Bill Merrill on thu 2 oct 08
Iron blue cone 10 glazes can have whiting in them. Check out Carlton
Ball's book, "Making Pottery Without a Wheel" There are several celadon
type glazes in the back of the book. In Val Cushing's glaze calc class
he gave limits for all sorts of glazes. Iron blue was one of them. His
handbook has all of those limits in them. His handbook that was done
years after the class I took, mirrors what he said in his lectures. I
still have my notes, listed by day and time of the lecture. The
following are Vals limits for iron blues. The list is a guide to start
developing a glaze not a specific glaze guarantee. Some of Tom
Coleman's glaze are good and they also are published.
=20
Val's limits on Iron blue base
=20
45 70 % Potash spar
0-5% Frit 3124 (boron)
0-15 Colemanite
5-20 Whiting
0-5 Lithiun Carb.
0-15 Bone ash or TCP
0-8 Magnesium Carb.
5-20 Barium Carb.=20
0-20 Strontium Carb.
0-10 Zinc
0-10 Wollstonite
0-10 Barnard Clay
20-30 Flint
2-15 EPK
2 bentonite depends on ingrediants you choose.
TOTAL BATCH 100
Add 0-5 % tin=20
0-5 ZIRCOPAX=20
IRON OXIDE IN VARIOUS SMALL AMOUNTS
=20
=20
=20
=20
=20
=20
=20
=20
=20
=20
John Britt on fri 3 oct 08
Not to go against what anyone has said, but I have glaze guarantees and
actual recipes with common materials and mixing, application and firing
instructions in my book. You don=92t need a higher potassium feldspar tha=
n
Custer and for that matter, as I show with test tiles in my book, you can
get nice blue celadons with sodium feldspars!
It will definitely save you a lot of struggle and get you some beautiful
blue celadons.
I also have a glaze chemistry class and a celadon firing class if you nee=
d
it.
Let me know if you need some help at - jbritt@main.nc.us
(For some odd reason I cannot post at this address anymore, so I have to
log in at my wife=92s email. She really doesn=92t care about Clayart post=
s.)
Or you can go to my website for my email,
John Britt
www.johnbrittpottery.com/wks.htm
www.ncclayclub.blogspot.com
| |
|
