Abstract: Molten aluminous oxide abrasive, particularly molten mixtures of alumina and zirconia, are rapidly cooled and solidified by pouring into an agitated molten metal bath, having a boiling point above the temperature of said molten abrasive, such as molten tin, while being protected from oxidation. The solidified abrasive particles float to the top of the metal bath, are removed and separated from adhering metal, as by centrifuging, and crushed to abrasive grit-sized particles.

Abstract: A method and apparatus for conditioning steel by grinding at a constant metal removal rate by monitoring net power and the normal force between the wheel and the workpiece, and adjusting the normal force to achieve a given, predetermined metal removal rate is based on the relation between power and normal force at constant wheel speed. A semi-automatic method, by operator control of the normal force, and a fully automatic method are disclosed. Provision for correcting the force in response to wheel wear is optional.

Abstract: A lens grinding machine with a radially adjustable work holder on which various sizes of lens carriers with lens blanks to be ground, may be mounted and moved at various predetermined radii across the peripheral abrasive surface of a radially adjustable grinding wheel rotatable in a plane normal to a plane of movement of the lens blanks. The grinding wheel has a slotted support center with flexible and resilient deformable walls supporting bonded abrasive segments containing alkali insoluble metal coated abrasive in an alkali soluble metal bond and is mounted on an arbor adapted with means to clamp the wheel and to vary the shape of the deformable walls and radius of the wheel.