barn on mon 22 jun 98
It was a success. I still need to work on my application skills, but the
firing looked very
good. the second load is cooling now. I do have a problem though. I have
some pieces
that were done with a burnt buff clay body (stoneware). I have some that
were bisqued
to ^010 and some to ^04. The body has large blisters after the glaze
firing under the glaze.
The blister is present on the inside and outside of the pot so I assume
it's the claybody rather
than the glaze. The other claybodys had no problem. From my reading I
would guess this
is a gas build up under the glaze. Would a slower glaze firing take care
of this. I have shyed
away from doing a ramp/hold firing so far as I felt I did'nt need any
new variables. I was
thinking this might be taken care of by doing a slow cool down. I fired
medium speed with
a 15 minute hold. Any suggestions.
Barney
Jennifer M. Dubats on tue 23 jun 98
Barney,
I always bisque fire to 05 slowly, at least 9 hours (on D with my Cress kiln
with firemate) . I never have any problems even with the darker red iron
bodies I have tried.
Maybe a longer bisque will help you.
Sincerely,
Jenny D.
Ray Carlton on tue 23 jun 98
hi barney....sounds like bloating or over fired clay body either change to
a high fire body or change the glaze to a low fire glaze and fire
accordingly...check the firing range of the clay
good luck
At 13:03 22/06/98 EDT, you wrote:
>----------------------------Original message----------------------------
>It was a success. I still need to work on my application skills, but the
>firing looked very<<<<>>>>>>>>
cheers :) Ray Carlton
McMahons Creek Victoria Australia
Barney Adams on wed 24 jun 98
Thanks,
bloating seems the most likely. The clay body is rated ^5-^7.
I'm going to try slowing down the bisque and add a soak.
Barney
>
> ----------------------------Original message----------------------------
> hi barney....sounds like bloating or over fired clay body either change to
> a high fire body or change the glaze to a low fire glaze and fire
> accordingly...check the firing range of the clay
>
> good luck
>
>
> At 13:03 22/06/98 EDT, you wrote:
> >----------------------------Original message----------------------------
> >It was a success. I still need to work on my application skills, but the
> >firing looked very<<<<>>>>>>>>
> cheers :) Ray Carlton
>
> McMahons Creek Victoria Australia
>
>
>
Hulda Bretones on fri 26 jun 98
Hi Barn
Wish could have answered your message before.
Last week I had a similar problem in glaze firing.
The large blisters are caused by overfiring the claybody; even if it's
a stoneware claybody, as Ray Carlton said, it has a firing range that
you may check. Some stoneware claybodies support a higher temperature,
others not.
This problem is not caused by the speed firing , neither by the bisque
firing range. Don't use this claybody in this glaze firing range and
you aren't going to have this problem any more!
Hulda
From S. Paulo - Brazil
| |
|
