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sand vs. grog

updated thu 24 mar 11

 

Lee Taylor on mon 21 mar 11


Dear Clayart,

What a wealth of information gleaned from the recent discussion on this=3D2=
0=3D

question. I have decided to scratch the sand from all of my clay recipes=
=3D
and=3D20
substitute either kyanite or mullite in its place, and just grit my teeth=
=3D
with the=3D20
grog content. Does this sound like a reasomable conclusion? Thank all o=
=3D
f you=3D20
for this awesome information (even the skirmishes around the edges of the=
=3D
=3D20
exchange were educational!).

David Beumee on mon 21 mar 11


Lee,
If you have a clay body that works for you and you want to take the time,
you might think about giving yourself an opportunity in personal choice and
find out what percentage addition of mullite feels exactly right for you.
You can begin with 3% grog addition in a 1500 gram batch, then go to 6%, 9%=
,
etc. It's also gratifying to watch how the addition of mullite grog
eliminates any warping or twisting that the body may have, as well as a
distinct reduction in shrinkage percentage.

David Beumee
Lafayette, CO











On Mon, Mar 21, 2011 at 5:30 AM, Lee Taylor wrote=
:

> Dear Clayart,
>
> What a wealth of information gleaned from the recent discussion on this
> question. I have decided to scratch the sand from all of my clay recipes
> and
> substitute either kyanite or mullite in its place, and just grit my teeth
> with the
> grog content. Does this sound like a reasomable conclusion? Thank all o=
f
> you
> for this awesome information (even the skirmishes around the edges of the
> exchange were educational!).
>

Eric Hansen on tue 22 mar 11


well the 2003 discussion of flint vs. silica was pertaining to glaze
certainly, but 100 mesh silica and/or flint used in clay body
formulation, 325 mesh being more suitable for glaze - such as:

Nelson/Shaner/Glick Porcelain cone 10 - 15
25 ball clay
25 kaolin
25 feldspar
25 flint

anyhow you look at it, that is still "sand" whether the rock is ground
and graded by nature or by man - and it represents less of an unknown
that grog, which if often a by-product of previously used refractory
materials from industry and can be contaminated with many different
things depending on prior use.

The conclusion not to use silica sand - quartz - or flint as a 100
mesh sand based on a Clayart email is premature and depends on the
variables

- h a n s e n -

On Mon, Mar 21, 2011 at 6:24 PM, David Beumee wrote=
=3D
:
> Lee,
> =3DA0If you have a clay body that works for you and you want to take the =
ti=3D
me,
> you might think about giving yourself an opportunity in personal choice a=
=3D
nd
> find out what percentage addition of mullite feels exactly right for you.
> You can begin with 3% grog addition in a 1500 gram batch, then go to 6%, =
=3D
9%,
> etc. It's also gratifying to watch how the addition of mullite grog
> eliminates any warping or twisting that the body may have, as well as a
> distinct reduction in shrinkage percentage.
>
> David Beumee
> Lafayette, CO
>
>
>
>
>
>
>
>
>
>
>
> On Mon, Mar 21, 2011 at 5:30 AM, Lee Taylor wro=
=3D
te:
>
>> Dear Clayart,
>>
>> What a wealth of information gleaned from the recent discussion on this
>> question. =3DA0I have decided to scratch the sand from all of my clay re=
ci=3D
pes
>> and
>> substitute either kyanite or mullite in its place, and just grit my teet=
=3D
h
>> with the
>> grog content. =3DA0Does this sound like a reasomable conclusion? =3DA0Th=
ank =3D
all of
>> you
>> for this awesome information (even the skirmishes around the edges of th=
=3D
e
>> exchange were educational!).
>>
>



--=3D20
Eric Alan Hansen
Stonehouse Studio Pottery
Alexandria, Virginia
americanpotter.blogspot.com
thesuddenschool.blogspot.com
hansencookbook.blogspot.com
"Simplify, simplify, simplify" - Thoreau