Abstract: A seal assembly for a wafer grinding machine is mounted on a housing in which a grinding wheel is contained. The seal assembly is formed of a pair of flexible strips which are secured over an opening in a plate mounted on a housing enclosing the grinding wheel for sealingly engaging a respective planar surface of a wafer which is introduced through the opening by a rotatable chuck. The edges of the sealing strips define a V-shaped gap to ensure that the edges are disposed in biased relation against each other and against a wafer which passes between the strips. A tube provided with perforations is disposed to blow air to clear debris from the wafer.