Cutting insert with an array of surfaces receiving clamping forces

A cutting tool comprising a holder, a cutting insert, a clamp for clamping the insert to the holder, and a screw for attaching the clamp to the holder, wherein:

• the holder includes a seat having a bottom seat surface and a supporting surface structure upstanding form the bottom seat surface;
• the insert includes a body forming top and bottom surfaces and a center hole intersecting at least the top surface, a portion of the top surface which extends around the center hole including an array of projections radiating laterally outwardly around the center hole, wherein a distal end of each projection disposed farthest from the center hole defines a tip of the projection, the projections forming at least six tips spaced circumferentially apart, each tip having a planar top face;
• the clamp including an arm having front and rear portions, the rear portion being mounted to the holder by the screw, the arm further including:
• a downwardly projecting nose at the front portion thereof, the nose extending into the center hole, and
• a bottom surface having a pair of spaced contact surfaces located generally behind the nose and arranged to make planar contact with the planar faces of the tips of respective ones of the projections;
• wherein the nose is arranged to press the insert rearwardly against the supporting surface structure, and the contact surfaces are arranged to press the insert downwardly against the bottom seat surface, in response to tightening of the screw.