© Duncan Shearer, 2005 Practical Glaze Course 5

Material Triaxial Testing

Aim:
1. To explore the use of a three way mix for discovering new glazes.
2. Understand the maths of three way ratios.
3. To better understand the ratios of the major glaze constituents: fluxes, stabilisers, glass formers.

Method:
The 2 attached sheets detail how the triaxial graph is laid out and how to mix the various glazes together.
1. Make up the 3 glazes as per the schedule using the batch amounts. The percentage recipe is needed to understand the various ratios of materials. They must all be made up to identical volumes of glaze.
2. You will need to have 18 separate pots that the main 3 glazes will be divided into.
3. Lay out your glazes and mixing pots according to the graph, label each pot with MTT, then the glazes used, then its number and also label each of the test tiles with the same reference number.
4. Using either a syringe or measuring spoons divide up glaze A into all the cups using the schedule to determine amounts. It is important to always stir the glaze before removing any to insure an even consistency.
5. Now divide up glaze B and C in the same manner. Each mixing pot should have the same volume of glaze in it.
6. Stir each cup just before you dip a test tile into the mixture.

Analysis:
Lay out the test tiles into the same triangle pattern as the graph. The same sheet that you used to make up the tests also has a breakdown of what the recipe is for each tile. Use this in conjunction with the 'Test Glaze Sheet' to note the following:
1. The trends across the group, for instance, changes in opacity and colour response.
2. Note the qualities each corner exhibits and the way it is modifies as it progressively mixes with the other glazes.
3. The maths used to derive the glazes for each number of the graph are very similar to the maths used in Material Line Blends but this time you need to use the proportions of all three glazes added together.

Summary:
Triaxial testing can quickly pinpoint areas of interest and to see the effects of each material, both in isolation and in various combinations. Triaxial testing can be used to trial various flux combinations with great accuracy, or test a substitute material.
Glaze G % Batch = 600g Glaze H % Batch = 600g Glaze I % Batch = 600g
Potash Feld 40 240 Potash Feld 40 240 Potash Feld 40 240
China Clay 5 30 China Clay 25 150 China Clay 3 18
Whiting 40 240 Whiting 13 78 Whiting 17 102
Silica 15 90 Silica 22 132 Silica 40 240
Tile G ml H ml I ml Potash Feld China Clay Whiting Silica
1 100 40 5 40 15
2 80 20 40 9 34.6 16.4
3 80 20 40 4.6 35.4 20
4 60 40 40 13 29.2 17.8
5 60 20 20 40 8.6 30 21.4
6 60 40 40 4.2 30.8 25
7 40 60 40 17 23.8 19.2
8 40 40 20 40 12.6 24.6 22.8
9 40 20 40 40 8.2 25.4 26.4
10 40 60 40 3.8 26.2 30
11 20 80 40 21 18.4 20.6
12 20 60 20 40 16.6 19.2 24.2
13 20 40 40 40 12.2 20 27.8
14 20 20 60 40 7.8 20.8 31.4
15 20 80 40 3.4 21.6 35
16 100 40 25 13 22
17 80 20 40 20.6 13.8 25.6
18 60 40 40 16.2 14.6 29.2
19 40 60 40 11.8 15.4 32.8
20 20 80 40 7.4 16.2 36.4
21 100 40 3 17 40
MIX 0.33 0.33 0.33 39.96 10.989 23.31 25.641










Glaze M % Batch = 600g Glaze N % Batch = 600g Glaze O % Batch = 600g
Soda Feld 60 360 Soda Feld 30 180 Soda Feld 35 210
China Clay 10 60 China Clay 15 90 China Clay 12 72
Talc 15 90 Zinc Oxide 13 78
Whiting 10 60 Whiting 15 90 Whiting 15 90
Silica 20 120 Silica 25 150 Silica 25 150
Copper Carb 2 12 Copper Carb 2 12 Copper Carb 2 12
Tile M ml N ml O ml Soda Feld China Clay Whiting Zinc Oxide Talc Silica
1 100 60 10 10 0 0 20
2 80 20 54 11 11 0 3 21
3 80 20 55 10.4 11 2.6 0 21
4 60 40 48 12 12 0 6 22
5 60 20 20 49 11.4 12 2.6 3 22
6 60 40 50 10.8 12 5.2 0 22
7 40 60 42 13 13 0 9 23
8 40 40 20 43 12.4 13 2.6 6 23
9 40 20 40 44 11.8 13 5.2 3 23
10 40 60 45 11.2 13 7.8 0 23
11 20 80 36 14 14 0 12 24
12 20 60 20 37 13.4 14 2.6 9 24
13 20 40 40 38 12.8 14 5.2 6 24
14 20 20 60 39 12.2 14 7.8 3 24
15 20 80 40 11.6 14 10.4 0 24
16 100 30 15 15 0 15 25
17 80 20 31 14.4 15 2.6 12 25
18 60 40 32 13.8 15 5.2 9 25
19 40 60 33 13.2 15 7.8 6 25
20 20 80 34 12.6 15 10.4 3 25
21 100 35 12 15 13 0 25
MIX 0.33 0.33 0.33 41.625 12.321 13.32 4.329 4.995 23.31