A thread cutting drill tool for metal cutting includes a cutting section having an axially extending chip flute and land, and a plurality of axially spaced teeth. Each tooth has an axially forward facing front flank and an axially rearward facing rear flank, a radially outward facing crest connecting the front flank and the rear flank, and a cutting edge. The cutting edge includes a set of crest cutting edges, each crest cutting edge being formed by an intersection of the crest of one tooth with the chip flute. The cutting edges include a set of front finishing edges and a set of rear finishing edges. Each front finishing edge is formed by an intersection of the front flank of one tooth with the chip flute. Each rear finishing edge is formed by an intersection of the rear flank of a tooth with the chip flute.

A tap and chaser are provided each having a cylindrical tool receiver connected to a threading section by a shaft. The receiver and shaft are of diameters sufficiently small to enter the bore hole and distribute any off axis load onto a number of internal threads of the bore hole to dissipate loading. The threaded section includes a group of longitudinal flutes. Each of the lands of the threaded section includes a novel cutting face, tooth angle and rake angle to advantageously allow for threading deep blind holes.

A process of forming a fastener with improved threading to resist multi-axial forces and off-axis loading scenarios is provided. The process may include placing first and second mill tools adjacent a shaft of the fastener having a proximal end and a distal end, rotating the shaft and the first and second mill tools, and translating the first and second mill tools along at least part of a length of the shaft to form: a first concave undercut surface oriented toward the proximal end, a first convex undercut surface oriented toward the distal end, a second concave undercut surface oriented toward the distal end, and a second convex undercut surface oriented toward the proximal end.

A multi-sectional drilling and tapping apparatus includes a shank, a drill and a tap that are made in one piece. The shank is formed at an end while the drill is formed at another end. The drill includes a small section formed between a tip and a large section. The drill further includes helical blades extending to the shank from the tip. The tap includes helical ribs each extending from a corresponding one of the helical blades and groups of tooth-shaped blades each evenly arranged along a corresponding one of the helical ribs. The tap includes a diameter larger than that of the large section of the drill.

A tap and chaser are provided each having a cylindrical tool receiver connected to a threading section by a shaft. The receiver and shaft are of diameters sufficiently small to enter the bore hole and distribute any off axis load onto a number of internal threads of the bore hole to dissipate loading. A central bore is provided for broken tool extraction. The threaded section includes a group of longitudinal flutes. Each of the lands of the threaded section includes a novel cutting face, tooth angle and rake angle to advantageously allow for threading deep blind holes.

Opposing undercut surfaces may be formed on a helical thread disposed about a shaft of a fastener by: rotating the shaft; translating a first cutting head medially toward the shaft along a first oblique trajectory of a first oblique cutting surface of the first cutting head; translating the first cutting head along a length of the shaft to form at least one of the opposing undercut surfaces on the helical thread; translating a second cutting head medially toward the shaft along a second oblique trajectory of a second oblique cutting surface of the second cutting head; and translating the second cutting head along a length of the shaft to form at least another one of the opposing undercut surfaces on the helical thread.

Provided is a thread mill that can reduce tilting of an internal thread to be machined, thus increasing the tool life. A thread mill includes a plurality of thread cutting edges that are circumferentially spaced apart on a front end side of an outer circumference of a tool body, and a plurality of end cutting edges formed at the front end of the tool body. A functional cutting edge portion that cuts a workpiece, and a non-functional cutting edge portion that is relieved toward an axial shank end relative to a trajectory of the functional cutting edge portion when the tool body is caused to make one rotation about an axis are formed on the plurality of end cutting edges.