Double-sided high feed milling insert, high feed milling tool and method

A double-sided milling insert (30;30') for high feed milling of metal workpieces with a trigonal basic shape and comprising upper (31) and lower (32) faces facing in opposite directions and convex clearance surfaces (33) extending between the upper (31) and lower (32) faces. Each one of the faces comprises a recessed support surface (34A,34B), the support surfaces (34A,34B) being substantially parallel to each other, and having a cavity (35) therein for receiving a fastening means. Intersections of the convex clearance surfaces (33) with the upper and lower faces (34A,34B) form convex cutting edges (37A,37B;37A',37B') when seen in a plan view (fig. 1A) and a rake face (38) is provided adjacent the convex cutting edges (37A,37B,37a',37b'). Each convex cutting edge (37A,37B,37a',37b') is concave when seen in a side view (Fig. 1B) and comprises a substantially straight cutting edge portion (39A,39B;39A',398') on each side of a curved cutting edge portion (40A,40B;40A',40B') when seen in a plan view (fig 1a). A m