There is provided a drill tool assembly for drilling metallic or other materials, comprising a holder having a mounting slot in which a cutting insert is positioned, and a through tool coolant supply system. The drilling tool system allows for the application of coolant to the rake surfaces of the cutting insert in a manner which facilitates enabling higher penetration rates while maintaining integrity of the cutting edges of the cutting insert. The drilling tool system comprises a holder having a rotational axis and mounting slot. A cutting insert with sides positioned adjacent the side surfaces of the mounting slot and cutting edges extending from the rotational axis is mounted in the slot. The insert includes rake surfaces adjacent the cutting edges that are positioned above the mounting slot. At least one coolant channel is disposed with at least one coolant outlet directed at the sides of the insert at a position below the rake surfaces. The coolant outlet is configured to disperse coolant in a curtain across the entire rake face of each cutting edge.

The present invention provides a twist drill. A cone portion is provided at a front end of the operating portion, and an exterior surface of the operating portion is provided with a spiral flute for shunting cutting chips. The exterior surface of the cone portion is provided with a plurality of composite cutting blade groups which are sequentially enlarged in diameter from the front end to the rear end of the cone portion. The cone portion is provided with a top blade on the tip. In use, the top blade is used for positioning, and the cutting process is carried out by the top blade and the composite cutting blade groups.

An indexable center drill structure comprises a holder, an insert, and at least two screws. The screws are locked to at least two screw holes of the holder and at least two positioning holes of the insert. Through cooperation of two positioning posts and two positioning notches of the holder and the insert, the insert is fixed and locked to an insert attachment seat of the holder in a longitudinal direction and in a transverse direction. Thus, the locking strength between the insert and the holder is increased, and the overall structure is simplified.

A drilling tool includes a tool body having a center axis defining a longitudinal direction of the drilling tool. The tool body has an axially forward end and an axially rearward end, the distance in the longitudinal direction between the forward end and the rearward end defining a length of the drilling tool. At least two indexable cutting inserts are arranged at the axially forward end, a first indexable cutting insert being arranged at a radially inner position and a second indexable cutting insert being arranged at a radially outer position. The tool body includes a first flute portion extending axially rearward from the first indexable cutting insert and a second flute portion extending axially rearward from the second indexable cutting insert. The first flute portion transitions into the second flute portion at an axially forward transition area of the tool body, thereby forming only one flute of the tool.

A drilling tool includes a tool body having a center axis defining a longitudinal direction of the drilling tool. The tool body has an axially forward end and an axially rearward end, the distance in the longitudinal direction between the forward end and the rearward end defining a length of the drilling tool. At least two indexable cutting inserts are arranged at the axially forward end, a first indexable cutting insert being arranged at a radially inner position and a second indexable cutting insert being arranged at a radially outer position. The tool body includes a first flute portion extending axially rearward from the first indexable cutting insert and a second flute portion extending axially rearward from the second indexable cutting insert. The first flute portion transitions into the second flute portion at an axially forward transition area of the tool body, thereby forming only one flute of the tool.

A step drill bit includes a shank and a body having a proximal end adjacent the shank and a distal end opposite the proximal end. The body defines a plurality of axially stacked, progressively sized steps including a first step at the distal end, a terminal step at the proximal end, and a plurality of intermediate steps having incrementally increasing diameters disposed between the first and terminal steps. The step drill bit also includes a plurality of cutting edges each disposed along one of the plurality of steps. Each edge defines a helix angle and a radial rake angle. The radial rake angle and the helix angle of the cutting edge at the terminal step is greater than the radial rake angle and the helix angle of the cutting edge at the first step.

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 tool bit with a surface layer metallurgically bonded on a substrate layer using electrospark deposition (ESD) that allows the tool bit to reduce camout and engage a fastener head for one-handed starting and removal. The surface layer has a rougher finish, compared to conventional tool bits, and therefore better grips engagement surfaces of a mating recess of the fastener during use. The reduction of camout provides greater durability to the tool bit and resists erosion and wear of the engagement surfaces of the fastener.

A tool bit with a surface layer metallurgically bonded on a substrate layer using electrospark deposition (ESD) that allows the tool bit to reduce camout and engage a fastener head for one-handed starting and removal. The surface layer has a rougher finish, compared to conventional tool bits, and therefore better grips engagement surfaces of a mating recess of the fastener during use. The reduction of camout provides greater durability to the tool bit and resists erosion and wear of the engagement surfaces of the fastener.

A wood drill includes a clamping portion for connecting, for conjoint rotation, to a tool fitting of a portable power tool, and a head portion which is provided with a centering geometry. The clamping portion is formed at a first end, remote from a workpiece, and the head portion is formed at a second end, close to a workpiece, of the wood drill. The clamping portion is connected to the head portion via a shank portion. A maximum outside radius of the head portion is greater than a maximum outside radius of the shank portion. The head portion has at least one main lip with at least two stages for introducing a bore with a predefined inside radius into a workpiece. An outside radius of a main lip base is less than 60%, preferably less than 50%, of an outside radius of the head portion.