Kathy McDonald on tue 19 apr 05
redder in oxidation refire.
I have been following this thread with interest.
II recently began to think about some crazed copper red
pieces that have been around the studio for a while,
I believe the original cause of the crazing was a cooling problem
and was attributable to my own haste to unload a kiln that was on the
warmish side. (I know better but ........I did it anyway)
These pieces were originally fired to c 10 in fairly heavy reduction and the
glaze
was a great color but a bit spotty and crazed.
I had an order for tiles to do (fired in ekiln at c 02) and was short a few
pieces for the load
so I threw in the copper red pieces just to see. They were refired to cone
02(cone in sitter) in
an electric kiln and cooled in the normal fashion to room temp. ( PS:I
wasn't as "in a hurry")
The glaze on the copper red became a much more vibrant red almost
omaroon/bright red in some places. Also the crazing seems to be "sealed in"
under the refired glaze. It is difficult to describe but it is almost as if
one
put a sealant over a crazed raku piece. The crackle is still visible but
the surfce crazing is gone.
I looked at it under a magnifier that gemologists use.
The original glaze is Pete P's Cranberry fired to cone 10 on B mix.
I expected the copper red to reoxidize at that temp it didn't. My questions
for the glaze guru's are:
Why did the glaze get so much more red and vibrant?
Could the refire at that temp have "fixed" the surface crazing?
The color was the neetest red I've seen in a while, but I definitely don't
understand the heat
and glaze chemistry dynamics at all.
Thanks in advance to any who have feedback or opinions.
Kathy
I
--
No virus found in this outgoing message.
Checked by AVG Anti-Virus.
Version: 7.0.308 / Virus Database: 266.9.16 - Release Date: 4/18/2005
| |
|
