Abstract: A hold down clamp for a workpiece comprising a plate-like base having planar top and bottom surfaces, and forward, rearward and side edges. An abutment means extends transversely of the upper surface near the rearward edge thereof. A vertical clamping screw support of inverted L-shape is mounted centrally of the base side edges between the abutment means the base rearwad edge. The free end of the support contains a vertical internally threaded bore. A vertical clamping screw is engaged in the bore and supports a clamping head with a clamping surface adaped to cooperate with the base top surface. The clamp may be removably affixed to a work surface or shifted in free floating manner there along. The clamp base bottom surface has an axial slot, extending from the base forward edge through the base rearward edge, for use when the clamp is to be shifted in guided fashion along a power tool table having a guide slot. A T-guide is provided comprising upper and lower bars joined together.

Abstract: A workpiece supporting fixture pivotally mounted on the table of an abrasion tool enabling the manual shifting of the peripheral edge of the workpiece toward the powered abrasive element of the abrasion tool and the manual rotation of the workpiece with respect to the abrasive element to produce a true and repeatable circular peripheral edge on the workpiece. The fixture comprises a planar plate pivotally affixed to the tool stable and pivotable toward and away from the driven abrasive element. A pivot pin mountable on the fixture at a plurality of predetermined positions thereon, and receivable in a perforation in the workpiece, rotatably mounts the workpiece to the fixture. An arm is rigidly affixed to the fixture plate and extends beyond the edge of the tool table. A stop member is slidably and adjustably mounted on the arm and is fixable with respect thereto.