Basic machine design same as the 72711 series but with special belt head wheel configuration and belt head guarding. The allocation of the guide wheels and pulleys allows for special belt grinding applications such as grinding on the slack belt. The contact wheels are quickly changeable by means of a quick fit system to allow for the use of a wide range of different diameter contact wheels. The 72713 series is especially useful for belt grinding, linishing and finishing of turbine blades, knifes, implants and other complex shaped work pieces.