An automated computer-implemented method for generating commands for controlling a computer numerically controlled machine to fabricate an object from a workpiece, the method including the steps of selecting a maximum permitted engagement angle between a rotating cutting tool and the workpiece, selecting a minimum permitted engagement angle between the rotating cutting tool and the workpiece, and configuring a tool path for the tool relative to the workpiece in which the engagement angle gradually varies between the maximum permitted engagement angle and the minimum permitted engagement angle.

A rotary cutter for cutting damaged threads of a bolt includes a body rotatable about a rotating axis. The body includes a connecting end and an operative end. The body includes an inner periphery delimiting a cutting space extending along the rotating axis from the operative end towards but spaced from the connecting end. A width of the cutting space in a diametric direction perpendicular to the rotating axis gradually reduces from the operative end toward the connecting end to form a conic space. The body further includes at least one cutting blade disposed on the inner periphery. The at least one cutting blade includes a first cutting blade section and a second cutting blade section. The first cutting blade section is arcuate or rectilinear. The second cutting blade section is arcuate or rectilinear. The first and second cutting blade sections are not identical.

A rotational cutting tool includes a connecting end for engaging with a driving tool and a cutting end for engaging with the work piece. The connecting end and the cutting end rotate about the rotation axis upon rotation of the rotational cutting tool. An inner periphery of the cutting end defines a receiving space for receiving the work piece. The receiving space has a conic surface which extends radially and obliquely with respect to the rotation axis. The receiving space includes a first ridge forming at least one cutting edge for trimming the workpiece and at least one slot allowing trimmed pieces from the workpiece to exit from the receiving space. The first cutting edge extends radially and obliquely with respect to the rotation axis. The first cutting edge extends curvedly and has a curved contour.

A tool head for use with a modular shank tool includes at least two preforms. Each preform of the at least two preforms is made separately from the other preform of the at least two preforms from granular materials and then put together and jointly compressed and integrally bonded.

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.

A rotary cutter for cutting damaged threads of a bolt includes a body rotatable about a rotating axis and having a connecting end and an operative end. A first cutting blade is disposed on an inner periphery of the body facing a cutting space extending along the rotating axis from the operative end towards but spaced from the connecting end. The body further includes a virtual projection plane perpendicular to the rotating axis. A first virtual plane passes through the first cutting blade and extends perpendicularly to the virtual projection plane. A virtual circle and a first virtual reference line are located on the virtual projection plane. The first virtual reference line intersects the rotating axis and passes through an intersection of the first virtual plane and the virtual circle. An angle between the first virtual reference line and the first virtual plane is between 5 and 40.

A reaming tool includes a tool body having an axially rearward shank portion and an axially forward cutting portion, the forward cutting portion having at least one peripherally arranged cutting insert. The reaming tool also includes an inlet coolant channel formed in the tool body and an inlet opening at an axially rearward end of the shank portion. An outlet coolant channel is formed in the tool body and is in fluid communication with the inlet coolant channel, wherein the outlet coolant channel defines an outlet opening proximate to the cutting insert. In one particular aspect, at least a portion of the outlet coolant channel is non-linear. A method of making a component of the reaming tool by performing a printing operation on a substrate to form the component is also provided.

A reaming tool includes a tool body having an axially rearward shank portion and an axially forward cutting portion, the forward cutting portion having at least one peripherally arranged cutting insert. The reaming tool also includes an inlet coolant channel formed in the tool body and an inlet opening at an axially rearward end of the shank portion. An outlet coolant channel is formed in the tool body and is in fluid communication with the inlet coolant channel, wherein the outlet coolant channel defines an outlet opening proximate to the cutting insert. In one particular aspect, at least a portion of the outlet coolant channel is non-linear. A method of making a component of the reaming tool by performing a printing operation on a substrate to form the component is also provided.

A drill bit including a shaft which has a pyramidal shaped end defining a drill tip with a plurality of edges defining the pyramidal shape. One or more recesses are provided for directing away debris produced whilst drilling. At least one recess has a first portion extending along the shaft and a second portion having a first portion extending along the shaft and a second portion which extends along the drill tip. The second portion of the at least one recess extends along an edge of the drill tip.

A tool rest has a base, a tool holder rotatably supported on the base, and rotatably holding a tool, a rotational mechanism rotating the tool holder, a plurality of flexible linear members in which one ends of the plurality of linear members are connected with the tool holder and a winding device connected with the other ends of the plurality of linear members, and winding up the plurality of linear members by rotating when the tool holder is rotated by the rotational mechanism.