Cutting insert and cutting insert holder therefor

A disc milling cutter comprising a cylindrical disc having a plurality of seats formed therein, the seats spaced apart circumferentially with respect to a center axis of the disc, and cutting bits mounted in respective ones of the seats in direct engagement with seat-forming surfaces of the disc, the cutting bits comprising a generally cuboidal body having substantially parallel upper and lower faces, and four side faces, wherein at least one of the upper and lower faces includes four corner regions including two diagonally opposed corner regions that are raised with respect to the remainder of the at least one of the upper and lower faces, the remainder including a center region and two other diagonally opposed corner regions of the at least one of the upper and lower faces, each of the raised corner regions including a relief surface extending to a respective side face to form a raised cutting edge at a transition thereof with the respective side face.

A disc milling cutter comprising a cylindrical disc having a plurality of seats formed therein, the seats spaced apart circumferentially with respect to a center axis of the disc, and cutting bits mounted in respective ones of the seats, the cutting bits comprising a generally cuboidal body having substantially parallel upper and lower faces, four side faces, and cutting edges formed at transitions between at least one of the upper and lower faces and the side faces, wherein the at least one of the upper and lower faces includes raised corner regions at two diagonally opposed corners thereof, respectively, the raised corner regions including relief surfaces extending to respective side faces to form cutting edges at transitions therewith, the side faces defining rake faces, wherein each seat comprises a mounting pocket, each mounting pocket including at least first, second and third walls arranged perpendicular to one another, the first wall oriented parallel to a plane containing both the axis and a radius of the disc intersecting the respective mounting pocket;

• the second wall oriented substantially perpendicularly to the axis, the third wall oriented substantially perpendicular to the radius, the third face including an opening for receiving a respective raised corner region of the cutting bit.