A method for producing a threaded hole in a workpiece with a thread tapping tool bit, which, at its drill bit tip, has a main cutting edge and a thread profile that trails in a thread tapping direction with at least one thread cutting tooth, wherein, in a thread tapping stroke, the main cutting edge produces a core hole, and, at the same time, the thread profile forms an internal thread at the inner wall of the core hole until a target thread depth is reached, and this is conducted with a thread tapping advance in the thread tapping direction and at a thread tapping rotational speed of the thread tapping tool bit synchronized therewith. After the thread tapping stroke, an oppositely directed reversing stroke is produced, in which the thread tapping tool bit is withdrawn out from the threaded hole in a reversing direction and, in fact, this is conducted with an opposite reversing feed.

A method for producing a threaded hole in a workpiece with a thread tapping tool bit, which, at its drill bit tip, has a main cutting edge and a thread profile that trails in a thread tapping direction with at least one thread cutting tooth, wherein, in a thread tapping stroke, the main cutting edge produces a core hole, and, at the same time, the thread profile forms an internal thread at the inner wall of the core hole until a target thread depth is reached, and this is conducted with a thread tapping advance in the thread tapping direction and at a thread tapping rotational speed of the thread tapping tool bit synchronized therewith. After the thread tapping stroke, an oppositely directed reversing stroke is produced, in which the thread tapping tool bit is withdrawn out from the threaded hole in a reversing direction and, in fact, this is conducted with an opposite reversing feed.

A torque-adjustable tapping apparatus includes a tap, a wrench and a torque-adjusting mechanism including a shell, a primary adjuster and a clutch. The shell is connected to the wrench. The shell includes an internally threaded section. The primary adjuster includes an externally threaded section engaged with the internally threaded section. The clutch includes an upper gear and a lower gear. The upper gear includes teeth extending from a lower face and at least one restraining cutout in a periphery. The lower gear includes teeth extending from an upper face and a connective rod extending from a lower face. The teeth of the lower gear are engaged with the teeth of the upper gear. The connective rod is connected to the tap. At least one screw is inserted in the restraining cutout through the screw hole. A spring is compressed between the primary adjuster and the upper gear.

A torque-adjustable tapping apparatus includes a tap, a wrench and a torque-adjusting mechanism including a shell, a primary adjuster and a clutch. The shell is connected to the wrench. The shell includes an internally threaded section. The primary adjuster includes an externally threaded section engaged with the internally threaded section. The clutch includes an upper gear and a lower gear. The upper gear includes teeth extending from a lower face and at least one restraining cutout in a periphery. The lower gear includes teeth extending from an upper face and a connective rod extending from a lower face. The teeth of the lower gear are engaged with the teeth of the upper gear. The connective rod is connected to the tap. At least one screw is inserted in the restraining cutout through the screw hole. A spring is compressed between the primary adjuster and the upper gear.

A method for producing a threaded bore in a workpiece with a tapping tool bit, which, at its drill bit tip, has a main cutting lip and a thread profile trailing in a tapping direction (I) with at least one thread cutting tooth, wherein, in a tapping stroke (G), the main cutting lip produces a core hole and, at the same time, the thread profile forms an internal thread at the inner wall of the core hole until reaching an intended thread depth (t.sub.G), specifically with a tapping feed (f.sub.G) in the tapping direction (I).

A method for producing a threaded bore in a workpiece with a tapping tool bit, which, at its drill bit tip, has a main cutting lip and a thread profile trailing in a tapping direction (I) with at least one thread cutting tooth, wherein, in a tapping stroke (G), the main cutting lip produces a core hole and, at the same time, the thread profile forms an internal thread at the inner wall of the core hole until reaching an intended thread depth (t.sub.G), specifically with a tapping feed (f.sub.G) in the tapping direction (I).

A method for producing a threaded hole in a workpiece with a thread tapping tool bit, which, at its drill bit tip, has a main cutting edge and a thread profile that trails in a thread tapping direction with at least one thread cutting tooth, wherein, in a thread tapping stroke, the main cutting edge produces a core hole, and, at the same time, the thread profile forms an internal thread at the inner wall of the core hole until a target thread depth is reached, and this is conducted with a thread tapping advance in the thread tapping direction and at a thread tapping rotational speed of the thread tapping tool bit synchronized therewith. After the thread tapping stroke, an oppositely directed reversing stroke is produced, in which the thread tapping tool bit is withdrawn out from the threaded hole in a reversing direction and, in fact, this is conducted with an opposite reversing feed.

A method for producing a threaded hole in a workpiece with a thread tapping tool bit, which, at its drill bit tip, has a main cutting edge and a thread profile that trails in a thread tapping direction with at least one thread cutting tooth, wherein, in a thread tapping stroke, the main cutting edge produces a core hole, and, at the same time, the thread profile forms an internal thread at the inner wall of the core hole until a target thread depth is reached, and this is conducted with a thread tapping advance in the thread tapping direction and at a thread tapping rotational speed of the thread tapping tool bit synchronized therewith. After the thread tapping stroke, an oppositely directed reversing stroke is produced, in which the thread tapping tool bit is withdrawn out from the threaded hole in a reversing direction and, in fact, this is conducted with an opposite reversing feed.

A method of configuring a machine (201) for production of a thread, having a pitch (227), on a workpiece (310), the machine (201) comprising: a tool (220) having a thread (223) centred on a first axis (250) and comprising one or more thread-producing peaks (225) for producing the thread having the pitch (227); and a tool holder (210) holding the tool (220), the method comprising: determining a first distance (441), in a first direction (260) parallel to the first axis (250), from a reference position (412) of the tool holder (210) to a first thread-producing peak (226) on the tool (220) when said tool (220) is held in the tool holder (210); and setting a first configuration (401) of the machine (201) wherein the reference position (412) of the tool holder (210) has a displacement (440) parallel to the first axis (250) from a reference position (411) of the workpiece (310) depending only upon: the determined first distance (441); a translation (443) parallel to the first axis (250) to account for an angular offset (340) between the first thread-producing peak (226) and a desired thread start position (311) on the workpiece (310); and an integer multiple (444) of the pitch (227).

A method for producing a tapped bore in a workpiece with a tap drill bit, which, at its drill bit tip, has a primary cutting edge and a thread profile trailing in a tap drilling direction. The method has a tap drilling stroke, in which the tap drill bit is driven into the workpiece with a tap drilling advance in the tap drilling direction and at a tap drilling rotational speed synchronized therewith, and the tool-primary cutting edge produces a core-hole bore, and the thread profile of the tool bit forms an inner thread at the inner wall of the core-hole bore. In the tap drilling stroke, shavings are produced, which are conveyed in a shavings discharge direction, which is oppositely directed to the tap drilling direction, out from the tapped bore and collide here with thread flanks of the inner thread that face the shavings that are discharged.