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glaze course lesson two part two july 8 2000

hal mc whinnie on thu 6 jul 00

CAERAMIC GLAZE COURSE
LESSON TWO PART TWO

A THEORY OF LIMITS

To be able to write a molecular formula [a seger formula] for any specific
cone level there are some important guidelines, it is not just a matter of
making up some numbers in your head like I asked you to do with the homework
at the end of the first part of this lesson.

1]
For cone level
Cone 04-06 silica content 1,60 to 1.90
Cone 3-6 silica content 1.90 to 2.50
Cone 8-10 silica content 2.50 to 4.50

2] For surface quality
Gloss alumna to silica ratio 1\10 to 1\12
Satin Matt alumna to silica ratio 1/7 to1/9
Matt alumna to silica ratio 1/5 to 1/7
Dry Matt alumna to silica ratio 1/3 to 1/5
3] For amount of fluxes in the ro column [which can be no more than 1.00]
Knao .20 to .60
Cao .20 to .50
Mgo . 00 to .30
Zno . 00 to .30
Bao . 00 to .30
Lio .00 to .20
Tio .00 to .20

with these guideline we can now develop three seger formulas for different
cone levels
Cone 04
Sio2 1.70
Al2o3 0.17
Cao 0.30
Knao 0.30
Mgo 0.10
Zno 0.05
Tio 0.10
Lio 0.05
Feo 0.05
Cuo 0.05

Blue green gloss for cone 04 oxidation

Cone 3-5

Sio2 2.20
Al2o3 0.22
Cao 0.35
Knao 0.35
Mgo 0.10
Zno 0.10
Tio 0.10
A tan gloss glaze for either oxidation or reduction

Cone 8-10
Sio2 3.00
Al2o3 0.30
Cao . 40
Knao 0.40
Mgo 0.10
Zno 0.05
Tio 0.05

A tan gloss glaze for reduction

Homework

If you have access to one of the computer program you can try to convert
these three formulas to a grams batch recipe, convert in terms of percent
based on 100.

In our next lesson we shall learn to convert these by the traditional hand
method and after that we shall take a well-deserved break from the entire
math.