Cone 6 Oxidation Results Group 5
Thus far I have batched over 120+ different glazes in 300 gram batches, the formulas for which have been found from publicly available sources. After firing these tests in an electric kiln to Cone 6, I have photographed each and am making them available to potters with the accompanying formulas.
One difference with this Group 5 is that I have introduced a cooling cycle to the firing. The cycle is as follows and the firing is accompanied by a Cone 6 witness cone. After 12 consecutive firings, the witness cones are identical from firing to firing.
The firing cycle:
| Rate | Temp | Hold Time | ||
| rA1= 360 | F1 = 900 | 0 | ||
| rA2= 300 | F2 = 1800 | 0 | ||
| rA3 =200 | F3 = 2016 | 0 | ||
| rA4 = 108 | F4 = 2197 | 0.3 | ||
| rA5 = Full | F5 =1800 | 0 | ||
| rA6 =150 | F6 = 1300 | 0 | ||
| rA7 = 0000 |
To summarize, I fire at a rate of 360/hr to 900 degrees F, then at 300 degrees/ hr to 1800 degrees F, 200 degrees/hr until 2016 degrees F is reached, then 108 degrees/hour to 2197 at which time I hold it at that temperature for 30 minutes.
The kiln is shut off until a temperature of 1800 degrees F is reached and then turned on to slow the rate of cooling to 150 degrees/hr until 1300 degrees F is reached. At this point the kiln is turned off and cools naturally.
I use a Vulcan kiln controller attached to a Paragon QA11 test kiln. The combination of new elements in the Paragon and new thermocouple and controller has produced consistent heat work from one firing to the next.
Links to Cone 6 Groups 1 - 4 without controlled cooling.
Group 1
Group 2
Group 3
Group 4
Group 5 results with controlled cooling.
1C (C denotes controlled cooling)
#1 Jen's Juicy Fruit Variation (Red Matte) C/6
EPK 10%
Gillespie borate 9%
Nepheline syenite 49%
Flint 12%
Whiting 11%
Lithium carbonate 9%
Soda ash 10%
Titanium dioxide 5%
Red iron oxide 10%
2C
#2 - Jen's Juicy Fruit Variation 2 (Red Matte) C/6
EPK 10%
Gillespie borate 9%
Nepheline syenite 49%
Flint 12%
Whiting 11%
Lithium carbonate 9%
Standard Ceramic's #487 Red Stain 10%
Soda ash 10%
Titanium dioxide 5%
#2 normal cooling same formula
3C
3 - Pete's Tomato Red #3 C/6
Kona F-4 (Minspar) 33.7%
Frit 3134 9.8%
Bone ash 10.7%
Whiting 3.8%
Magnesium carb 5.9%
EPK 12.5%
Flint 23.7%
Bentonite 2%
Red iron oxide 8%
4C
4 - Tomato Red #13 C/6
Frit 3134 10.8%
Nepheline syenite 23.1%
Bone ash 10%
Magnesium carb 6.2%
Whiting 7.7%
EPK 21%
Flint 21.2%
Bentonite 2%
Red Iron Oxide 10%
#4 without cooling cycle.
5C with cooling cycle
5 - Tomato Red #13 Pumpkin Orange C/6
Frit 3134 10.8%
Nepheline syenite 23.1%
Bone ash 10%
Magnesium carb 6.2%
Whiting 7.7%
EPK 21%
Flint 21.2%
Bentonite 2%
Red Iron Oxide 10%
Rutile 2%
#5 without cooling cycle.
6C with cooling cycle.
6 - Tomato Red #13 with spodumene C/6
Frit 3134 11%
Spodumene 11.2%
Bone ash 7.9%
Magnesium carb 6.3%
Whiting 7.9%
EPK 21.6%
Flint 21.7%
Neph Syenite 11,8%
Bentonite 2%
Red Iron Oxide 10%
6 - without cooling cycle.
8C - with cooling cycle.
8 - Jen's Juicy Fruit Variation (Red Matte) Cone 6
EPK 10%
Gillespie borate 9%
Nepheline syenite 49%
Flint 12%
Whiting 11%
Lithium carbonate 9%
Soda ash 10%
Titanium dioxide 5%
Black Iron Oxide 6%
8 - without cooling cycle.
12C - with cooling cycle.
12 - Jen's Juicy Fruit Variation Whiting C/6
EPK 9%
Gillespie borate 10%
Nepheline syenite 50%
Flint 7%
Wollastonite 15%
Lithium carbonate 9%
Soda ash 10%
Titanium dioxide 5%
Black iron oxide 6%
12 - without cooling cycle.
18C - with cooling cycle.
18 - Jade Green C 5/6
G200 38.1%
Barium Carbonate 19%
EPK 9.6%
Flint 9.5%
Gillespie Borate 9.5%
Zinc Oxide 9.4%
Copper Carbonate 4.9%
18 - without cooling cycle.
Great experiments. I have tested many of these glazes with a different schedule. Basically a similar heating cycle but the cooling was done dthe following way: fast to 1800 then up to 2000 at 50/hr.
ReplyDeleteI have results posted on http://vvargespottery.typepad.com/vvarges_pottery/2011/01/old-iron-red-photos.html
Also look for results on Coleman teadust with same schedule. Send me an email if you want further details.