Orthopedic systems and methods for installing an implant and/or boring a bone bicortically. The system may include a drill having a proximal boring portion configured to bore a larger hole in a bone more efficiently when the drill rotates in a first direction compared to an opposite second direction, and a distal boring portion configured to bore a smaller hole in the bone more efficiently when the drill rotates in the second direction. The implant may be configured to be implanted at least partially in the bone, such that a first region of the implant is located in the larger hole and a second region of the implant is located in the smaller hole. In an exemplary method, the larger hole and the smaller hole may be bored in the bone's near cortex and far cortex, respectively, by a shaft and a nose of the drill rotated in opposite directions.

In this small-diameter drill bit, two cutting blades having main cutting blades, of which a difference between lengths are 0.04 mm or less, are formed on a tip of a double-margin drill bit body having a diameter of 2 mm or less and a margin length/diameter ratio of 3 or more. Two tip flank faces are formed such that a first extension line extending from a linear first intersecting ridgeline between a first tip flank face and a second tip flank face of one of the flank faces to the linear first intersecting ridgeline of the other flank face is located on a side in the drill bit rotation direction with respect to the other linear first intersecting ridgeline. A distance between the first extension line and the linear first intersecting ridgeline is in a range of 0.04 mm-0.08 mm.

Two discharge grooves (4) are formed in a drill (1). A cutting edge (5) is formed on a ridge section between an inner face (41) that faces a rotation direction (T) side of the discharge groove (4), and a flank (6). A thinning edge (7) is formed from an inner end (51) of the cutting edge (5) to the side of a chisel (9), by thinning processing, and further, a gash portion (8) is formed from an inner end (72) of the thinning edge (7), the gash portion extending in a circular arc shape and being connected to the discharge groove (4) further to an inner side in the radial direction than an outer peripheral surface (31). A circular arc groove (10) is formed in a section connecting a thinning face (71) and a gash face (81). The chips being cut by the thinning edge (7) are scooped up to the gash portion (8), are curled, and are discharged to the discharge groove (4). The chips are not likely to become caught by being provided with the circular arc groove (10). Since the gash portion (8) connects to the discharge groove (4) further to the inner peripheral side than the outer peripheral surface (31), the chips are cut relatively small.

Provided are a hole formation method enabling the formation of a high-quality hole even when a workpiece material is a difficult-to-machining metal material or a fiber-reinforced composite material and a drill bit used in the method. A drill bit includes at least one cutting edge and a face (a leading flank and a trailing flank) positioned in the vicinity of the cutting edge, and on the face, a recess exhibiting a prescribed planar shape (groove) is provided. A hole formation method includes a hole formation step of machining a portion to be processed of a workpiece material by means of drilling to form a hole while a lubricant material for assisting machining process is in contact with the portion to be processed, and in the hole formation step, the drill bit is used.

A drill is a long drill that is provided with a discharge groove having a helix angle of 25 degrees, in which a groove length is 30D or more. Thinning processing is performed on a leading end portion of the drill and a gash portion that is connected to the discharge groove further to an inner side in the radial direction than an outer peripheral surface. A circular arc groove is formed in a section connecting a thinning face and a gash face, and a chip discharge performance is improved. When forming a deep hole, in a guide hole forming process, a guide hole with an inner diameter d of D+0.03 mm or less and with a depth W of 3D or more, is formed (S2 to S6). In an insertion process, the drill is rotated in a reverse direction and is inserted into the guide hole to a position just before a bottom portion of the guide hole (S11 to S13). In a deep hole forming process, the drill is rotated in a positive direction, cutting is performed from the bottom portion of the guide hole, and a deep hole is formed (S16 to S18).

A drilling tool includes at least two chip flutes and a chisel edge with a thinned region. The thinned region merges continuously into the chip flutes in such a way that the thinned region forms the end of the respective chip flute in the region of the chisel edge.

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.

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.

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.

A cutting head rotatable about a first axis, comprising an intermediate portion and a tip portion. The intermediate portion has a plurality of leading edges defining a cutting diameter, and the tip portion has an axially forwardmost tip point and a plurality of front surfaces with outer and inner cutting edges. An outer rake surface adjacent to each outer cutting edge has a positive outer rake angle, and an inner rake surface adjacent to each inner cutting edge has a negative inner rake angle. Each outer rake surface is disposed on a head flute intersecting one of the leading edges, and each inner rake surface is disposed on a gash intersecting one of the head flutes. Each gash extends to a gash path end point located a first distance axially rearward of the tip point, and the first distance is greater than thirty percent of the cutting diameter.