Abstract: The clamp for a milling machine or the like comprises a substantially semi-cylindrical body having inner and outer surfaces with the same center in cross-section. The body has two circumferential ends terminating in two lips. It also has a circumferential slot extending a substantial distance circumferentially from a center of the body toward one lip. A washer has an inner surface matching in contour the outer cylindrical surface in the vicinity of the slot. In use the one lip is placed on the bed of the machine. The other lip is applied over the workpiece. A bolt is then passed from under the bed through the slot and washer, and fastened with a nut to clamp the body against the workpiece and the bed of the machine. Then, if properly placed, the milling tool may operate upon the workpiece.