Kat on tue 4 nov 03
Ron:
In regards to Barry's glaze where would you say his silica alumina ratio
should be?
I adjusted his glaze to be this:
54.67 Cornwall
15.77 Dolomite
10.85 OM#4 ball clay
3.15 Wollastonite
9.99 EPK
5.57 Silica
---------------
-His past/past glaze had a expansion of 6.72 (adjusted to not craze)
-His current one, a expansion of 6.32. (from Tony's Insight)
-The one above has an expansion of
6.49, but the si:al; is 6.28 (it seems ok to me)
I kept the mgO the same as
to not change the look of his glaze. What do you think?
Kat in the Hat
kat@digitalfire.com
--------------------------
Ron Roy on wed 5 nov 03
Hi Kat,
See my further post on this - I think you did well - I kept the ration of
my revisions close and keep the MgO the same - that was smart of you.
Cornwall stone is not necessary - I think - so I did it with Custer and
G200. Less expensive and more KNaO - which raises expansion.
I raised the expansion even more - if it crazes we then know the answer is
somewhere in between.
My revisions may not look quite the same but then I would make further
adjustments if necessary.
Let me know if you have any more questions on this.
RR
>In regards to Barry's glaze where would you say his silica alumina ratio
>should be?
>I adjusted his glaze to be this:
>
>54.67 Cornwall
>15.77 Dolomite
>10.85 OM#4 ball clay
>3.15 Wollastonite
>9.99 EPK
>5.57 Silica
>---------------
>
>-His past/past glaze had a expansion of 6.72 (adjusted to not craze)
>-His current one, a expansion of 6.32. (from Tony's Insight)
>-The one above has an expansion of
>6.49, but the si:al; is 6.28 (it seems ok to me)
>I kept the mgO the same as
>to not change the look of his glaze. What do you think?
>
>Kat in the Hat
>kat@digitalfire.com
>--------------------------
>
>______________________________________________________________________________
>Send postings to clayart@lsv.ceramics.org
>
>You may look at the archives for the list or change your subscription
>settings from http://www.ceramics.org/clayart/
>
>Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513
| |
|
