US Patent 7669939 Buffing ball made of compressible material

A surface finishing ball of compressible material, adapted to be driven on a rotational axis is made from a layered body of compressible material that is formed in multiple disk-like layers that are separated in planes generally perpendicular to the rotational axis. Layers are also slit on circumferentially spaced planes that extend generally radially from an outside surface to define a plurality of foam fingers. A clamping system is used to compress and hold a center portion of the layered body in a direction along the axis of rotation such that the uncompressed outer ends of the fingers define a generally spherical ball.