US Patent 9902035 Compact grinding wheel

A grinding wheel for use in a skate blade sharpening system includes a metal grinding ring having an abrasive-coated outer surface for contacting a skate blade to be sharpened during sharpening, and a generally disk-shaped hub to which the grinding ring is fixedly mounted. The hub and grinding ring are configured for mating with an arbor on a rotating shaft of the skate blade sharpening system. Generally the hub is of a less expensive and lower-density material than the grinding ring. In one embodiment, the hub is of a lightweight material such as thermoplastic.