Bowls turned from green wood will distort and change shape as the wood dries. If you want to limit the amount of distortion, then it’s best to rough turn the bowl shape, leaving about 1-in. of wall thickness. Then set the bowl aside to dry for a few months before putting it back on the lathe to turn the final shape. In this video, Ernie Conover covers the basics of re-turning a green rough-turned bowl after it has dried for a period of time.