A method for producing a cutting tool, in particular a drill bit, is specified wherein the cutting tool has a front end (F) at the front and a rear end (R) toward the rear, wherein a tool tip is formed on the front end (F), a point thinning is ground at the tool tip with a grinding tool, the point thinning being ground to be narrower toward the front than toward the rear. The point thinning is ground with a constant point thinning angle (AW). Furthermore, a corresponding cutting tool is specified.

According to one implementation, a drill includes the first cutting edges, the second cutting edges and a deflection reducer. The first cutting edges drill a prepared hole to a workpiece. The first cutting edges are formed in a tip side of the drill. The first point angle and each first relief angle of the first cutting edges continuously or intermittently decrease from the tip side toward a rear end side of the drill. The second cutting edges ream the prepared hole. The second cutting edges are formed at positions away in the rear end side from the first cutting edges. The second cutting edges have the second relief angles at a maximum diameter position. The deflection reducer reduces deflection of the second cutting edges. The deflection reducer is formed between the first cutting edges and the second cutting edges. The deflection reducer is inserted into the prepared hole.

The invention relates to a drill tip (2), comprising a center (4), at which a chisel edge (6) is arranged, and comprising a main cutting edge (8), which adjoins the chisel edge (6) and runs outward from the center (4). A rake angle is formed along the chisel edge (6) and the main cutting edge (8). The main cutting edge (8) has an inner portion (10), which adjoins the chisel edge (6) and is arranged within the center (4). The main cutting edge (8) has an outer portion (12), which outwardly adjoins the inner portion (10) and is arranged outside of the center (4). A point thinning (16) is formed on the drill tip (2), which point thinning is curved in such a way that the inner portion (10) runs arcuately from an outer edge of the center (4) toward the chisel edge (6). The invention further relates to a method for producing a drill tip (2) of this type.

For improving a drill, in particular a spiral drill, comprising a base body extending substantially longitudinally in a direction axial to a drill axis, said base body comprising a drilling portion, wherein a radially inward core region in relation to the drill axis and a radially outer region are provided in the base body in the drilling portion, and the drilling portion comprises a plurality of spiral-shaped recesses in the outer region, and arranged between each two spiral-shaped recesses is a wall part, it is proposed that the drill comprises at least four main cutting edges, in particular exactly four main cutting edge and/or the drill comprises at least three central cutting edge portions.

A cutting tool may include a body, a cutting edge, and a flute. The body may include a rotation axis and extend from a first end to a second end. The cutting edge may be located at the first end. The flute spirally may extend from the cutting edge toward a side of the second end. The cutting edge may include a first cutting edge and a second cutting edge extending from the first cutting edge toward an outer peripheral surface of the body in a front view. The flute may include a first thinning portion located continuously with the first cutting edge at a side of the first end, and a second thinning portion located continuously with the second cutting edge at a side of the first end. A thinning angle of the first thinning portion may be smaller than a thinning angle of the second thinning portion.

A drill according to a non-limiting aspect may have a body, a cutting edge, a rake face, and a groove. The cutting edge may have a curved chisel edge, a pair of first cutting edges, and a pair of second cutting edges. The second cutting edge may have a first portion extending from the chisel edge and a second portion extending from the first portion toward the first cutting edge. The rake face may have a first region extending from the first portion and a second region extending from the second portion. A first rake angle of the first region may be zero or a negative value. A second rake angle of the second region may be a negative value. An absolute value of the second rake angle may be greater than an absolute value of the first rake angle.

A drill includes a body. The body includes a first cutting edge, and a second cutting edge apart from the first cutting edge to the back end side relative to the first cutting edge and formed in a recess traversing an outer peripheral portion of the body. In a side view of the body in a first direction in which a distance between a center axis of the body and a first outer end of the first cutting edge is seen the longest, a second outer end of the second cutting edge is located at the center axis side relative to the first outer end of the first cutting edge.

A drilling insert has a central portion with a central axis, and three circumferentially spaced tip portions. Each tip portion has a first axis and two diverging first cutting edges with radially outermost cutting points defining a first circle lying on a tip plane perpendicular to the first axis and having a first cutting diameter. In a view along one of the first axes, a second circle having a second diameter circumscribes the drilling insert, and the first cutting diameter is at least sixty percent of the second diameter. A cutting tool rotatable about a tool axis with a tool cutting diameter includes the drilling insert, and a second cutting insert having a second cutting edge. One of the tip portions is operative having its first axis coaxial to the tool axis, and the second cutting edge extends radially outward of the first cutting diameter.

A drill includes a leading end portion. The leading end portion is flat and has at least two cutting blades extending from a rotation center toward outside in a radial direction. The each cutting blade includes an arc-shaped portion. An inside linear portion is formed in a linear shape and connects to one end of the arc-shaped portion on the rotation center side. An outside linear portion is formed in a linear shape and connects to another end of the arc-shaped portion on an opposite side to the one end. The arc-shaped portion has a cutting edge provided with an arc-shaped portion chamfered surface. The inside linear portion and the outside linear portion each has a cutting edge provided with a linear portion chamfered surface. A drill axis direction width of the arc-shaped portion chamfered surface is smaller than a drill axis direction width of the linear portion chamfered surface.

Provided is a method for manufacturing a sintered component, which can suppress occurrence of edge chipping when a through-hole is formed in a powder-compact green body and also has a good productivity. The method for manufacturing a sintered component includes a molding step of press-molding a raw material powder containing a metal powder and thus fabricating a powder-compact green body; a drilling step of forming a hole in the powder-compact green body using a drill; a sintering step of sintering the powder-compact green body after drilling, wherein the drill used for drilling has a circular-arc shaped cutting edge on a point portion thereof.