FIG. 1 is a front, right side and top perspective view of a grinder attachment showing my new design;
FIG. 2 is a rear, left side and top perspective view thereof;
FIG. 3 is a left side elevational view thereof;
FIG. 4 is a front side elevational view thereof;
FIG. 5 is a rear side elevational view thereof;
FIG. 6 is a top plan view thereof; and,
FIG. 7 is a bottom plan view thereof.
The broken lines shown in the drawing are for illustrative purposes only and form no part of the claimed design.