Abstract: A tool element subassembly, such as an abrasive disc subassembly, for mounting to the spindle of a grinder. The subassembly includes an abrasive disc, a collar nut and, optionally, a backing flange. The central bore in the abrasive disc as well as the hub portion of the collar nut which fits into the bore are both hexagonally shaped to provide a positive drive connection therebetween. The collar nut is either press fit onto the disc or, alternatively, placed directly into the mold for the disc so that the formed abrasive disc is molded directly to the hub portion of the collar nut. In certain embodiments the collar nut includes an integrally formed, enlarged head portion that is adapted to engage the bottom surface of the abrasive disc and is configured to receive a wrench for tightening the subassembly onto, or loosening the subassembly for removal from, the spindle.

Abstract: A tool element subassembly, such as an abrasive disc subassembly, for mounting to the spindle of a grinder. The subassembly includes an abrasive disc, a collar nut and, optionally, a backing flange. The central bore in the abrasive disc as well as the hub portion of the collar nut which fits into the bore are both hexagonally shaped to provide a positive drive connection therebetween. The collar nut is either press fit onto the disc or, alternatively, placed directly into the mold for the disc so that the formed abrasive disc is molded directly to the hub portion of the collar nut. In certain embodiments the collar nut includes an integrally formed, enlarged head portion that is adapted to engage the bottom surface of the abrasive disc and is configured to receive a wrench for tightening the subassembly onto, or loosening the subassembly for removal from, the spindle.