A rotary cutting tool includes a main body, a shank portion having a rearward end, and a flute portion having a forward end with one or more flanks. One or more connecting fluid holes are in fluid communication with a central fluid hole and terminates at a flank at the forward end of the cutting tool. One or more twisted fluid holes extend through a lobe in the flute portion and terminates at a flank at the forward end of the cutting tool. A cross-sectional shape of the connecting fluid holes and the twisted fluid holes is selected to provide enhanced delivery of fluid to the cutting edge. In one aspect, the rotary cutting tool is a modular drill and the flute portion has a pocket for holding a replaceable cutting insert.

A drill bit for drilling into masonry or rock includes a drilling head at its forward end, a clamping shank at its rearward end, and a helical conveying portion extending between the drilling head and the shank. The helical conveying portion includes at least two helically extending flutes separated by at least two helically extending webs. The helical conveying portion has a changeover portion, a pre-changeover portion between the drilling head and the changeover portion, and a post-changeover portion between the changeover portion and the shank. In the pre-changeover portion, the flutes have a pre-changeover pitch, the first web has a first pre-changeover web width α, and the second web has a second pre-changeover web width α′. In the post-changeover portion, the flutes have a post-changeover pitch, the first web has a first post-changeover web width β, and the second web has a second post-changeover web width β′. The post-changeover pitch is greater than the pre-changeover pitch, the first post-changeover web width β is less than the first pre-changeover web width α, and the second post-changeover web width β′ is greater than the second pre-changeover web width α′.

A rotary cutting tool is provided having a body and a fluid passage. The body has a shank portion and a cutting portion. The body extends lengthwise along a central axis between a shank end and a cutting end. The cutting portion includes a fluted section and a plurality of teeth extending axially outwardly from the fluted section at the cutting end. The fluted section includes a plurality of flutes disposed within an exterior surface of the fluted section. The cutting portion includes an internal cavity disposed within the fluted section and open to the cutting end. The internal cavity is defined by an interior wall surface. The cutting portion includes a plurality of channels disposed within the interior wall surface and open to the internal cavity. The fluid passage extends through the shank portion to the internal cavity.

A rotary cutting tool having a lengthwise extending central axis is provided. The tool includes a shank portion and a cutting portion. The cutting portion is connected to the shank portion, and includes a fluted section and a plurality of teeth. The fluted section includes a plurality of flutes disposed within an exterior surface of the fluted section. The cutting portion includes an internal cavity disposed within the fluted section and open to a cutting end. Each tooth includes a front side surface, an exterior side surface, an interior side surface, and an axial end surface. The front side surface intersects with the axial end surface to form an axial end cutting edge that extends radially between an outer radial tip and an inner radial tip, and the outer radial tip is disposed axially outside of the inner radial tip.

A rotary cutting tool cutting insert is provided that includes front, aft, exterior, and interior side surfaces, an axial end surface, and a base surface. The exterior side surface intersects with the front side surface. The interior side surface intersects with the front side surface. The axial end side surface intersects with the front side surface at an axial end cutting edge, with the exterior side surface at a first outer axial edge, and with the interior side surface at a second outer axial edge. The base surface intersects the front, exterior, and interior side surfaces and the aft surface. The base surface intersects the front side surface at an inner edge. An outer radial tip is disposed at a first heightwise distance from an inner edge, and an inner radial tip is disposed at a second heightwise distance from the inner edge.

A method for producing a drill shaft for a wet drill bit includes forming N, where N≥1, strip materials into a tubular body where the tubular body is integrally joined at strip edges of the strip materials by N connection welds. At least one strip material of the strip materials is provided with at least one recess before the integral joining of the strip edges.

A core bit for producing a borehole in a workpiece includes a cutting portion with one or more cutting segments, a drill shaft portion with a tubular drill shaft, and a connecting device which connects the cutting portion and the drill shaft portion releasably or non-releasably together. The tubular drill shaft is configured as a welded spiral tube.

A drill body and a drill are disclosed. The drill body has a rotational axis and includes a peripheral chip flute extending along a periphery of the drill body. A peripheral chip flute cross-section has a centre line extending in a plane extending perpendicularly to the rotational axis, and through the rotational axis. The peripheral chip flute cross-section has a radially inner side extending perpendicularly to the centre line, and first and second lateral sides connecting to the radially inner side. The radially inner side has a length L1 within a range of L1=0.95×D/4 to L1=1.2×D/4. Each of the first and second lateral sides has a length LS1, LS2 within a range of D/4 to 1.3×D/4. The first and second lateral sides diverge from each other in a direction radially outwards from the radially inner side.

A rotary cutting tool includes a main body, a shank portion having a rearward end, and a flute portion having a forward end with one or more flanks. One or more connecting fluid holes are in fluid communication with a central fluid hole and terminates at a flank at the forward end of the cutting tool. One or more twisted fluid holes extend through a lobe in the flute portion and terminates at a flank at the forward end of the cutting tool. A cross-sectional shape of the connecting fluid holes and the twisted fluid holes is selected to provide enhanced delivery of fluid to the cutting edge. In one aspect, the rotary cutting tool is a modular drill and the flute portion has a pocket for holding a replaceable cutting insert.

An auger includes a body having a first end, a second end opposite the first end, a stem that extends from the first end to the second end and defines an axis of rotation, and a flute helically wrapped around the stem. The auger also includes a shank at the first end of the body configured to be received by a power tool and a cutting head at the second end of the body. The cutting head includes a cutting edge, a spur, a feed screw with a thread, and a cutting face positioned adjacent the cutting edge. The cutting head defines a step at an interface with the body, and wherein the cutting head has a maximum diameter that is greater than a maximum diameter of the body.