|Monthly Tech-Tip |
This thrown vessel has sat on this plaster bat for almost 24 hours and yet still has not released. The bat was dry. It had to be slowly pried off with a flat scraper (which deformed it somewhat). When clay bodies are high in ball clay and bentonite they dry slower. If this is taken to an extreme, it can slow down production.
Plaster bats are a key tool used by many potters. But their true value is not understood by most: They produce ware with much less cracking problems
Plasticity (in ceramics) is a property exhibited by soft clay. Force exerted effects a change in shape and the clay exhibits no tendency to return to the old shape. Elasticity is the opposite.