Dave Finkelnburg on wed 24 mar 04
Hi all!
I cannot resist butting in here...
Shinos, true Shinos, are fairly refractory, very high in alumina, glazes
that melt after a long firing. As Lee Love mentions, glazes made only from
ground feldspar.
However, mixing clay with the feldspar only makes a Shino even MORE
refractory (emphasis, not shouting). So a feldspar/clay Shino will be even
harder to melt than a straight feldspar Shino. In a wood kiln, of course,
one gains the benefit of flux from the wood ash, as vapor and direct
deposit, but that should be equal on either form of Shino.
So Lee, if your 70/30 Neph/Ball clay Shino melts for you, an
all-feldspar Shino should be even easier to melt.
Loved your teabowl, Lee, on Chris Schafale's website!
Good potting,
Dave Finkelnburg
----- Original Message -----
From: "Lee Love"
Sent: Tuesday, March 23, 2004 11:06 PM
> I use 70/30 Nep Sy/Ball Clay here in Japan and with my ball
> clay (keibushi) no soda ash is required. It is close to Kesler Shino
> which is 75 nep sy, 20 ball clay and 5% Soda Ash.
> In Japan, the shino is just feldspar, so they don't get
> carbon trapping. But even with soda ash American shinos, this can be
> controlled through application and drying.
> If you are firing for five days, you could try glazes that are
> closer to being all feldspar.
Lee Love on wed 24 mar 04
On 2004/03/24 22:44:12, Dave F. wrote:
> all-feldspar Shino should be even easier to melt.
You make a good point.
The traditional feldspar is very course so it might not melt as easily
as a combination of fine feldspar and clay. Folks I know who have used
the shino feldspar in regular glazes have had it ground finer. When Ken
Matsuzaki fires his feldspar shinos, he fires for 10 to 12 days, so the
rocks have a better chance of melting. I don't know how we might adjust
for this in America with our materials. Maybe slightly ground chicken
grit? ;-)
> Loved your teabowl, Lee, on Chris Schafale's website!
Thank you. Going to fire a bunch next week, including the 50 tea bowls
to celebrate my 50th year. Put inlay in some related to my heroes:the
mon/crest for Oishi, the leader of the 47 Ronin and also the Samurai's
flag from Seven Samurai. I want to find Sakamoto Ryoma's crest
(important figure in overthrowing the Tokugawa Shogunate) and do that too.
My next firing, I am going to concentrate the Shigaraki clay in one load
and the Mashiko clay glazed work in another firing. Today, our landlord
(who is also the owner of a construction company) brought be a bunch of
scrap
--Lee in Mashiko, Japan http://mashiko.us "It seems to me what you lose
in mystery you gain in awe" -- Francis Crick
| |
|
