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porcelain reclaim

updated wed 1 sep 10

 

David Beumee on mon 30 aug 10


If you pour dried porcelain scrap into an excess of water and wait
overnight, the clay will seek its own water level. You want to pour off thi=
s
excess water and save it, because you will very likely need some of it.
Don't worry about the suspended particles on top. Drill up your slurry with
a mixer until its smooth and the lumps are gone, and try not to create a
vortex which would pull air into the mixture. If the slurry needs water, ad=
d
some and mix until you have a mixture that you can stand a pencil in. I let
this mixture stand for an additional day, then remix and screen. It's
amazing how much grit and sand etc, will be left on a 50 mesh screen. If I
have 5 gallon bucket fulls I dry the slurry to moist consistency in a serie=
s
of shallow plaster bats. If it's slurry made from a hundred pounds or more
of dried scrap, I have drying racks that work well but are much slower than
using plaster.

David Beumee
Porcelain by David Beumee
Lafayette, CO









On Mon, Aug 30, 2010 at 2:35 PM, Benjamin Deschamps <
bdeschamps.home@gmail.com> wrote:

> Hello everyone,
>
> My spouse and I are beginning pottery, and we've just gotten around to
> reclaiming some porcelain. I dried it, then crushed it into small pieces,
> then
> covered it with water and waited/stirred until it was all suspended. Afte=
r
> 48
> hours, there is a layer at the bottom of the rubbermaid, but there are
> still
> particles in suspension in the water above it (the water is opaque). I
> don't
> want to drain them out with the water because I assume that those particl=
es
> serve a useful purpose in the clay body. Is there something I can add to
> help
> those particles settle or should I just give it more time? Thanks,
>
> Benjamin
>

Michael Wendt on mon 30 aug 10


Several materials will floc clay quickly... here are three I
use:

1) Cobalt Sulfate 10 grams dissolved in 5 gallons of hot
water.
Take a few teaspoons of the solution at a time and add to
the reclaim.
You should see settling occur immediately.

2) Epsom Salts saturated solution is a strong flocculant
and settles clay quickly.

3) DRA 10 Polymer which I add to my clay body is an FDA
listed food grade additive that has very long chain
molecules (100,000 - 8,000,000 polyethylene units) and is a
listed non-ionic flocculant. It works at very low additive
levels to floc the clay and makes the clay body hugely
stronger for throwing as well as reducing both throwing drag
and drying cracking.

Regards,
Michael Wendt

Benjamin wrote:
"Hello everyone,

My spouse and I are beginning pottery, and we've just gotten
around to
reclaiming some porcelain. I dried it, then crushed it into
small pieces, then
covered it with water and waited/stirred until it was all
suspended. After 48
hours, there is a layer at the bottom of the rubbermaid, but
there are still
particles in suspension in the water above it (the water is
opaque). I don't
want to drain them out with the water because I assume that
those particles
serve a useful purpose in the clay body. Is there something
I can add to help
those particles settle or should I just give it more time?
Thanks,

Benjamin"

Benjamin Deschamps on mon 30 aug 10


Hello everyone,

My spouse and I are beginning pottery, and we've just gotten around to=3D20=
=3D

reclaiming some porcelain. I dried it, then crushed it into small pieces,=
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then=3D20
covered it with water and waited/stirred until it was all suspended. Afte=
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hours, there is a layer at the bottom of the rubbermaid, but there are st=
=3D
ill=3D20
particles in suspension in the water above it (the water is opaque). I do=
=3D
n't=3D20
want to drain them out with the water because I assume that those particl=
=3D
es=3D20
serve a useful purpose in the clay body. Is there something I can add to =
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help=3D20
those particles settle or should I just give it more time? Thanks,=3D20

Benjamin

Eleanor on tue 31 aug 10


Dear Benjamin,

Just beginning? With porcelain? Very brave. I've been making pots from
stoneware for over 50 years and have been told that throwing porcelain
is like throwing cream cheese. In fact, a friend told me that in a
clay class the teacher brought in several pounds of real cream cheese
and had the students throw with it!

Anyway, I do a lot of reclaiming (I'm not a professional potter, just
a hobbyist) so I hope the following will be useful. It works for
stoneware, it should work for porcelain.

Crushing the dry clay raises dust which is harmful to breathe. Do it
outdoors or mist the air to settle the dust or better yet, wear a
mask. Or all of the above ;-)

I add throwing water to my crushed clay, being careful to scrape up
what has settled in the bowl. I believe what settles is important as
are the particles in suspension that you asked about. All of these
were in the original clay and should be restored to the reclaim.

May I suggest that you add only enough water to wet the crushed clay.
That will produce a mass soft enough to stir without much liquid on
top. If there is liquid, let it evaporate before you deal with the mass.

I empty the stirred clay onto an absorbent slab (concrete paving
stone) and leave it there until it gets almost hard enough to wedge.
Then I cover it with a piece of plastic and let it rest a few days,
kneading it under the plastic now and then. A little more exposure to
air and it's ready to wedge and use.

The resulting clay is as good or sometimes better than the original.

I don't have a pugmill; I deal with relatively small amounts of clay.
My clay never goes down the drain. These procedures seem elaborate as
written out but the process is easy and is ongoing as I work from day
to day.

I hope this is helpful.

Eleanor Kohler
Centerport, NY





".... philosophers lay down many precepts fair in argument but not
applicable in use"

--Sir Francis Bacon

Lou Raye Nichol on tue 31 aug 10


I always said that throwing porcelain was like throwing butter.

Lou Raye

-----Original Message-----
From: Clayart [mailto:Clayart@LSV.CERAMICS.ORG] On Behalf Of David Beumee
Sent: Monday, August 30, 2010 11:14 PM
To: Clayart@LSV.CERAMICS.ORG
Subject: Re: porcelain reclaim

If you pour dried porcelain scrap into an excess of water and wait
overnight, the clay will seek its own water level. You want to pour off thi=
s
excess water and save it, because you will very likely need some of it.
Don't worry about the suspended particles on top. Drill up your slurry with
a mixer until its smooth and the lumps are gone, and try not to create a
vortex which would pull air into the mixture. If the slurry needs water, ad=
d
some and mix until you have a mixture that you can stand a pencil in. I let
this mixture stand for an additional day, then remix and screen. It's
amazing how much grit and sand etc, will be left on a 50 mesh screen. If I
have 5 gallon bucket fulls I dry the slurry to moist consistency in a serie=
s
of shallow plaster bats. If it's slurry made from a hundred pounds or more
of dried scrap, I have drying racks that work well but are much slower than
using plaster.

David Beumee
Porcelain by David Beumee
Lafayette, CO









On Mon, Aug 30, 2010 at 2:35 PM, Benjamin Deschamps <
bdeschamps.home@gmail.com> wrote:

> Hello everyone,
>
> My spouse and I are beginning pottery, and we've just gotten around to
> reclaiming some porcelain. I dried it, then crushed it into small pieces,
> then
> covered it with water and waited/stirred until it was all suspended. Afte=
r
> 48
> hours, there is a layer at the bottom of the rubbermaid, but there are
> still
> particles in suspension in the water above it (the water is opaque). I
> don't
> want to drain them out with the water because I assume that those
particles
> serve a useful purpose in the clay body. Is there something I can add to
> help
> those particles settle or should I just give it more time? Thanks,
>
> Benjamin
>

John Rodgers on tue 31 aug 10


Build yourself a frame of two by fours. Make it two foot by two foot
or by four get or by eight feet. Add legs of 2x4 on the outside of the
frame to make a table about 28 inches high. Across the bottom of the
frame fasten galvanized chicken wire. Get a piece of denim material and
cover the chicken wire inside and up over the sides of the frame. Now
you are ready. Mix your reclaim clay into a a very wet slurry or even
slip and pour it onto the denim in the box. The water will drain away
and the clay will begin to dry into a clay body that at some point can
be rolled up and taken from on the fabric. It is then ready to wedge -
or run through a pug mill to further prepare for throwing.

One could further refine this by adding a sheet metal pan on the bottom
to drain the water into a bucket.

Credit for this idea goes to a very nice lady in Fairbanks, Alaska whose
name, unfortunately, I have forgotten.

John Rodgers
Chelsea, AL
On 8/30/2010 3:35 PM, Benjamin Deschamps wrote:
> Hello everyone,
>
> My spouse and I are beginning pottery, and we've just gotten around to
> reclaiming some porcelain. I dried it, then crushed it into small pieces,=
then
> covered it with water and waited/stirred until it was all suspended. Afte=
r 48
> hours, there is a layer at the bottom of the rubbermaid, but there are st=
ill
> particles in suspension in the water above it (the water is opaque). I do=
n't
> want to drain them out with the water because I assume that those particl=
es
> serve a useful purpose in the clay body. Is there something I can add to =
help
> those particles settle or should I just give it more time? Thanks,
>
> Benjamin
>
>