Paul Borian on thu 11 mar 10
I have been using 35 mesh Mulcoa (mullite) grog from C-E minerals for a
long time. It works fine but is a bit coarse for me - leaves sharp edges
everywhere and chunks where the trimming tool carved away at the clay.
On the positive side, my clay body is just about indestructible in the
production stage, with nearly all the pots put in the bisque kilns when
leather hard and plates, platters and such need no special care at all
and almost never crack.
=3D20
So I found out I can get 100 mesh Mulcoa and ordered some right away,
and was just wondering if anyone else has used it with or without
problems? Can anyone think of potential disadvantages to using such fine
grog? I will probably start by mixing equal parts of 35 and 100 together
and see what that does, then go to just 100 mesh.
=3D20
Any comments appreciated!
Thanks,
Paul
jonathan byler on thu 11 mar 10
My understanding is that using a graded aggregate (mulitple sizes) is
usually superior to using just one size the small particles fill in
holes between the larger ones making a stronger product.
On Mar 11, 2010, at 3:03 PM, Paul Borian wrote:
> I have been using 35 mesh Mulcoa (mullite) grog from C-E minerals
> for a
> long time. It works fine but is a bit coarse for me - leaves sharp
> edges
> everywhere and chunks where the trimming tool carved away at the clay.
>
> On the positive side, my clay body is just about indestructible in the
> production stage, with nearly all the pots put in the bisque kilns
> when
> leather hard and plates, platters and such need no special care at all
> and almost never crack.
>
>
>
> So I found out I can get 100 mesh Mulcoa and ordered some right away,
> and was just wondering if anyone else has used it with or without
> problems? Can anyone think of potential disadvantages to using such
> fine
> grog? I will probably start by mixing equal parts of 35 and 100
> together
> and see what that does, then go to just 100 mesh.
>
>
>
> Any comments appreciated!
>
> Thanks,
>
> Paul
paul gerhold on fri 12 mar 10
Paul,
I am not sure my experience is directly transferable but when I switched my
Raku body from 35 mesh Kyanite to 100 mesh the resistance to cracking went
down significantly. Pieces that had been no problem for years suddenly
started cracking in the Raku firing. When I went back to 35 mesh the
problem disappeared.
Paul
On Thu, Mar 11, 2010 at 4:03 PM, Paul Borian wrote:
> I have been using 35 mesh Mulcoa (mullite) grog from C-E minerals for a
> long time. It works fine but is a bit coarse for me - leaves sharp edges
> everywhere and chunks where the trimming tool carved away at the clay.
>
> On the positive side, my clay body is just about indestructible in the
> production stage, with nearly all the pots put in the bisque kilns when
> leather hard and plates, platters and such need no special care at all
> and almost never crack.
>
>
>
> So I found out I can get 100 mesh Mulcoa and ordered some right away,
> and was just wondering if anyone else has used it with or without
> problems? Can anyone think of potential disadvantages to using such fine
> grog? I will probably start by mixing equal parts of 35 and 100 together
> and see what that does, then go to just 100 mesh.
>
>
>
> Any comments appreciated!
>
> Thanks,
>
> Paul
>
ivor & olive lewis on sat 13 mar 10
Dear Paul Gerhold,
It would be interesting to see the microstructure of these contrasting
bodies. Do you know any geology or earth science boffins who could grind
thin samples ?
Best regards,
Ivor Lewis,
Redhill,
South Australia
paul gerhold on sat 13 mar 10
Dear Ivor,
It would have been interesting but pieces are long gone. Never have been
one to collect my own work. All experiences are of course somewhat
subjective.
Paul
On Sat, Mar 13, 2010 at 1:41 AM, ivor & olive lewis
wrote:
> Dear Paul Gerhold,
>
>
>
> It would be interesting to see the microstructure of these contrasting
> bodies. Do you know any geology or earth science boffins who could grind
> thin samples ?
>
> Best regards,
>
> Ivor Lewis,
> Redhill,
> South Australia
>
| |
|
