Abstract: A grinding wheel hub is provided for mounting an abrasive grinding wheel on a grinding apparatus. The hub is adapted for use with an abrasive grinding wheel of the type that has a mounting aperture disposed centrally therein, and a grinding face and a backing face disposed on opposite sides of the abrasive grinding wheel. The grinding wheel hub includes an aperture bushing of substantially cylindrical configuration, adapted for extension through and engagement with the surface of the mounting aperture. A grinding face fastener is disposed on the aperture bushing and is adapted to extend radially outward from the mounting aperture to engage the grinding face of the wheel. A backing flange of substantially discoid shape, extends radially outward from the aperture bushing member and is adapted for being superposed with the backing face. The backing flange has a bond surface adapted to face the backing face. The bond surface includes one or more recesses formed therein.

Abstract: Relatively thin type 27 depressed center abrasive wheels are made from initially flat “green” wheels made in a hydraulic press that has flat upper and lower surfaces in each press cavity. These thin flat wheels are clamped in a fixture that forms the center portions as the wheels are clamped to provide “green” wheels that are not only thin, but that have depressed center portions of undistorted internal geometry. The “green” wheels are then cured in this clamped condition in a furnace at appropriate temperatures that achieve the necessary hardening of the resinous mixture to yield thin depressed center abrasive cutting wheels.

Abstract: An abrasive wheel assembly for use on a grinding or cut-off machine is described. A hub includes a mounting for releasably mounting the hub on the machine and securing structure for securing the hub to the center of the abrasive wheel so as to prevent axial movement of the hub relative to the abrasive wheel. A transverse key and mating keyway comprise a mechanical interlock to prevent rotation between the hub and the abrasive wheel. The keyway may be formed by imbedding a bushing in the abrasive wheel and may be used with epoxy to further secure the hub to the abrasive wheel rotationally.