In this drill, a wall face of a chip removal groove includes a first wall face having a concave curve shape and a second wall face having a straight line shape in a cross section orthogonal to an axis of the drill main body, an extension line of a straight line of the second wall face extends in a direction opposite to a drill rotation direction as the straight line of the second wall face goes to an outer periphery side of the drill main body with respect to a radius line connecting an outer peripheral end of the second wall face and the axis with each other, the cutting edge includes a first cutting edge having a concave curve shape and a second cutting edge having a straight line shape which intersects with the first cutting edge at an obtuse angle.

A drilling tool, in particular a spiral drill, has a drill longitudinal axis, at least two flutes extending at a twist angle with respect to the drill longitudinal axis, webs formed between the flutes, and lands formed on a lateral surface of the webs. Guide rings are at least partially formed on the lands. The guide rings extend at an angle different from the twist angle to the drill longitudinal axis. At least one guide chamfer is formed on at least one land in addition to the guide rings. The guide chamfer extends parallel to the twist angle and in front of the guide rings with respect to the direction of rotation of the drilling tool.

A drill bit that serves to remove mineral materials and that consecutively has on a longitudinal axis (6) a drill head (2), a helix (3), an insertion end (4) and an impact surface (7) on the end face of the insertion end (4) that faces away from the drill head (2) and that serves to absorb impact along a direction of impact (8), is provided. The drill head (2) has at least two cutting edges (13) and at least two blades (20). The cutting edges (13) each have a cutting face (16) and a free face (17).The blades (20) run parallel to the longitudinal axis (6) and adjoin the cutting edges (13). The blades (20) each have a radially projecting tooth (24) that adjoins the cutting face (16), whereas it adjoins the free face (17) either only partially or not at all. The axial dimension (29) of the tooth (24) is smaller than the axial dimension (25) of the blade (20).

A rotary tool according to a non-limiting aspect includes a body having a rotation axis and extending from a first end to a second end. The body including: a first part including the first end; a second part located closer to a second end than the first part and having a larger outside diameter than the first part; a cutting edge located at a side of the first end; a ridge portion located in the first part and the second part, connected to the cutting edge and helically extending from the cutting edge toward the second end; and a flute located along the ridge portion. The flute includes: a first flute located at the first part and having a first helix angle; and a second flute located at the second part and having a second helix angle. The second helix angle is smaller than the first helix angle.

The drill comprises a base body, which extends in the axial direction along an axis of rotation and rotates about the axis of rotation in a direction of rotation during operation. Into the base body are incorporated flutes and between consecutive flutes is formed a rear surface, which extends, in relation to the direction of rotation, from a leading flute to a trailing flute. On the rear surface in the region of the leading flute, a guide chamfer and a support chamfer spaced apart from it in the direction opposite the direction of rotation are formed, wherein the support chamfer, as radially outermost region, forms a support edge for a merely linear support.

A drill device includes a drill tip and a drill body having a rear portion. The drill tip includes at least a first clearance surface and the drill body includes at least a first land having a margin. An edge is disposed between the first clearance surface and the margin. A textured area having a plurality of recesses extends along at least a portion of the margin, in the direction of the rear portion of the drill body, from a position of 200 m from the edge, from a position on the least first clearance surface, or from a position therebetween.

A rotary cutting tool including a polycrystalline diamond material of the invention includes: a tool body rotated about an axis with a carbide substrate made of cemented carbide and a flute provided at a tip portion thereof; a PCD layer sintered integrally with the carbide substrate, provided on an inside face of the flute facing in a rotation direction; and a cutting edge provided on the PCD layer to have the inside face as a rake face, in which a margin portion continuous with a rear side of the flute in the rotation direction is formed on an outer periphery of the tip portion, the cutting edge is formed at a ridge portion of the rake face, and a thickness of the PCD layer is to 1 times a width of the margin portion.

The radial run-out tool (2), particularly a drill or a cutter, has a basic body (12) extending in an axial direction (4) and comprises at least two chip grooves (14), to which a guide chamfer (22) is connected in the rotational direction (24), with a ridge (15) being formed between them. A radial clearance is connected to the guide chamfer (22). In order to enable simple and economical production of such type of radial run-out tool (2), an unprocessed rod (30) is ground non-concentrically, in a first process step, such that a radius (R) of the unprocessed rod (30) varies, depending on the angle, between a maximum radius (R2) and a minimum radius (R1). In a second process step, the chip grooves (14) are grounded down such that the guide chamfers (22) are formed at the positions with the maximum radius (R2) and the radius (R) is subsequently reduced downstream of the respective guide chamfer (22) in order to form the radial clearance (28).

A step bit according to some embodiments includes a body including one or more flutes having a cutting edge configured to cut a hole in a workpiece, and a plurality of steps provided on the body. The steps progressively increase in diameter from a first distal step to a terminal proximal step. One or more of the steps have first and second lands. An outer diameter of the first land is less than the outer diameter of the second land. A length of the first land is less than a length of the second land.

A drill in which: a chip discharge groove is formed in an outer periphery of an edge portion serving as a leading end side portion of a drill body; and a cutting edge is formed in an intersecting edge between a rake surface of a leading end side region and a leading end flank of the edge portion, the drill comprising a margin portion, a shoulder portion and a web thinning portion, wherein: the cutting edge comprises, in order from a rotation center, a first cutting edge portion, a second cutting edge portion, a shoulder cutting edge portion, and a margin cutting edge portion; the honing width gradually decreases from the boundary P1 toward the position P2; and the conditions represented by expression (1): honing width of second cutting edge portion?R1 and expression (2): 2.0<R1/R2<5.0 are satisfied.