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kaopaque in a porcelain body

updated wed 8 may 02

 

Craig Martell on wed 1 may 02


Hi:

I use Tom Turner's body with tile 6 and Kaopaque.

If you want to make a translucent body, Grolleg is the clay that will give
you translucency. Kaopaque 20 and tile 6 don't encourage
translucency. Grolleg isn't a real plastic, workable kaolin and neither is
Kaopaque. Tile 6 is the more plastic of the three. If you blend
carefully, using a 2:1 ratio with tile 6 and Kaopaque and leaning heavily
toward Grolleg as the major clay in the mix, you might make a good workable
translucent body.

Kaopaque is very white and also very non plastic due to the delamination
process. The kaolin plates are separated thru centrifugal force to get rid
of Leucoxene, and iron bearing material. I think the remaining whiter
kaolin is then air floated and ready for bagging and shipping. That's the
real short version of what goes on. No need to put anyone to sleep.

regards, Craig Martell in Oregon

Peter Coates on thu 2 may 02


Hey Craig

I'm curious... why use Kaopaque 20 in the Tom Turner Porcelain Body? why not
EPK or some other plastic kaolin?

Pete in Oklahoma

----- Original Message -----
From: "Craig Martell"
To:
Sent: Wednesday, May 01, 2002 10:42 PM
Subject: Re: Kaopaque in a porcelain body


> Hi:
>
> I use Tom Turner's body with tile 6 and Kaopaque.
>
> If you want to make a translucent body, Grolleg is the clay that will give
> you translucency. Kaopaque 20 and tile 6 don't encourage
> translucency. Grolleg isn't a real plastic, workable kaolin and neither
is
> Kaopaque. Tile 6 is the more plastic of the three. If you blend
> carefully, using a 2:1 ratio with tile 6 and Kaopaque and leaning heavily
> toward Grolleg as the major clay in the mix, you might make a good
workable
> translucent body.
>
> Kaopaque is very white and also very non plastic due to the delamination
> process. The kaolin plates are separated thru centrifugal force to get
rid
> of Leucoxene, and iron bearing material. I think the remaining whiter
> kaolin is then air floated and ready for bagging and shipping. That's the
> real short version of what goes on. No need to put anyone to sleep.
>
> regards, Craig Martell in Oregon
>
>
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Craig Martell on fri 3 may 02


Pete axed:
>I'm curious... why use Kaopaque 20 in the Tom Turner Porcelain Body? why
not
>EPK or some other plastic kaolin?

Hi Pete:

Kaopaque is whiter than epk and the tile 6, kaopaque body is nice and
white. Not as white as a grolleg body but pretty good and it throws better
than any epk bodies I've ever tried. Dries better without warping too.

regards, Craig Martell in Oregon

Ron Roy on tue 7 may 02


We test fire all the kaloins we use - EPK is the most plastic and the
whitest of all - including tile 6, grolleg, and pioneer.

I have never fired Kaopaque so I don't have numbers on that one - I know it
is very white - but........ it has it's share of TiO2 - which is common for
NA kaolins.

TiO2 is not good for transluncy so keep it to a minimum - the Kaolins from
England - like Grolleg have little TiO2 and that is why they are used so
often for translucent porcelains.

Iron is a contaminate of all clays - the whiter the clay the less iron - so
choosing clays and materials with the least iron becomes the way to go.

RR

Ron Roy
RR #4
15084 Little Lake Road
Brighton
Ontario
Canada - K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513