a beautiful land fluent
within itself." -- John O'Donohue

Lee on sun 8 jan 12


On Sun, Jan 8, 2012 at 4:05 PM, tony clennell wro=
=3D
te:
> thanx John I know my uncle fired his e-ware to Cone 1 and it was pretty
> dense. I have added some frit to the body.
>

Tony, White earthenware is hazardous at higher temps, but the
Continental Terracotta I use will fire to cone 6. I remember
seeing a group of things Continental fired for a newbie who asked for
cone 6 instead of cone 06. There didn't appear to be any bloating
or slumping. Actually, it was very dense and strong.

Of all the clays I use, including porcelain, my earthenware
at cone 1 has the best ring.

Please see Pete Pinell's article on claybodies and strength.

--
=3DA0Lee Love in Minneapolis
http://mingeisota.blogspot.com/

=3DA0"Ta tIr na n-=3DF3g ar chul an tI=3D97tIr dlainn trina ch=3DE9ile"=3D9=
7that is, =3D
"The
land of eternal youth is behind the house, a beautiful land fluent
within itself." -- John O'Donohue

William & Susan Schran User on sun 8 jan 12


On 1/8/12 5:05 PM, "tony clennell" wrote:

> E-ware gets enuff bad raps without me scalding someone so I am being very
> careful. If I do this right it opens many doors for Clayarters that have
> urban studios, like colour and want to produce a quality product for dail=
y
> use.
> Any help I can get on this is mucho appreciated.

Just a thought - what about approaching this like industry?
Fire the greenware to vitrification, cone 1 or where ever would create nice
tight ware, then stilt and fire the glaze at lower temperature, so the
entire surface is covered in glaze.

Bill

--
William "Bill" Schran
wschran@cox.net
wschran@nvcc.edu
http://www.creativecreekartisans.com

tony clennell on sun 8 jan 12


Bill and others: thanx for all the info. I got a pile of stilts with the
kiln buttttttttttttttttttttt I like the looks of red clay. I especially
like the look of red clay with terra sig on it. I don't want to stilt. I
want to show off the clay. I will try to fire as close to vitrification as
possible. I could sure use a small test kiln. tc

On Sun, Jan 8, 2012 at 5:40 PM, William & Susan Schran User t
> wrote:

> On 1/8/12 5:05 PM, "tony clennell" wrote:
>
> > E-ware gets enuff bad raps without me scalding someone so I am being ve=
ry
> > careful. If I do this right it opens many doors for Clayarters that hav=
e
> > urban studios, like colour and want to produce a quality product for
> daily
> > use.
> > Any help I can get on this is mucho appreciated.
>
> Just a thought - what about approaching this like industry?
> Fire the greenware to vitrification, cone 1 or where ever would create ni=
ce
> tight ware, then stilt and fire the glaze at lower temperature, so the
> entire surface is covered in glaze.
>
> Bill
>
> --
> William "Bill" Schran
> wschran@cox.net
> wschran@nvcc.edu
> http://www.creativecreekartisans.com
>
>
>


--
Tony Clennell, B.BM., B. Ed, MFA, RCA
Adjunct Professor of Ceramics- Sheridan College School of Craft and Design

http://smokieclennell.blogspot.com

John Hesselberth on sun 8 jan 12


On Jan 8, 2012, at 5:05 PM, tony clennell wrote:

> thanx John I know my uncle fired his e-ware to Cone 1 and it was =3D
pretty dense. I have added some frit to the body.
> Here is the formula I will be mixing this week. Whadda ya think?
> Redart 70
> Redstone 10
> Bell Dark 20
> Frit 3124 03
> Talc 05
> Barium .5
> Add 5% medium grog



Tony, clay body formulation is not my bag. I'll leave this one to Ron or =
=3D
someone else who is an expert in that area to comment on your recipe.

Regards,

John
John Hesselberth
www.frogpondpottery.com

"Man is a tool-using animal....without tools he is nothing, with tools =3D
he is all" .... Thomas Carlyle

ronroy@CA.INTER.NET on mon 9 jan 12


Hi Tony,

You will have to test each batch because red art varies so much - I
assume you will have it mixed and if that is so what do you do with
the batches that leak?

If you will be mixing your own you can test the red art before - do it
now and keep a record. Remember - once it's mixed it's hard to change
it.

Frank can send you the testing results for red art so you can see the
swings up and down.

If you are making your own samples to test remember - machine made
clay will have about 1% less absorbency.

It's easy to test for leakage - just make some cylinders and fill them
with water - place on paper and leave for 24 hours.

If you want the testing procedures we use at Tuckers let me know.

RR

Quoting tony clennell :

> thanx John I know my uncle fired his e-ware to Cone 1 and it was pretty
> dense. I have added some frit to the body.
> Here is the formula I will be mixing this week. Whadda ya think?
> Redart 70
> Redstone 10
> Bell Dark 20
> Frit 3124 03
> Talc 05
> Barium .5
> Add 5% medium grog
> E-ware gets enuff bad raps without me scalding someone so I am being very
> careful. If I do this right it opens many doors for Clayarters that have
> urban studios, like colour and want to produce a quality product for dail=
y
> use.
> Any help I can get on this is mucho appreciated.
> Ciao,
> Tony
>
> On Sun, Jan 8, 2012 at 4:22 PM, John Hesselberth
> wrote:
>
>>
>> On Jan 8, 2012, at 3:16 PM, tony clennell wrote:
>>
>> I am very conscious of developing my clay first, then the slip and then =
the
>> glaze. It will get the micro treatment big time as I fully expect to hav=
e
>> people use the pots in the micro.
>>
>>
>> Hi Tony,
>>
>> Deairing will not help. Earthenware fired to normal temperatures is
>> inherently porous or absorbent. You best bet is to fire as close to
>> vitrification as you can and pay a lot of attention to glaze/body fit.
>> Coating the whole pot with an engobe that is right on the edge of sticki=
ng
>> to your shelves will help too--or glaze the bottom and fire on stilts. I=
t
>> is a delicate balance, but as you have observed, it can be done.
>>
>> Regards,
>>
>> John
>>
>>
>> "If you eat a frog first thing in the morning, that will probably be the
>> worst thing you do all day." Mark Twain
>>
>> John Hesselberth
>> john@frogpondpottery.com
>>
>>
>>
>>
>>
>
>
> --
> Tony Clennell, B.BM., B. Ed, MFA, RCA
> Adjunct Professor of Ceramics- Sheridan College School of Craft and Desig=
n
>
> http://smokieclennell.blogspot.com
>