A modular drill apparatus (100) includes: a shank (110) having a pocket (112); a cylindrical post (117) centrally secured within a bottom (114) of the pocket (112); a cutting tip (130) including a lower portion (131) including a central bore (136) which receives the cylindrical post (117), an upper portion (132) and a channel (134) therebetween; and an insert assembly (150) interfitted within and supported by the channel (134), the insert assembly (150) being expandable along a length thereof for securing the cutting tip (130) to the shank (110) within the pocket (112) by providing an interference fit and retractable along the length thereof for releasing the cutting tip (130) from the pocket (112) by overcoming the interference fit.

A tool tip is integral with or removably secured to a tool body and configured to machine a metal object. The tool tip has a tool tip diameter, a rotational axis and at least one coolant duct. The tool tip includes at least one major cutting edge formed at an intersection of a rake face and a first major flank. The rake face forms part of a chip flute. The coolant duct is configured to be in flow communication with discharge orifices located exclusively in the tool tip. The tool tip has an arrangement, such as a row of two or more discharge orifices located exclusively in the rake face of a major cutting edge. The arrangement extends at a non-zero angle relative to the rotational axis.

A rotary cutting tool includes a tool body including a chip flute portion having a plurality of helical chip flutes separated by lobes. In one aspect, a tunable vibration absorber assembly is disposed within a cavity formed in the chip flute portion. In another aspect, the tunable vibration absorber assembly is disposed within a cavity of a replaceable cutting head. In each aspect, the tunable vibration absorber assembly includes at least two tunable absorber masses, a resilient material between the one or more absorber masses and the cavity, and one or more connecting members for preventing relative angular displacement of the one or more tunable absorber masses. The at least two tunable absorber masses are suspended only by the resilient material, thereby enabling the tunable vibration absorber assembly to be tuned to a desired frequency for suppressing torsional vibration of the rotary cutting tool during a cutting operation.

A drill bit for a drill includes a body clearance extending helically along the drill bit, a margin also extending helically along the drill bit, adjacent to and projecting radially beyond the body clearance, and a flank at which the body clearance and the margin terminate at a tip of the drill bit. The margin has a variable width along its helical extension.

A cutting head rotatable about a central axis, includes a tip portion and an intermediate portion. The tip portion has an axially forwardmost tip point contained in the central axis and at least two axially forward-facing front surfaces, each front surface having a radially extending cutting edge. The intermediate portion has at least two head lands circumferentially alternating with at least two chip evacuation passages, each head land having a leading edge extending axially rearwardly from the tip portion. The cutting edges are contained in an imaginary annular ring surface, and a first imaginary radial plane containing the central axis intersects the imaginary annular ring surface to form two imaginary radial cutting profiles. Each imaginary radial cutting profile has consecutively radially outward extending first, second, and third cutting profile portions, and the second cutting profile portion includes first and second concave sub-portions spaced apart by a first convex sub-portion.

A modular drill includes a shank, a retaining pin, a cutting insert, and a locking pin. The shank includes a shank bore having an axial direction leading into the shank bore, and a locking pin opening. The retaining pin includes a retaining pin shaft axially movable positioned with the shank bore, the retaining pin shaft having a locking pin engagement surface. The retaining pin includes a retaining pin head having a retaining pin head engagement surface. The cutting insert includes a cutting insert passage for passing the retaining pin head therethrough; and a cutting insert cavity having a cutting insert engagement surface for engaging the retaining pin head engagement surface. The locking pin is for positioning within the locking pin opening and engaging with the locking pin engagement surface to force the retaining pin shaft to move further in the axial direction.

A cutting head rotatable about a head axis has a cap portion and a rigid mounting protuberance joined to the cap portion. The cap portion has exactly four cutting portions circumferentially alternating with four head flutes and a head base surface facing in an axially rearward direction. The mounting protuberance extends axially rearwardly from the head base surface and has exactly two circumferentially spaced apart convex clamping surfaces. In a cross-section taken in a first horizontal plane perpendicular to the head axis and intersecting the mounting protuberance, only the two clamping surfaces are circumscribed by an imaginary first circle having a first diameter and a center coincident with the head axis. A rotary cutting tool has an elongated tool shank with a head receiving pocket at a forward end thereof and the cutting head of the type described above releasably secured to the head receiving pocket.

A twist drill and an exchangeable head for a twist drill, the twist drill extending along a central axis of rotation and having a front end formed as a drill point with two cutting edges and at least two clearance surfaces. Two helical chip flutes conduct chips away from the cutting edges. Each cutting edge extends in a transition between the clearance surfaces. One of the chip flutes extends from an inner position adjacent to the central axis to a peripheral envelope surface and has a main portion closest to the peripheral envelope surface. Each chip flute is delimited by a side surface including a main rake face, which extends rearward from the main portion of the cutting edge. The cutting edges are contained in an imaginary conical surface, such that the twist drill is operable to generate a bottom profile having the shape of an inverted cone.

A rotary cutting tool includes a tool body including a chip flute portion having a plurality of helical chip flutes separated by lobes. In one aspect, a tunable vibration absorber assembly is disposed within a cavity formed in the chip flute portion. In another aspect, the tunable vibration absorber assembly is disposed within a cavity of a replaceable cutting head. In each aspect, the tunable vibration absorber assembly includes at least two one or more tunable absorber masses, a resilient material between the one or more absorber masses and the cavity, and one or more connecting members for preventing relative angular displacement of the one or more tunable absorber masses. The at least two one or more tunable absorber masses are suspended only by the resilient material, thereby enabling the tunable vibration absorber assembly to be tuned to a desired frequency for suppressing torsional vibration of the rotary cutting tool during a cutting operation.

An insert holder includes a cutting portion and a shank portion. The insert holder further includes a cavity which includes a cavity chamber and a plurality of cavity through recesses which serve to reduce the weight of the insert holder. The plurality of cavity through recesses open out to the cavity chamber and to the periphery of the shank portion. A cutting tool is provided having a cutting insert releasably attached to the insert holder.