The objective of this research was to experimentally study the forces imparted on the workpiece during a typical shoe centerless grinding cycle on a flat (unprofiled) outer diameter. The data obtained provide insight into the forces developed between the machine structure and workpiece during both idling and steady-state grinding. These workpiece-machine structure interactions involve the grinding wheel, support shoes, and magnetic driver plate. The influence of the work-piece rotational center offset on the resultant shoe forces was examined by varying the workpiece rotational center relative to the fixed rotational center of the magnetic driver plate. The magnitude and direction of the resultant force and its effect on the final workpiece surface finish quality were examined.