|Monthly Tech-Tip |
These are made from a whiteware having 0.5% paper fiber added. The paper addition speeds up the dewatering time. The clay throws well and the handles pulled extremely well. The mugs were stable enough to attach the handles immediately. Then I just left them out to dry overnight. There were no cracks in the morning, so I turned them upside down and rewet the bottoms by setting a wet sponge on them for a few minutes. That enabled me to trim them.
This measuring cup contains 30 squares of toilet paper or 11 grams (which has disintegrated quickly and has been propeller-mixed). I am about to dump the paper fiber and 1000 grams of plastic porcelain powder into the water and then mix that up and pour the slurry onto a plaster bat. Although the fiber is only 1% by weight of the dry mix, this completely changes the working properties of the clay. It is still plastic, but much more difficult to cut with a knife or wire. It rolls out nicely into very thin slabs and they are very tough and easy to manipulate and build with. As it hardens it is still pretty plastic.When forced to bend it slowly breaks as the fibers release across the boundaries. Two dry pieces of this clay can be joined using only water and they stick together! Of course this paper needs to burn out during firing, so you need good ventilation on your kiln. You might think that this paper clay shrinks much less than the non-paper version. Actually, it shrinks more (likely because of the increased percentage of water needed). The paper is imparting strength, that strength is enough to resist cracking on drying.