Abstract: A cutting-tool insert having a cutting edge at the periphery of at least one of its side faces, and a plurality of serrations in the cutting edge. The side faces of the insert are formed with a plurality of recesses between its center and the cutting edge. The plurality of recesses are spaced from each other around the center of the side face, and are also spaced from the serrated cutting edge, to define a margin between the cutting edge and the recesses extending continuously along the length of the cutting edge following the serrations. Also described is a cutting tool using such inserts.

Abstract: A master pattern assembly for providing eyeglass lens circumference shape guidance in an edge grinding machine, suitable for creation of a replacement lens for eyeglasses where one lens is broken and one remains intact. The intact lens is removed from the frame, its optical center is located, and the lens is adhered to a dual-adhesive pad which is also adhered on a side opposite the lens to a body block. The block and pad define coaxial throughgoing bores centered on the optical center of the lens. The bore of the block is then received on a rotatable axis of a conventional edge grinding machine, where the assembly is rotated and the circumference of the intact lens acts as a cam in contact with a pattern follower, controlling circumference formation of a new lens.