member 2 for any particular size and shape of convex recess 7 is the same regardless of the method of connecting the grinding cup to the output drive shaft of a grinding machine standardizing the components will reduce manufacturing costs and the amount of inventory required the drive connection member 3 in the embodiment illustrated in fig1 is illustrated as a separate component to be connected to the output drive shaft of a grinding machine utilizing one of the known drive methods identified previously the drive connection member in fig1 has a first section 22 adapted for connection to the grinding member 2 and a second section 23 adapted to detachably connect to the output drive shaft of a grinding machine the first section 22 in the embodiment illustrated the outer wall 24 of first section 22 generally cylindrical in the embodiment shown although other shapes are possible defines a recess 25 adapted to receive the stub 18 of the grinding member 2 the stub 18 is adapted to fit within recess 25 so that the grinding member 2 cannot rotate or spin relative to the drive connection member 3 the bottom 26 of the outer wall 24 is sized and shaped to fit against the top edge 19 of the cylindrical section 16 of means 13 on the grinding member 2 while the stub 18 and recess 25 are illustrated as circular in cross section other shapes are possible such as elliptical oval square rectangular hexagonal etc as noted previously it is within the scope of the present invention to have a stub on the drive connection member fit within a recess on the grinding member the second section 23 of the drive connection member is integral with the top 27 of the outer wall 24 of the first.