Cutting insert and drilling tool for drilling in solid materials

A drill comprising a drill shaft having an axis and a cutting end;

• and at least one cutting insert mounted on said end, said cutting insert comprising a polygonal body formed with at least three cutting vertices and respective cutting edges extending continuously between each two of said cutting vertices and delimiting a rake face of said body, at least one of said cutting edges having a setback substantially midway therealong forming a constriction of said body and subdividing said one of said cutting edges into two mutually inclined outwardly extending rectilinear partial edges including an angle of up to 170.degree. between them, said partial edges running to respective ones of said cutting vertices from said setback and defining respective protruding cutting points at the respective cutting vertices along said one of said cutting edges, whereby two of said cutting points are provided along said one of said cutting edges, said cutting insert being oriented on said end of said shaft such that advance of said shaft into a solid material to be drilled brings both of said points into engagement with the material.