Abstract: A spacer disc is placed onto the drive shaft of a hand-held grinder to position a cut-off disc or cut-off wheel at or beyond the end of the shaft. An annular insert at the proximal face is placed against the backing plate and a concave distal face is positioned against the cut-off disc. The spacer disc is composed of a spacer body of semi-rigid material with an open axial core. A flanged retainer nut secures the cut-off disc onto the grinder shaft against the distal face of the spacer disc. This arrangement permits the tool to be held with the cut-off disc flush to a flat workpiece surface.

Abstract: A plastic backing plate for cut-off wheels is herein disclosed, comprising a plastic circular plate which is placed directly behind or under an abrasive cut-off wheel. It is held in place by the wheel and the center nut that is typically used to secure only the cut-off wheel. During use, the backing plate helps to stabilize the cut-off wheel and maintain its shape while turning, thereby providing a more precise and accurate cut. Additionally, since a smaller amount of material is being removed, more material is left behind to perform additional welding on or other machining operations. Also, the life of the cut-off wheel is extended as well, since a reduced amount of cutting is taking place.