Abstract: A tapered bearing for the drive drum assembly of a belt grinding machine that employs multiple, parallel, abrasive grinding belts, and back-up shoes for pressing the belts against the surfaces on a workpiece to be ground. The drive drum assembly, in cooperation with small pulleys operatively associated with the contouring head, keeps the abrasive belts properly trained. The central shaft of the drive drum assembly, which has a plurality of large pulleys and spacers positioned therealong, is secured between a fixed bearing support and a laterally movable support bracket. A tapered bearing is fastened to one end of the central shaft, and a complementary shaped aperture is defined in a spindle retained in the movable support bracket. When the movable support bracket is shifted inwardly, by the hydraulic circuitry of the grinding machine, the tapered bearing fits snugly into the aperture so that the drive drum assembly is supported in a rigid, sag-free manner.

Abstract: A method of forming a hydrostatic nut that cooperates with a lead screw for translating a wheel head, or carriage, on a grinding machine, such as a cam grinder. A lead screw standard, or master, which is externally threaded, is inserted into a cylindrical mold, which is internally threaded. The standard is retained therein by pressure plates that seal off opposite ends of the open bore of the mold. Beads of wax, or tape, or some other rigid instrumentality, are adhered to the exterior surfaces of the helical threads on the standard, while the rest of the standard is treated with a release coating.A continuous cavity is defined between the internal threads on the nut and the external threads on the standard. An epoxy resin or other castable polymer is introduced through an inlet port in the mold into the cavity. The castable polymer is allowed to cure into a rigid mass that adheres to the internal threads on the mold except for the helical beads.