a tool for cutting or milling casing in a well is disclosed . it includes a plurality of blades extending outwardly to a substantially radial position for cutting the walls of casing strings and removing a predetermined length of the casing strings in a cutting action . the blades have cutting elements positioned on leading faces of the blades to engage the casing strings in a cutting action without tripping or removal from the bore hole . the cutting elements can be arranged in rows and columns . the cutting elements can be shaped to continually present a sharp cutting edge to the object being milled . the cutting elements can be inclined at a negative axial rake angle to cause the metal chips cut from the object being milled to break off at short lengths . the cutting element can also have surface irregularities to cause the metal chips cut from the casings to break off at short lengths . the cutting element can also have stress relieving grooves to prevent the propagation of a crack across the face of the element .