Modification Date: 2016-12-03 13:48:07
|New Zealand Kaolin||10.0||50BG|
|Ferro Frit 3110||6.0||50BG|
|Mason 6336 Blue Stain||250.0||GM|
Alert: This recipe contains units of measure, it cannot be imported into Desktop Insight as is.
This is a production batch mix of original container bags intended to fill an industrial mixer.
You must recalcuate it to percentages and then to the total you need (if it has not be done here).
This body is not available for sale. Yet. I am beta-testing it. I have done a long series of test mixes in search of a blend of North American materials that will produce a fritted white low-fire porcelain. But I was not able to do so. The difficulty is that the glassy phase of the frit amplifies the color of any iron available in the body (even tiny amounts) to produce a bone or ivory white.
The only solution was a switch to New Zealand Kaolin (which contains only 0.15% iron) and VeeGum. The result is dramatically better. However a pinkish color still remained. This made it necessary to add a small amount of blue stain. Now it has the color of cone 10 reduction porcelain!
This body pairs with G2931K clear glaze (the fully fritted version of G2931F) and a drop-and-soak firing schedule. Look for a links to that here or google it.
The secrets of this body are thus:
-The 30% frit: Frit is expensive (no normal porcelains contain it because of this). But it makes the impossible possible!
-The NZ Kaolin: The whitest available in the world.
-The VeeGum: The most plastic super-white clay in the world.
-The silica for glaze fit and as a structural framework.
As noted, this body will be among the most plastic you have even used (of any kind). But this is only true if it is stiff enough. If you try to use it soft the shrinkage will be much higher and you risk drying cracks.
One caveat: This is not an attempt to rival the fired surface of cone 6 Polar Ice, it is not as smooth and dense (but it is almost zero porosity). You could, of course, fire higher to produce higher density. But remember, this is frit-ware, warping issues will creep in quickly as temperature is increased. Firing higher than cone 03 will not necessarily produce more strength either. It will produce more fired shrinkage (which is already quite high).
If we were to manufacture this is could cost $100 a box. But before dismissing this think about the advantages of using it for making smaller pieces:
-Fast firing: two or three times a day (as little as 3 hours start to kiln opening).
-The appearance of cone 10R but with far brighter colors.
-High strength (rivaling any other temperature).
-Throw ware ultra thin and light.
-A perfectly fitted ultra-clear glaze that is far cheaper to make than commercial glazes (and works better).
-Dramatic reduction in wear-and-tear on kiln elements and energy usage.
-Remember to factor in the fact that you will be able to charge more for pieces when you calculate clay-cost-per-piece.
This is an all-fritted version of G2931F Zero3 transparent glaze. I formulated this glaze by calculating what mix of frits must be employed to supply the same chemistry of the G2931F recipe. The mug is made from the Zero3 porcelain body (fired at cone 03) with this glaze. This glaze fits both the porcelain and the Zero3 terra cotta stoneware. The clarity, gloss, fit and durability of this glaze are outstanding.
The mug on the left is Plainsman P600 (a #6 Tile kaolin based porcelain). The other is Zero3 Porcelain, fired at cone 03 (New Zealand kaolin plus frit). Alone the P600 mug looks good, but beside the Zero3 it looks drab. It is grey and not clearing the bubble clouds over the underglaze. The Zero3 withstands thermal shock better and it is as strong or stronger. It seems incredible that this could be when it is fired 13 cones lower! Grolleg kaolin based reduction porcelains compare better with the Zero3 body.
This is Zero3 porcelain made using Dragonite Halloysite (instead of New Zealand Halloysite). It is the L2934C recipe. It was fired to cone 03 and glazed with G2931K clear glaze (which has fired crystal clear and flawless). I fired at 1200F/hr to 1950F, held it for 15 minutes, cooled at 999F/hr to 1850F and held it for 30 minutes, then dropped as fast as the kiln would do. It has some translucency and fires with a purplish hue (the NZ burns blue-white and is more translucent).
These fritted porcelain bars are fired at cone 06, 04, 03 and 02 oxidation (bottom to top). The body contains 0.2% blue stain. Notice that almost no color develops at the lowest temperature. Glass development is needed.
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By Tony Hansen