The 20cm vase on the left is thrown from what I thought was a very plastic body, I achieved close to the same thickness top-to-bottom (5mm). The one on the right was the same original height, 20cm. But it has dried down to only 18cm high, it shrinks 14% (vs. 6% for the other). The thinnest part of the wall is near the bottom, only 2mm thick! How is it possible to throw that thin? The body is 50% ball clay and 50% bentonite. Bentonite, by itself, cannot be mixed with water, but dry-blended with fine-particled ball clay it can. It took about 4 days to dewater the slurry on my plaster table. This is the poorest drying body one could possibly use. But there is the lesson here: Even this can be dried crack-free. How? One month under cloth and plastic to assure water content throughout! This means that pretty well any other body can be dried without cracks if done sufficiently evenly.
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