Carol Durnford on thu 4 apr 96
Hello, I've been watching the threads here and they have been
great. I'm learning a lot. I went to the Minneapolis NCECA and the Clayart
presentation by Joe Molinaro, but Rochester was just too far for my budget.
Previously, I mentioned that I was using pulp fiber from the paper
mill outside of town. I have been determining the percentage by weight of
wet pulp fiber to weight of dry clay based on the fact that the pulp
analysis shows it is 80% water and sometimes more. Since I want more
actual fiber weight which holds water, I use that 80% water or part therof
as weight towards in the weight of water in the final mix.
The important thing has been to keep the fiber moist as it is the
weight of the water in the fiber, plus the fiber itself that evaporates or
burns out making the pot more porous and light weight pot (I don't even
know if all of that was right or made sense). But, the more useful part
has been the strengthening of the greenware by the fiber; especially large
pieces. It is like using nylon fibers in clay for hand building.
Regardless, my biggest problem is getting enough grog or sand-like material
into the paperclay to eliminate that "sticky" workability problem. Perhaps
I need to go the perlite way after all and live with that texture.
I'm also including two recipes for ^6 that have been good for me.
About five years ago I went through all of the Ceramics monthly magazines
back to the 1960's that are in the library at U of M, and zeroxed the things
I thought were interesting ( glazes, techniques etc.).
Clear ^ 4 to ^10. Reduction, but I've had great results in oxidation.
Gerstley Borate 21%
Wollastonite 8%
Nepheline Syenite 30%
Kaolin 10%
Flint 31%
I've been using this on underglaze decorated porcelain though
recommendations stated that it fits most stoneware bodies. It gives a nice
smooth clear finish. There has been some minor crazing on ^10 porcelain
fired to ^6, but little to no problems on ^6 porcelain fire to ^6, for
obvious reasons of clay maturity. I'm also curious whether it scratches
easily.
The second is a Celadon ^6 reduction
Potash Feldspar 41.5%
Whiting 15.0%
Zinc Oxide 12.0%
China Clay 4.5%
Flint 27.0%
Red Iron Ox. 1.0%
A satin finished celadon that where thick, ran a little, and turned a light
blue. I had slightly overfired it with #7 cone at about 2:30 and it glossed.
Could probably be made into a gloss for ^6.
Enjoy it all. Thanks.
Dave D. Finally a sunny day. ""YEA!!!" I don't know about y'all but I'm
going outside and get my once a year tan.
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