a system for rapid replacement of abrasive in machinery which uses the abrasive to finish the surfaces of workpieces that pass through the machinery on a belt , such as so - called widebelt sanders . one preferred embodiment of the system employs an abrasive material that is frictionally held on each edge to mounts . the position of the mounts may be varied to increase or decrease the tension of abrasive material against the working surface of the platen , that the assembly may be removed from the apparatus . in another embodiment , the abrasive material is formed with integral , permanent mounts on the edges of the abrasive material , so that the entire combination may be supplied or replaced as a unit . a variety of configurations of mounts may be used .