The present disclosure provides a cutting insert that is economical and can be stably fixed to a tool body. A first edge line (10R) of a cutting insert (2) is a rectangle having a first side (11) and a third side (13) as long sides and a second side (12) and a fourth side (14) as short sides. Cutting edges are formed at the first side (11), the second side (12) and the third side (13); on the other hand no cutting edge is formed at the fourth side (14). At a second edge line (20R) having the same shape as the first edge line (10R), a sixth side (22) where a cutting edge is formed is opposite to the fourth side (14), and an eighth side (24) where a cutting edge is not formed is opposite to the second side (12). A peripheral side surface (30) includes a fourth side surface (34) facing the fourth side (14) and the sixth side (22). The fourth side surface (34) extends from a first end surface (10) to a second end surface (20) and is inclined in a direction from the second side (12) to the fourth side (14).

An orbital drilling device includes, on the same frame: a motor rotating a cutting tool on itself; a first, interior, eccentric, receiving the motor, mounted so as to be able to rotate; a second, exterior, eccentric, receiving the first eccentric, mounted so as to be able to rotate; a reference body, secured to the frame, receiving the second eccentric, mounted so as to be able to rotate; a first unit for driving the first eccentric; a second unit for driving the second eccentric, simultaneously with the rotation of the first eccentric; and a controller configured to reproduce any path of the cutting tool in the zone by continuous control of the angular offset between the first eccentric and the second eccentric.

A combination cutting and burnishing orbital drilling tool may include an elongate tool body including a cutting end and extending along a longitudinal axis. The tool body may include a burnishing portion spaced from the cutting end and configured to induce residual stress in a side wall of a hole without removing material. The tool body may further include a cutting portion interposed between the cutting end and the burnishing portion. The cutting portion may be configured to remove material from a workpiece, thereby creating the hole, during an orbital drilling process.

An example end mill includes a shaft, a cutting head positioned on one end of the shaft, and an edge relief cutting head positioned on the shaft spaced apart from the cutting head. The portion of the shaft between the cutting head and the edge relief cutting head has a diameter that is less than the diameters of the cutting head and the edge relief cutting head. The end mill is rotated around a longitudinal axis of the end mill and revolved around a central axis of a hole to be cut, with the longitudinal axis radially offset from the central axis, to cut the hole with the cutting head and cut an edge relief in a leading edge of the hole with the edge relief cutting head.

According to one implementation, an end mill for orbital drilling includes: a shank; a first cutting edge formed in a peripheral portion of the shank; and a second cutting edge formed in a bottom portion of the shank. At least a chamfered edge is formed on a first ridgeline between a first rake face and a first flank of the first cutting edge.

An orbital drill bushing adapter for use with a drill unit. In one embodiment, the orbital drill bushing adapter comprises a main body and locking arms. The main body includes a base member having an upper surface, a lower surface, and an external side wall that extends between the upper surface and the lower surface. The main body further includes a cylindrical spacer that projects from the lower surface of the base member, and is configured to fit in a drill hole of an orbital drill bushing. The main body includes a cylindrical hole that passes through the base member and the cylindrical spacer. The locking arms are pivotally coupled to the base member, and are configured to clamp the main body onto the orbital drill bushing.

Disclosed is a combination tool having a plurality of cutting elements. According to one embodiment, the combination tool comprises a drilling portion, a milling portion, and a boring portion. In this embodiment, the combination tool may perform a drilling operation, a milling operation, and a boring operation in quick succession with a single cutting tool. In another embodiment, the combination tool includes an additional cutting element such as a chamfering portion, which may perform a countersinking operation.

An orbital drill includes a drilling portion, a shank portion, and a neck portion between the drilling portion and the shank portion. The drilling portion includes one or more right-handed spiral flutes with cutting edges having a positive axial rake angle for positive cutting action while orbiting into a material. The right-handed spiral flutes have a positive radial and axial rake angle. The drilling portion also includes one or more left-handed spiral flutes located rearward of the one or more right-handed spiral flutes with cutting edges having a positive axial and radial rake angle for positive cutting action while orbiting back out of the material and removing any material left in the hole, thereby eliminating a separate reaming operation. A method of machining a workpiece using the orbital drill is also disclosed.

A mold machining method using an endmill, the contour of a cross section of the mold being concave and continuous in an area, a ratio of the maximum to the minimum of radius of curvature of the contour of a portion of the area (a first area) being 2 or greater, and a blade of the endmill having a second area where the contour of a cross section is similar to the contour of the first area, the method comprising the steps of: determining a spiral path of the endmill such that each point of the first area is machined by a portion of the second area, corresponding to said each point in the similarity, and a radial interval between the spiral tool path is maximized while keeping surface roughness of the machined mold at or below a predetermined value; and machining the mold along the path.

An orbital drill includes a drilling portion, a shank portion, and a neck portion between the drilling portion and the shank portion. The drilling portion includes one or more right-handed spiral flutes with cutting edges having a positive axial rake angle for positive cutting action while orbiting into a material. The right-handed spiral flutes have a positive radial and axial rake angle. The drilling portion also includes one or more left-handed spiral flutes located rearward of the one or more right-handed spiral flutes with cutting edges having a positive axial and radial rake angle for positive cutting action while orbiting back out of the material and removing any material left in the hole, thereby eliminating a separate reaming operation. A method of machining a workpiece using the orbital drill is also disclosed.