I cut high-density foam circles and then glued them to old bats. Bats are a thin slab of wood, plaster, or plastic used to support pottery forms while throwing. Because the bat can be lifted from the wheelhead, there's no need to directly handle your clay project and risk distorting its shape. The foam lifted the trimming surface four inches, allowing me to keep my back straight. The foam also supports the platter floor, keeping it flat while preserving the rim from warping now that it's not bearing the platter's weight. I use rubber balls in varying sizes to support the centers when trimming bowls.