A cutting insert includes a head portion having a number of cutting edges and a centering pin which is disposed about a central longitudinal axis and which is coupled to, and extends axially away from, the main head portion. The centering pin includes a recess structured to accommodate a portion of a setscrew. The recess includes: a first angled surface disposed generally facing away from a leading end of the centering pin at an acute first angle with respect to the longitudinal axis of the centering pin; and a second angled surface which is positioned opposing the first angled surface at an acute second angle with respect to the longitudinal axis of the centering pin.

In an embodiment, an insert includes an upper surface including a corner part, a lower surface, a side surface, and a cutting edge. The side surface is between the upper surface and the lower surface. The cutting edge is at least at a part of a first region in which the upper surface intersects with the side surface. The cutting edge includes a first cutting edge at the corner part, a second cutting edge, a third cutting edge, and a fourth cutting edge. The second cutting edge is next to the first cutting edge, and also next to the third cutting edge. The third and fourth cutting edges: each have a convex curvilinear shape with first and second radii of curvature, respectively; and extend downward and upward, respectively, in a side view as going farther from the second cutting edge. The second radius smaller than the first radius.

An auger bit for cutting holes. The auger bit includes a body made of a first material. The body has a first end, a second end configured to be coupled to a power tool, a flute, and a longitudinal axis extending centrally through the body. The auger bit also includes a cutting tip made of a second material different from the first material. The cutting tip is coupled to the first end of the body. The cutting tip includes a first shoulder having a first spur, a first main cutting edge, and a first side cutting edge. The cutting tip also includes a second shoulder opposite the first shoulder and having a second spur, a second main cutting edge, and a second side cutting edge. The cutting tip further includes a center spur positioned between the first shoulder and the second shoulder and on the longitudinal axis.

A drill structure comprises a shank part and a bit part. A web is formed on the front end of the bit part. Two sides of the web are tilted backward to form two cutting faces. At least one chip-discharge groove is formed on the surface of the bit part. Each cutting face includes a primary cutting face and a secondary cutting face. The thickness of the prismatic web edge of at least one primary cutting face is smaller than the outer-side width of the primary cutting face. An auxiliary cutting face is extended to the wall of the flute from the cutting edge of the primary cutting face and a portion of a blade back of the secondary cutting face of another cutting face. The present invention decreases the drilling resistance during drilling a hole and increases the service life of the drill bit.

A machining tool, in particular a drill carrier tool, includes a monolithic base body extending in the axial direction which, at least in one section, has a porous or grid-like core structure that is encased in a solid outer jacket. These measures allow less material to be used, while maintaining good mechanical properties. The porous or grid-like core structure is simultaneously used for transporting coolant. The base body is manufactured in particular by means of a 3D printing method.

A drill body and a drill are disclosed. The drill body has a rotational axis and comprises a central chip flute extending along a periphery of the drill body. A central chip flute cross-section has a centre line extending in a plane extending perpendicularly to the rotational axis, and through the rotational axis. The central chip flute cross-section has a depth, as seen along the centre line, and a width as seen perpendicularly to the centre line. The central chip flute cross-section has a maximum depth Dp within a range of Dp=0.75D/2 to Dp=0.90D/2, and a maximum width W within a range of W=0.75D/2 to W=0.90D/2, and wherein the maximum width W extends symmetrically about the centre line.

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=0.95D/4 to L1=1.2D/4. Each of the first and second lateral sides has a length LS1, LS2 within a range of D/4 to 1.3D/4. The first and second lateral sides diverge from each other in a direction radially outwards from the radially inner side.

A cutting insert is provided, comprising a top surface, a bottom surface, a plurality of side surfaces spanning therebetween, and a cutting edge formed at an intersection of the side surface and a forwardly-disposed portion of the top the surface. It further comprises a cooling cavity projecting into the insert, a top end thereof being disposed further forwardly than an open bottom end thereof. The cooling cavity defines at least one molding axis such that a solid element having the shape of the cooling cavity and completely inserted therein may be retracted intact therefrom along a linear path parallel to the molding axis. A circumscribing portion is formed on the side surfaces encircling the cutting insert. The circumscribing portion is formed parallel to the molding axis and has a non-zero height along its entire extent. The cutting insert does not extend beyond the circumscribing portion.

Disclosed is a hole cutter capable of reducing a cutting load applied to a carbide tip during hole machining and improving cutting efficiency and workability. The hole cutter includes a cylindrical body, and a plurality of carbide tips disposed along an edge of the body. The carbide tips include a first carbide tip, a second carbide tip, and a third carbide tip. Assuming a circle which has a center coinciding with the body center and is in contact with a sharp tip of an upper surface portion of the first carbide tip, the second carbide tip is formed so that the sharp tip of an upper surface portion thereof is positioned at an inner region of the circle, and the third carbide tip is formed so that the sharp tip of an upper surface portion thereof is positioned at an outer region of the circle.

Countersink guide assemblies and related methods. A countersink guide assembly includes a microstop cage and a stabilization guide. The microstop cage includes a cage sleeve, a cutter shaft, and a cutter that translates with respect to the cage sleeve as the cutter bores a countersink into a workpiece. The stabilization guide includes a guide body that defines a guide bore that receives the cage sleeve and a plurality of guide legs extending from the guide body. A method of boring a countersink into a workpiece includes positioning a microstop cage within a stabilization guide, engaging a workpiece with each of a plurality of guide legs, contacting the workpiece with a cage base, driving a cutter about a cage axis with a rotary driver, and transitioning the microstop cage to an extended configuration to bore the countersink into the workpiece with the cutter.