Abstract: A monitoring method and a monitoring system for a machine tool to machine a workpiece are provided. The monitoring method includes the following steps. First, a vibration signal of a spindle of the machine tool is detected. Next, a vibration feature value of the vibration signal is obtained. Whether the vibration feature value exceeds a threshold condition is determined, wherein the threshold condition is determined by a training model based on a predetermined surface quality of the workpiece. When the vibration feature value exceeds the threshold condition, a machining parameter of the machine tool is adjusted.

Abstract: A boring tool holder has a base member and a cutting insert holding member. The base member has a first main surface and a second main surface opposite to the first main surface. The cutting insert holding member is contiguous to the base member on the first main surface, and disposed in a circumferential direction of the base member as viewed in a direction from the first main surface toward the second main surface. A cross-sectional area of the base member in a cross section perpendicular to the direction from the first main surface toward the second main surface and intersecting the base member is larger than a cross-sectional area of the cutting insert holding member in a cross section perpendicular to the direction from the first main surface toward the second main surface and intersecting the cutting insert holding member.

Abstract: An elongated tool holder includes a mass housing portion having a housing peripheral surface, an outer sleeve having a sleeve hole wall surface, and an anti-vibration arrangement. An elongated groove is formed in one of the housing peripheral surface and the sleeve hole wall surface. In an assembled state of the tool holder, the groove, which is located at a common interface of the housing peripheral surface and the sleeve hole wall surface, forms a groove coolant channel. The groove coolant channel forms part of an overall tool holder coolant channel which is spaced apart from the anti-vibration arrangement, and thus isolates the coolant from the anti-vibration arrangement. A cutting tool incorporates the tool holder.

Abstract: Cutting tool holders are disclosed that include vibration dampening elements. The vibration dampening elements may extend parallel to a longitudinal plane of the cutting tool holder. The vibration dampening elements allow the cutting tool holders to have a smaller width while still providing higher grooving depth.

Abstract: Rotatable assembly (10) having one end (12) adapted to be secured to a rotatable support for rotating the rotatable assembly (10) about a rotational axis (28), the rotatable assembly (10) comprising: a main body (18) having a cavity (56); a damping mass (38) arranged within the cavity (56) and movable in radial directions (30), substantially perpendicular to the rotational axis (28), relative to the main body (18); a damping structure (36) arranged to support the damping mass (38) relative to the main body (18) and arranged to damp vibrational movements of the damping mass (38) relative to the main body (18) in the radial directions (30); wherein the damping structure (36) comprises a plurality of spring elements (40); and wherein each spring element (40) has a flat appearance.

Abstract: A rotary cutting tool includes a tool body including a chip flute portion having a plurality of helical chip flutes separated by lobes. In one aspect, a tunable vibration absorber assembly is disposed within a cavity formed in the chip flute portion. In another aspect, the tunable vibration absorber assembly is disposed within a cavity of a replaceable cutting head. In each aspect, the tunable vibration absorber assembly includes one or more tunable absorber masses, a resilient material between the one or more absorber masses and the cavity, and one or more connecting members for preventing relative angular displacement of the one or more tunable absorber masses. The one or more tunable absorber masses are suspended only by the resilient material, thereby enabling the tunable vibration absorber assembly to be tuned to a desired frequency for suppressing torsional vibration of the rotary cutting tool during a cutting operation.

Abstract: A damper assembly for use with a non-rotating tool holder includes a hollow ram for supporting a non-rotating tool and a damper assembly mounted in the hollow ram for absorbing vibrations of the ram. The damper assembly includes a front plate and a rear plate, an upper tie rod and a lower tie rod extending between the front plate and the rear plate, and a damper mass mounted between the front plate and the rear plate. Ring dampers are mounted between the damper mass and the front and rear plates, and suspension springs are mounted between the upper tie rod and the lower tie rod. The suspension springs carry the weight of the damper mass so that the ring dampers do not have to carry the weight of the damper mass, and the damper mass is free to respond to vibrations in the ram.

Abstract: A tool body and a tool for cutting machining, wherein the tool body extends in an axial direction and at least a portion of the tool body is formed with a solid outer jacket encasing a core structure. The core structure includes a three-dimensional open lattice structure attached to the outer jacket and made of a lattice structure material. The core structure further includes a filling structure of a solid phase filling material that is different from the lattice structure material, wherein the filling structure surrounds the lattice structure. The lattice structure and the outer jacket are manufactured using additive manufacturing and the filling material is added to the lattice structure in the form of a liquid or a powder, which is thereafter solidified.

Abstract: The present application relates to a cutting tool (2), in particular a boring bar (2) for machining holes (16) separated from each other in an axial direction (4) by a given spacing distance (a), comprising a main body (10) extending in an axial direction (4) with an axis of rotation (R) with at least one cutting element (12), as well as with a number of guide elements (14) for guiding the main body (10) within a guide hole (16A), wherein the guide elements (14) for the axis of rotation (R) are separated by a guide radius (r1), wherein viewed in a cross-section, the main body (10) is divided into a functional region (19) and an eccentric region (20), wherein the cutting elements (12) and the guide elements (14) are arranged distributed over the circumference of the main body (10) over an angular region (?) of less than 180°.

Abstract: An NC unit calculates the phase difference in chatter vibration during working on the basis of detection result of sound produced by working a workpiece by an end mill, increases the number of rotations of the end mill by a predetermined number if the phase difference is smaller than a first phase difference threshold, and decreases the number of rotations of the end mill by a predetermined number if the phase difference is larger than a second phase difference threshold. Further, if the phase difference is between the first phase difference threshold and the second phase difference threshold, the NC unit finds the resonance frequency of a machine tool by multiplying a chatter frequency by a correction factor that changes according to the chatter frequency, and calculates the number of rotations of the end mill on the basis of the resonance frequency, to obtain stable working with suppressed chatter vibration.

Abstract: A damper assembly for use with a non-rotating tool holder includes a hollow ram for supporting a non-rotating tool and a damper assembly mounted in the hollow ram for absorbing vibrations of the ram. The damper assembly includes a front plate and a rear plate, an upper tie rod and a lower tie rod extending between the front plate and the rear plate, and a damper mass mounted between the front plate and the rear plate. Ring dampers are mounted between the damper mass and the front and rear plates, and suspension springs are mounted between the upper tie rod and the lower tie rod. The suspension springs carry the weight of the damper mass so that the ring dampers do not have to carry the weight of the damper mass, and the damper mass is free to respond to vibrations in the ram.

Abstract: An air balance mechanism includes a plate part, fixed shafts, and movable cylinders. A flange is provided at one end of each of the fixed shafts. The movable cylinders are movable relative to the fixed shafts. A space is formed below a lower surface of the flange. Further, the air balance mechanism includes fixing bolts and adjusting bolts. The fixing bolts fix the flange and a plate part at positions different from the space. The adjusting bolts are inserted into the plate part through the space for allowing the postures of the fixed shafts to be adjustable.

Abstract: A vibration analysis device calculates a vibration cycle which occurs during a period in which a workpiece is processed by a machine tool, and includes a tangential velocity calculation unit which calculates a velocity in a tangential direction of a movement path of a processing point by using positional information of a drive axis. The vibration analysis device comprises a movement distance calculation unit which calculates a first movement distance of the processing point on the movement path by using the velocity in the tangential direction. The vibration analysis device comprises a vibration cycle calculation unit which calculates a vibration cycle corresponding to streaks on the basis of previously measured streak intervals on the workpiece and the first movement distance of the processing point.

Abstract: A waveform display device includes a position information acquisition unit for acquiring position information of a drive shaft of a machine tool in a time series manner, a time designation unit for designating a time section that is a display target in a time series of the position information, a tangent direction speed calculation unit for calculating a tangent direction speed of a tool tip end point of the machine tool based on the position information and configuration information of the machine tool, a distance calculation unit for converting the time section into a distance between two points on a machined surface of the machine tool based on the tangent direction speed, and a display unit for displaying the distance between the two points.

Abstract: A rotary cutting tool has a central, longitudinal axis. One or more internal balancing features are disposed within a cavity of the rotary cutting tool. Each internal balancing feature includes a balancing mass suspended within the cavity by a spring-like element, and an adjusting screw for effecting radial movement of the balancing mass. Each internal balancing feature can be integrally-formed with the rotary cutting tool using a 3-D printing technique. The rotary cutting tool can be any rotary cutting tool, such as a milling cutter, a boring bar, and the like. The internal balancing features are arranged at predetermined locations within the rotary cutting tool to enable static and/or dynamic balancing of the rotary cutting tool.

Abstract: A side milling cutter for slot cutting is provided whose vibration can be damped even in cases where a vibration mode of the cutter generates plural nodes in a cutting part. A side milling cutter for slot cutting of the present invention includes a disc-shaped cutter and a plurality of cartridges as cutting edges provided at a predefined interval in a circumferential direction along an outer circumference of the disc-shaped cutter. The disc-shaped cutter cuts a predefined slot on a workpiece using the cartridges by circumferentially rotating. The disc-shaped cutter internally includes a plurality of vibration damping structures in the circumferential direction on a disk surface of the disc-shaped cutter.

Abstract: A toolholder includes a cutting tool mounted to a head attached to a collar at a first end of the toolholder. A shank is located at a second, opposite end of the toolholder. A central cavity extends inwardly from the first end toward the shank. A viscous fluid inertia mass damper is disposed within the central cavity. The viscous fluid inertia mass damper includes an absorber body having a first end, a second end opposite the first end, a fluid reservoir formed in the damper body for containing a viscous fluid, and a plurality of apertures formed in the damper body for allowing the viscous fluid to flow from the fluid reservoir and through the apertures to suppress vibration of the toolholder. A method for suppressing vibrations in a toolholder is also disclosed.

Abstract: A cylindrical calibration head for the drilling of a shaft, includes three flutes arranged evenly around the circumference so that they are spaced one from the next by an angle of 120° with respect to a rotation with respect to the axis of the calibration head, the flutes allowing for the removal of chips and the passage of lubricant during drilling, each of the flutes including a machining insert of which the position in the flute can be adjusted using an adjusting cartridge.

Abstract: An apparatus includes vibration data obtainer 30 obtaining data on vibration caused by a tool in cutting, a vibration frequency calculator 22 calculating a vibration frequency of the tool by analyzing the obtained vibration data, a regenerative chatter detector 23 detecting whether regenerative chatter occurs by comparing the calculated vibration frequency of the tool with a spindle rotation number, and a spindle rotation controller 24 gradually decreasing or increasing the spindle rotation number when occurrence of regenerative chatter vibration is detected, and a stable rotation number calculator 25 monitoring variation of the vibration frequency of the tool and determining a spindle rotation number when the variation of the vibration frequency exceeds a predetermined reference value to be a stable rotation number.

Abstract: To make it possible for bores (16) that are in line with one another to be efficiently worked by means of a boring bar (2), the boring bar has a main body (10) with an axis of rotation (R) and a number of cutting elements (12, 12A) at intervals from one another in the axial direction (4) and also guiding elements (14) for guiding the main body (10) in a guiding bore (16A). The guiding elements (14) are kept at a distance from the axis of rotation (R) equivalent to a guide radius (r1). The main body (10) is divided into a functional region (19) and an eccentric region (10), wherein the cutting elements (12, 12A) and the guiding elements (14) are arranged such that they are distributed around the main body (10) over an angular range (a) of less than 180°. Furthermore, the circumferential side (22) of the main body (10) can be passed eccentrically through a respective bore (16, 16A) of which the unworked tube radius (r2) is less than the guide radius (r1).

Abstract: Embodiments are directed to tunable damper embodiments and methods of using the same for damping resonant and non-resonant vibrations present within an object that the tunable damper is secured to. In some cases, the tunable damper may be tuned before, during or after being secured to an object.

Abstract: A holder and a cutting tool with the holder including an insertion hole at a front end part thereof, and a cutting insert that includes a cutting edge part and a shank part. The shank part has substantially a rod shape. A part of the shank part is immovably located in the insertion hole. The front end part of the holder includes a first curved surface part that becomes wider from a front end toward a back side when viewed from a side thereof. The first curved surface part includes: a curved line that extends from an edge of an opening of the insertion hole toward the back side; or a straight line that extends from the edge of the opening of the insertion hole and connects to a curved line that extends continuously from the straight line toward the back side without an angular part.

Abstract: A numerical control machine-tool includes: a ground-resting base plate; a movable supporting column rising cantilevered from the base plate in a substantially vertical direction and movable horizontally on said base plate; a first electronic-controlled drive assembly for moving the supporting column along the base plate; a head-carrier slide fixed in vertically sliding manner in a straight longitudinal slit extending along the front face of the supporting column parallel to the longitudinal/vertical axis of the supporting column; a second electronic-controlled drive assembly for moving the head-carrier slide along the supporting column; a straight supporting beam inserted in an axially sliding manner into the head-carrier slide and cantilevered juts out from the front face of the supporting column while remaining substantially parallel to the ground; and a third electronic-controlled drive assembly for moving the supporting beam forwards and backwards with respect to the head-carrier slide parallel to the bea

Abstract: A tuned or tunable boring tool includes a boring bar defining an elongated cavity therein. A distal end of the boring bar is configured to support a tool or cutting insert. The boring tool further includes a dynamic vibration absorber inserted within the elongated cavity of the boring bar. The dynamic vibration absorber includes a mass that vibrates in conjunction with vibration of the boring bar. The mass has a proximal end and a distal end. The dynamic vibration absorber further includes at least one resilient proximal support positioned adjacent to and supporting the proximal end of the mass and at least one distal resilient support positioned adjacent to and supporting the distal end of the mass. The at least one proximal support and at least one distal support have a different stiffness.

Abstract: A vibration damping mechanism allows increase of an absorption amount of vibration energy, with less possibilities of increase in the manufacture cost of a vibration damping weight and of reduction in the strength of a shaft section. Within a cylindrical hollow portion formed inside the shaft section, there are accommodated a plurality of weight members divided from each other along the circumferential direction about the axis of the hollow portion. An urging member is provided for urging the weight members toward the axis such that dividing faces of adjacent weight members are brought into surface contact with each other.

Abstract: To provide a tool holder that is capable of exerting a vibration-minimizing effect in a reliable manner using a simple configuration and that is extremely useful for practical application.

Abstract: The present invention relates to a bit for processing the inside diameter of a work material, the bit having on the outer surface of a shank a vibration preventing structure comprising a vibration absorption body made of a silicone material, and a hollow wire rod, thereby absorbing the vibration generated from a machine tool, preventing resonance generated between the work material and a tool, and thus, enabling the implementation of a slickenside from ultra-precision machining.

Abstract: The table on which a workpiece is put can travel on a guide rail mechanism relative to a working head with a cutting tool mounted thereon. The table is connected through a nut to a ball screw part to move in an axial direction thereof as the ball screw part rotates. One end of the ball screw part is supported by a bearing and the other end is connected to a servomotor to be rotationally driven. A hollow part is provided in the table to receive therein a damper mechanism part, which comprises a spring, a damper, and a weight, the table and the weight being arranged to enable traveling separately on guide rails. Thereby, even when the workpiece is heavy, the weight can move relative to the table to effectively damp vibrations of the table in a feed direction.

Abstract: Device and method for milling of materials including a milling cutter body including a first end portion and an opposite second end portion. The first end portion is connected to a rotatable spindle and the second end portion is provided with at least one cutting edge. The milling cutter body defines a longitudinal axis and is provided with an axial recess, wherein at least one mass element is arranged in the recess. The axial position of the mass element in relation to the milling cutter body is tuned by use of tuning members included in the device for the tuning of the natural frequency of the device. The mass element is axially locked in relation to the milling cutter body by use of lock members included in the device, in order to optimize the natural frequency of the device for the milling operation in question.

Abstract: A milling tool assembly has a replaceable cutter and a reusable shank connected to the cutter with a detachable joint. The joint may be, for example, a threaded connection. An intermediate alignment sleeve made of an elastic or semi-elastic material, is positioned between the cutter and the shank about the axis of rotation of the shank.

Abstract: A method and apparatus may be provided for performing an operation on a workpiece. A tool holder with a tool and the workpiece may be positioned relative to each other. The tool holder may be attached to a machine. The tool may have a sleeve and a number of cutting features. The sleeve may have a first end, a second end, a surface, and a channel with an opening at the first end of the sleeve and an opening at the second end of the sleeve. The sleeve may receive at least a portion of a rod for the tool holder in the channel. A stiffness of the sleeve may be greater than a stiffness of the tool holder. The number of cutting features may be associated with the surface of the sleeve. The operation may be performed using the tool holder with the tool on the workpiece.

Abstract: A damping tool holder, such as a boring head, a chuck, or a milling cutting arbor, integrates a damping device (2), in the form of an elongated body. The damping device (2) is housed in a mounting body (3), connected by one end to the tool-holder body (1) and having at its other end an end fitting (4) for mounting a tool, whereby the mounting body (3) is equipped with at least one lubricant feed pipe (32), emptying at its front end into the end fitting (4) for mounting a tool and connected at its other end to a circular groove (102) for distributing lubricant that is provided on the front surface of the tool holder (1).

Abstract: The present invention provides an appliance for chip removal applications comprising a vibration-damping material wherein the vibration-damping material is a material arranged by nano-dimensional cluster form. The present invention additionally provides a method for manufacturing said appliance. The present invention provides also an appliance obtainable by said method. Additionally the present invention provides an article or work piece for use in an appliance for chip removal applications. Also a computer program is provided for controlling the above method.

Abstract: The damping property of a rear rolling bearing (133) is adjusted by controlling a damping force that is applied by damping application means (5, 134) based on, for example, the type of a tool (T). Thus, it is possible to provide the optimum damping properties for various tools that differ in natural vibration, and to suppress the generation of chattering of the various tools. As a result, it is possible to increase the cut amount per unit time to increase the productivity.

Abstract: The invention relates to a tool head having a main body (2) that is rotatable about a tool head axis (5), a slide (6) for holding a cutting tool, said slide (6) being guided on the main body (2) in a slide guide (8) in a linearly moveable manner transversely to the tool head axis (5), and a clamping device (48) for clamping the slide (6) on the main body (2). According to the invention, it is proposed that the clamping device (48) has a clamping body (50) that is adjustable parallel to the tool head axis (5), said clamping body (50), in a clamping position, pressing a sliding face (46) of the slide (6) against a guiding surface (44) of the slide guide (8) with a clamping force (FN) being introduced.

Abstract: A method and apparatus may be present for performing an operation on a workpiece. A tool holder with a sleeve and workpiece may be positioned relative to each other. The rod tool holder may be attached to a machine and may have a first stiffness. The sleeve may have a channel and a second stiffness. The channel may be configured to receive at least a portion of the rod. The operation may be performed using the rod with the tool on the workpiece.

Abstract: A damper includes at least one substantially longitudinal damping body with two end surfaces and one substantially longitudinal surface between. The damping body is placed in a substantially longitudinal cavity, which includes a cavity surface, with a damping fluid that includes a liquid and a gas. At least one of the cavity surface, end surfaces or longitudinal surface is broken, and the damping body can pulsate in the cavity when the damper is in operation.

Abstract: A rotary cutting tool includes a cutter body having a head, a shank, and a cavity extending along a central, longitudinal axis of the cutter body. The head includes at least one cutting insert mounted in a pocket adjacent to a chip groove. A vibration damping device is disposed within the cavity. The vibration damping device includes a stop member, a threaded fastener, weight elements, and a biasing member. At least one, if not all of the weight elements have different outside diameters to cause the weight elements to vibrate in the cavity at different frequencies. At least some of the frequencies of the weight elements are different than a fundamental chatter frequency of the cutting tool, thereby dampening vibration of the rotary cutting tool during a machining operation.

Abstract: A module for on-line vibration detection and adjustment and machining center using the same are provided in the present invention, wherein the module is disposed at the machining center having an interface of feedrate override and an interface of spindle override and the inverter. The module comprises at least one vibration sensor for detecting the vibrating status of the machining center, thereby generating corresponding at least one sensing signal and a processor for processing the at least one sensing signal so as to generate a spindle adjusting signal for the interface of spindle override and the inverter and a feedrate adjusting signal for the interface of the federate override. The computer numerical controller receives the spindle adjusting signal and the feedrate adjusting signal from the interface of the spindle override and federate override respectively and accordingly controls the feedrate and spindle rate of the machining center.

Abstract: The invention concerns a boring tool comprising a main tool body and a tool holder which is adjustable relative thereto, as well as a counterweight coupled to the tool holder in such a way that upon a movement of the tool holder in one direction a movement of the counterweight occurs substantially in the opposite direction, wherein both the tool holder and also the counterweight are respectively arranged at least in part in a bore in the main tool body. To provide a boring tool of the above-mentioned kind which is suitable in particular for high rotary speeds, which is advantageous in terms of manufacture and which in addition provides a reliable precise balancing function, it is proposed in accordance with the invention that the main tool body has a clamping device, by means of which the main tool body can be elastically deformed so that both the tool holder and also the counterweight are respectively clamped in the bore.

Abstract: A vibration damper for a drill tube of a hole machining apparatus includes a closed loop bi-directional adjustment mechanism, which operates from a single side of the damper. The closed loop mechanism ensures that the position of the clamping sleeve has a one-to-one relationship with the adjustment mechanism, which enables controlled adjustment of the clamping force to be performed. Locating the adjustment mechanism at one side of the clamping sleeve facilitates re-tooling, e.g. replacing the clamping sleeve if a larger diameter drill tube is to be used.

Abstract: A toolholder includes a body portion having an exterior surface and a dynamic absorber mounted on the exterior surface of the body portion. The dynamic absorber includes a rigid support member, a cover member, and an absorber mass disposed within a cavity formed by the rigid support member and the cover member. A first resilient support member is disposed between the rigid support member and the absorber mass, and a second resilient support member is disposed between the cover member and the absorber mass. The dynamic absorber is tuned by moving the cover member relative to the rigid support member. A method of suppressing vibrations of the toolholder includes externally mounting the dynamic absorber on the exterior surface of the toolholder.

Abstract: A boring head comprises a housing disposed about a central longitudinal axis and a movement transmission mechanism disposed at least one of on or in the housing. The housing includes a first end adapted to be coupled to a machine tool and an opposite second end having a cutting insert movably coupled thereto. The movement transmission mechanism comprises a rotatable member mounted to be rotatable relative to the housing, a balancing mass, and a main shaft disposed in the housing. The main shaft is rotatable about the longitudinal axis and operationally coupled to the ring, the balancing mass, and the cutting insert. Rotation of the rotatable member a predetermined amount causes movement of the cutting insert a corresponding predetermined amount in a first radial direction with respect to the longitudinal axis and movement of the balancing mass a corresponding predetermined amount in a second radial direction opposite the first radial direction.

Abstract: A tool holder includes a drawing screw and a stopper member. The drawing screw is positioned in an intermediate hole. A rear end face of a head of the drawing screw faces a boundary wall surface, and a top end of a shaft of the drawing screw is screwed in a rear end of a collet. The stopper member is positioned in an annular space between an outer peripheral surface of the shaft of the drawing screw and an inner peripheral surface of the intermediate hole. The stopper member faces a front end face of the head of the drawing screw, and limits movement of the head toward a top end of the tool holder. The drawing screw and the stopper member are inserted and assembled from a top end opening of a collet holding hole.

Abstract: A tool holder is provided that prevents chattering in a large-sized cutting tool. A tool holder 1 includes an anti-vibration device provided in a radially outer portion of a body. The anti-vibration device has a ring-shaped first anti-vibration member and a second anti-vibration member. The anti-vibration device is fixed to the body together with a cutting tool T1 by means of a bolt. Four O-rings are arranged on both sides of the first anti-vibration member, and the damper property is adjusted by pressing a pressing plate with adjuster bolts. An appropriate gap is formed between the first anti-vibration member and the body and between the first anti-vibration member and the second anti-vibration member.

Abstract: In one advantageous embodiment, an apparatus may comprise a housing having a first end, a second end, and a number of dimensions. Also, the apparatus may comprise a inner cylinder extending through the housing from the first end to the second end in which the inner cylinder is configured to receive a tool at the first end and is configured to a engage a tool holder at the second end in which the number of dimensions of the housing is configured to reduce vibrations during a machining operation.

Abstract: A tool holder (10) for a tool which can rotate about an axis of rotation (D) comprises a clamping shank (18) which, in an end shank region, has a clamping formation (14) with an accommodating opening (16) which is central in relation to the axis of rotation (D) and is intended for accommodating a retaining shank of the tool, there being provided, on the lateral circumference of the accommodating opening (16), at least one clamping surface for securing the retaining shank of the tool with press-fit action. According to the invention, on an axial section which forms an axial bracing section (VA), the tool holder (10) has a bracing arrangement (20) which, at least during operation of the tool holder (10), subjects the tool holder (10) to a bracing force (Vk) with a bracing force component (Vk) acting in the axial direction.

Abstract: A method to adjust a modal property of a material removal tool without changing a projection length of the material removal tool is disclosed. Adjusting substantially aligns a characteristic frequency of the material removal tool with a rotation speed of a spindle of a machine tool. A material removal tool employing the method and a method to machine metal are also disclosed.

Abstract: The invention concerns a boring tool comprising a main tool body and a tool holder which is adjustable relative thereto, as well as a counterweight coupled to the tool holder in such a way that upon a movement of the tool holder in one direction a movement of the counterweight occurs substantially in the opposite direction, wherein both the tool holder and also the counterweight are respectively arranged at least in part in a bore in the main tool body. To provide a boring tool of the above-mentioned kind which is suitable in particular for high rotary speeds, which is advantageous in terms of manufacture and which in addition provides a reliable precise balancing function, it is proposed in accordance with the invention that a tool holder and a counterweight are arranged in the same bore in the main tool body.

Abstract: A shrink-fit chuck tool holder which comprises: clamping means which are provided centrally with respect to an axis of rotation of the tool holder for holding a shank of a rotary tool, and which define a receiving opening for the shank. The clamping means can be displaced in the radial direction between a release position for insertion or removal of the shank and a clamping position. The clamping means are assigned a clamping surface with a cylindrical contour which, in the clamping position, bears against the outer circumferential surface of the shank. The clamping surface has a helical groove surrounding the axis of rotation or a multiplicity of annular grooves surrounding the axis of rotation, which as seen in the direction of the axis of rotation project towards the axis of rotation and the roof surfaces of which form the clamping surface.