Patent attributes
A rotary tool accessory in one embodiment includes a base, a circular wall extending upwardly from the base about a central axis, the circular wall including an inner face, an outer face and a circular rim, a first cutting group including a first inwardly extending tooth extending from a location directly above the circular wall to a location closer to the central axis than the inner face, a first outwardly extending tooth extending from a location directly above the circular wall to a location farther from the central axis than the outer face, and a first gullet extending downwardly from the rim toward the base, a second cutting group including a second inwardly extending tooth, a second outwardly extending tooth, and a second gullet, and a toothless expanse of the rim extending between the first cutting group and the second cutting group.