Abstract: A device for boring holes has a geometrical longitudinal axis, a clamping zone, a shank having a front end zone, two turnover plates fastened on the front end zone of the shank in opposite positions, and a chip space in front of each turnover plate. In the shank, a longitudinal slot runs radially to the geometrical longitudinal axis, which is open towards the front end zone and has a bottom that extends so far towards the clamping zone that the shank halves thus formed can be bent forward at the front end zone to a degree that is sufficient for fine setting the bore diameter. Beyond the bottom of the longitudinal slot, a tapped hole in the shank is coaxial with the longitudinal axis. A coaxial rest hole in the shank in the inner zone of the longitudinal slot is intersected by the longiudinal slot.

Abstract: The reamer has a flat rectangular reversible cutting bit which has a wide-side face, a wide-side contact surface parallel to said wide-side face and a narrow-side contact surface and possesses a cutting edge extending parallel to the longitudinal axis of a revolvable body and projecting above the circumferential surface of the body. The reversible cutting bit is mounted detachably in a recess of the revolvable body and makes contact with a supporting surface extending substantially in a radial direction and also with a base support extending at right angles to the former. The radial support surface of the revolvable body is narrower than the base support of the recess. The wide-side contact surface of the reversible cutting bit makes contact with the base support over a large area. The narrow-side contact surface of the reversible cutting bit is disposed at the radial support surface of the revolvable body.

Abstract: A reamer has a head with a recessed bearing plane which absorbs the pressure of a clamping member which presses against one side of a cutter knife. A counter member is positioned with one side displacable on the recessed bearing plane in the direction of increased cutting diameter. The cutter knife is held between the clamping member and the counter member. The counter member has a region with a straight holding portion which supports the cutter knife. The clamping member and counter member have congruent oblong holes which extend in the direction of increased cutting diameter. These holes are traversed by a clamping screw which is screwed into a threaded hole in the head. When the screw is tightened, the three piece unit of clamping member, cutter knife and counter member are tightened in the reamer head.

Abstract: A chucking reamer has a flattened section on its head, with a crescent-shaped recess. A crescent-shaped body which retains a cutter device is held in the cresent-shaped recess by a fixing screw and a pair of headless screws are threaded into the head to adjust the position of the crescent-shaped body and the cutting device. The carbide cutter device and the steel crescent-shaped body are in one piece. The fixing screw has a conical head which fits into a conical recess in the crescent-shaped body. An inner threaded hole is provided through the head, running perpendicularly from the bottom face of the crescent-shaped recess, for receiving the shank of the fixing screw.

Abstract: An on-edge, double positive rake, indexable cutting insert in which a short cutting edge is formed along one side of one face surface of the insert while a longer cutting edge is formed along an angularly related side of the other face surface of the insert. Inserts of this type are particularly well suited for use as the outer inserts in an end mill having helical slots for receiving the inserts. When so used, two inserts are placed in side-by-side relation in one slot with their short cutting edges located in active cutting position while one insert is positioned in an adjacent slot with its long cutting edge located in active cutting position and axially overlapping the gap between the two short cutting edges. With this arrangement, material which is left uncut between adjacent inserts in one slot is cut away by the overlapping insert in the adjacent slot. Each insert includes edge surfaces defining clearance faces for the two cutting edges and enabling each cutting edge to make a right angle cut.