WO2022234756A1 - Holder, cutting tool, and method for manufacturing cut workpiece - Google Patents

Abstract

A holder is provided which can reduce vibration at the time of cutting processing and, in particular, vibration in directions orthogonal to the central axis of the holder. The holder comprises: a rod-shape main body which extends along a central axis L from a first end surface to a second end surface and which has a cavity that extends along the central axis L; and a cylindrical weight which is inserted into the cavity, a first fixed member which is positioned near the first end surface, and a first elastic member which is positioned between the weight and the first fixed member. In a cross section along the central axis L, the first elastic member is sandwiched from both sides by the weight and the first fixed member in the direction along the central axis L and in a direction orthogonal to the central axis L, and the width in the direction along the central axis L is greater than the width in the direction orthogonal to the central axis L.

Description

Method for manufacturing holder, cutting tool and cut work

The present disclosure relates to a cutting tool holder, a cutting tool, and a method of manufacturing a cut product used when cutting a work material such as metal.

As a cutting tool used for cutting a work material such as metal, for example, the cutting tool described in Patent Document 1 is known. The cutting tool described in Patent Document 1 has a holder and a cutting insert. The holder has a body having a cavity, a head closing the entrance of the cavity, a weight as a damping member inserted into the cavity, and an O-ring positioned between the head and the weight. Vibration of the holder can be reduced by accommodating a weight having a different natural frequency from that of the main body in the main body and vibrating the main body and the weight at different frequencies.

WO2020/049167

A non-limiting example holder in the present disclosure includes a rod-shaped body extending from a first end surface to a second end surface along a central axis and having a cavity extending along the central axis; and an internal member. The internal member includes a cylindrical weight extending from the first end face side toward the second end face side, a first fixing member positioned closer to the first end face than the weight, and the weight. and a first elastic member located between the first fixing members. In a cross section along the central axis, the first elastic member is sandwiched between the weight and the first fixing member in a direction along the central axis and a direction orthogonal to the central axis, respectively, and The width in the direction along the axis is greater than the width in the direction perpendicular to the central axis.

1 is a perspective view of a cutting tool in a non-limiting embodiment of the present disclosure; FIG. FIG. 2 is a plan view of the cutting tool shown in FIG. 1; 3 is a cross-sectional view taken along line III-III of FIG. 2; FIG. 4 is an enlarged view of the first end face side of FIG. 3; FIG. 4 is an enlarged view of the second end face side of FIG. 3; FIG. 1 is a schematic diagram illustrating one step in a method for manufacturing a machined workpiece in one non-limiting example; FIG. 1 is a schematic diagram illustrating one step in a method for manufacturing a machined workpiece in one non-limiting example; FIG. 1 is a schematic diagram illustrating one step in a method for manufacturing a machined workpiece in one non-limiting example; FIG.

Hereinafter, a method for manufacturing a holder, a cutting tool, and a cut workpiece according to embodiments, which are examples of the present disclosure, will be described in detail with reference to the drawings. However, for convenience of explanation, each drawing referred to below shows only the main members necessary for explaining the embodiment in a simplified manner. Accordingly, the holder and cutting tool may comprise optional components not shown in the referenced figures. Also, the dimensions of the members in each drawing do not faithfully represent the actual dimensions of the constituent members, the dimensional ratios of the respective members, and the like.

(Cutting tools)
FIG. 1 is a perspective view showing a cutting tool 10 according to Embodiment 1. FIG. FIG. 2 is a plan view showing the cutting tool 10. FIG. A cutting tool 10 is a tool in which a head 2 is attached to the tip side of a round bar-shaped holder 1 extending in the X-axis direction in FIG. A cutting insert (hereinafter referred to as an insert) 3 is attached to the head 2 .

The cutting tool 10 is, for example, a turning tool, and specific examples include an outer diameter machining tool, an inner diameter machining tool, a grooving tool, and a cut-off tool. The cutting tool 10 may be a milling tool whose tool side rotates. In the following description, the side of the cutting tool 10 on which the head 2 is located is called the front end side, and the side opposite to the front end side is called the rear end side.

(holder)
FIG. 3 is a cross-sectional view taken along line III--III in FIG. 4 is an enlarged view of the first end face side of FIG. 3. FIG. 5 is an enlarged view of the second end face side of FIG. 3. FIG.

As shown in FIG. 3, the holder 1 of the cutting tool 10 includes a main body 11, a first fixing member 12 as an internal member, a first elastic member 17, a weight 13, a second fixing member 16, a second elastic member 18, and a third elastic member 14 . Examples of the material of the holder 1 include steel such as stainless steel, cast iron, aluminum alloy, and the like. In particular, when steel is used among these materials, the toughness of the holder 1 can be enhanced. Each member will be described in detail below.

The main body 11 may have a round bar shape extending in the X-axis direction, and the first end face 11a on the head 2 side and the second end face 11b on the rear end side may each have a structure in which the central portion is opened. The main body 11 internally has a cavity 11c extending along the central axis (axial center) L of the holder 1 (in the X-axis direction) from the first end surface 11a toward the second end surface 11b. The cavity 11c is composed of a large-diameter portion 11d located on the first end surface 11a side and a small-diameter portion 11e that continues from the large-diameter portion 11d and extends toward the second end surface 11b.

The cavity 11c is provided by perforating a cylindrical base material made of the above material. The inner diameter of the small diameter portion 11e is smaller than the inner diameter of the large diameter portion 11d. Each of the large diameter portion 11d and the small diameter portion 11e has a cylindrical shape, and the large diameter portion 11d is thinner than the small diameter portion 11e. In FIG. 2, the large diameter portion 11d is about 2/3 the length of the holder 1, and the small diameter portion 11e is about 1/3 the length of the holder 1. The height ratio is not limited to this case.

The first fixing member 12, the first elastic member 17, the weight 13, the second fixing member 16, the second elastic member 18, and the third elastic member 14 are accommodated in the large diameter portion 11d.

The first fixing member 12 is press-fitted into the large-diameter portion 11d from the first end surface 11a of the main body 11, and functions as a lid that closes the opening formed in the first end surface 11a. Examples of materials for the first fixing member 12 include steel, cast iron, and aluminum alloys. As shown in FIG. 4, the first fixing member 12 has a substantially cylindrical shape having a first hole 12c, and is press-fitted into the large-diameter portion 11d with its axis center aligned with the central axis L. It is fixed to the surface by a pin (not shown).

The first fixing member 12 has a recess 12b, a first hole 12c, a protrusion 12d, and a tip 12e. The tip portion 12e is located on the first end face 11a side, and the dimension (diameter) of the tip portion 12e is larger than the dimension (diameter) of the large diameter portion 11d in the direction perpendicular to the central axis L (the Z-axis direction).

A serration is provided on the end face facing the head 2 of the tip portion 12e. The distal end portion 12e has a flange portion 12a that protrudes radially outward from its outer peripheral portion. The surface of the collar portion 12a facing the first end surface 11a, that is, the surface on the rear end side, contacts the first end surface 11a. This restricts the first fixing member 12 from entering the main body 11 .

The concave portion 12b is formed in a round hole shape from the central portion of the end surface of the first fixing member 12 facing the head 2 toward the rear end side. A cylindrical protrusion 24 of the head 2, which will be described later, is inserted into the recess 12b. A fourth ring-shaped elastic member 15 is interposed between the recess 12 b and the projection 24 . The fourth elastic member 15 is, for example, an O-ring or a spring, and its material includes rubber such as NBR (acrylonitrile butadiene rubber) and AU (polyester urethane rubber), synthetic resin such as epoxy resin, and the like.

The convex portion 24 is fixed to the concave portion 12b via the fourth elastic member 15. The protruding portion 12d is provided so as to protrude from the end face on the rear end side of the first fixing member 12 toward the rear end, and has a cylindrical shape with the central axis L as the axis. The first hole 12c extends from the concave portion 12b toward the second end face 11b side with its axial center aligned with the central axis L, and penetrates the projection portion 12d.

Returning to FIG. 3, the weight 13 is housed in the main body 11 in order to reduce the vibration of the holder 1 that occurs along the radial direction of the holder 1 . Weight 13 is a damping member. The weight 13 has a substantially columnar shape (more precisely, a substantially cylindrical shape) having a second hole 13c, and is attached to the first fixing member 12 in the large-diameter portion 11d with its axis aligned with the central axis L. placed adjacent to each other. The weight 13 is accommodated in the large-diameter portion 11d with a slight gap from the inner peripheral surface of the large-diameter portion 11d.

Materials for the weight 13 include high-rigidity materials such as high-speed steel, cemented carbide, and cermet. Compositions of cemented carbide include, for example, WC--Co, WC--TiC--Co and WC--TiC--TaC--Co. WC—Co is produced by adding cobalt (Co) powder to tungsten carbide (WC) and sintering it. WC--TiC--Co is obtained by adding titanium carbide (TiC) to WC--Co. WC--TiC--TaC--Co is obtained by adding tantalum carbide (TaC) to WC--TiC--Co.

In addition, cermet is a sintered composite material that combines metal with ceramic components. Specifically, as the cermet, there is a cermet having a titanium compound such as titanium carbide (TiC) or titanium nitride (TiN) as a main component.

The weight 13 has a recess 13a, a recess 13b, and a second hole 13c. The concave portion 13a is formed in a circular hole shape in the center portion of the end face of the weight 13 on the tip side. The concave portion 13b is formed in the shape of a round hole in the central portion of the end face of the weight 13 on the rear end side. The second hole 13c is provided so as to communicate the recess 13a and the recess 13b. A circulation pipe 19 through which coolant flows is inserted into the second hole 13c.

Materials for the flow pipe 19 include, for example, metal and resin. Examples of metals include copper, steel, stainless steel, and aluminum. Examples of resins include polyethylene, polypropylene, polystyrene and polyvinyl chloride. Examples of the coolant include water-insoluble oils such as oil-based, inert extreme-pressure type, and active extreme-pressure cutting oils, and water-soluble oils such as emulsion-type, soluble-type, and solution-type cutting oils.

As shown in FIG. 4, the protruding portion 12d of the first fixing member 12 is inserted inside the concave portion 13a of the weight 13 with the ring-shaped first elastic member 17 fitted thereon. The first elastic member 17 may have the same material as the fourth elastic member 15 . The first elastic member 17 is sandwiched between the protrusion 12d of the first fixing member 12 and the recess 13a of the weight 13 and is crushed, so that the tip side of the weight 13 is fixed to the first fixing member 12 by the repulsive force. be done.

4 (a cross section along the central axis L), the first elastic member 17 is arranged so that the rear end surface of the first fixing member 12 and the concave portion 13a of the weight 13 are arranged in the direction along the central axis L (the X-axis direction). It is sandwiched between the bottom of the Thus, when the first elastic member 17 is sandwiched between the first fixing member 12 and the weight 13 in the X-axis direction, the cutting load ( thrust force) can be relieved in the first elastic member 17 .

The first elastic member 17 is sandwiched between the outer peripheral surface of the protrusion 12d and the inner peripheral surface of the recess 13a in a direction perpendicular to the central axis L (the Z-axis direction) in a cross section along the central axis L. there is Thus, when the first elastic member 17 is sandwiched between the first fixing member 12 and the weight 13 in the Z-axis direction, the cutting load ( For example, the main component force and the feed component force) can be softened in the first elastic member 17 .

As described above, the weight 13 is housed in the main body 11 in order to reduce the vibration of the holder 1 that occurs along the radial direction of the holder 1 . Here, in a cross section along the central axis L as shown in FIG. It is possible to increase the effect of reducing the vibration of the weight 13 while reducing the cutting load. The fact that the width a in the X-axis direction of the first elastic member 17 is larger than the width b in the Z-axis direction can also be said to mean that the first elastic member 17 has a flat shape elongated in the X-axis direction.

When the width b in the Z-axis direction is relatively small, the amount of deformation of the first elastic member 17 in the Z-axis direction is small. Therefore, when the weight 13 vibrates in the Z-axis direction, the end of the weight 13 in contact with the first elastic member 17 tends to function as a so-called fixed end. Therefore, the effect of reducing the vibration of the weight 13 can be enhanced while avoiding damage to the weight 13 . Furthermore, rather than simply reducing the area of the first elastic member 17 in the cross section along the central axis L, the width a in the X-axis direction is large, so that the first elastic member 17 is less likely to deteriorate. It is also possible to secure the effect of relieving the cutting load due to A ratio a/b of the width a to the width b may be 1.1 or more and 3 or less.

As shown in FIG. 5, the second fixing member 16 is arranged on the rear end side of the weight 13 in the large diameter portion 11d of the cavity 11c. The second fixing member 16 fixes the weight 13 to the inner peripheral surface of the large-diameter portion 11 d via the third elastic member 14 . The second fixing member 16 has a substantially cylindrical shape having a hollow portion into which the flow pipe 19 is inserted, and is arranged in the large diameter portion 11d with its axis center aligned with the central axis L. As shown in FIG.

Examples of materials for the second fixing member 16 include metal and resin for the first fixing member 12 . Examples of metals include steel, cast iron, and aluminum alloys. Examples of resins include polyethylene, polypropylene, polystyrene and polyvinyl chloride.

The second fixing member 16 has a protrusion 16a and a groove 16b. The protruding portion 16a is provided so as to protrude toward the weight 13 from the center portion of the end surface of the second fixing member 16 facing the weight 13, and has a cylindrical shape. The groove 16b is provided in a circumferential direction on the outer peripheral surface of the second fixing member 16 facing the inner peripheral surface of the large diameter portion 11d.

The third elastic member 14 is fitted in the concave groove 16b of the second fixing member 16. The third elastic member 14 is an O-ring, for example, and may have the same material as the fourth elastic member 15 .

As shown in FIG. 5, the protrusion 16a of the second fixing member 16 is inserted inside the recess 13b with the ring-shaped second elastic member 18 fitted thereon. The second elastic member 18 may have the same material as the fourth elastic member 15 .

The second elastic member 18 is sandwiched between the protrusion 16a of the second fixing member 16 and the recess 13b of the weight 13, and the rear end side of the weight 13 is fixed to the second fixing member 16 by the repulsive force caused by being crushed. . The second fixing member 16 is fixed to the large-diameter portion 11d by the repulsive force caused by the third elastic member 14 contacting and being crushed by the inner peripheral surface of the large-diameter portion 11d of the cavity 11c. That is, both ends of the weight 13 are held by a first fixing member 12 fixed to the large diameter portion 11d and a second fixing member 16 fixed to the large diameter portion 11d via a third elastic member 14. Thus, it is integrated with the first fixing member 12 and the second fixing member 16 and fixed to the large diameter portion 11d.

The second elastic member 18 is sandwiched between the bottom surface of the concave portion 13b of the weight 13 and the tip side surface of the second fixing member 16 in the X-axis direction in the cross section (cross section along the central axis L) in FIG. is Thus, when the second elastic member 18 is sandwiched between the second fixing member 16 and the weight 13 in the X-axis direction, the cutting load ( thrust force) can be relieved in the second elastic member 18 .

The second elastic member 18 is sandwiched between the inner peripheral surface of the recess 13b and the outer peripheral surface of the protrusion 16a in the Z-axis direction. Thus, when the second elastic member 18 is sandwiched between the second fixing member 16 and the weight 13 in the Z-axis direction, the cutting load ( For example, the main component force and the feeding component force) can be softened in the second elastic member 18 .

As described above, the weight 13 is housed in the main body 11 in order to reduce the vibration of the holder 1 that occurs along the radial direction of the holder 1 . Here, in a cross section along the central axis L as shown in FIG. It is possible to increase the effect of reducing the vibration of the weight 13 while reducing the cutting load. The fact that the width c in the X-axis direction of the second elastic member 18 is larger than the width d in the Z-axis direction can also be said to mean that the second elastic member 18 has a flat shape elongated in the X-axis direction.

When the width b in the Z-axis direction is relatively small, the amount of deformation of the second elastic member 18 in the Z-axis direction is small. Therefore, when the weight 13 vibrates in the Z-axis direction, the end of the weight 13 in contact with the second elastic member 18 tends to function as a so-called fixed end. Therefore, the effect of reducing the vibration of the weight 13 can be enhanced while avoiding damage to the weight 13 . Furthermore, rather than simply reducing the area of the second elastic member 18 in the cross section along the central axis L, the width a in the X-axis direction is large, so that the second elastic member 18 is less likely to deteriorate. It is also possible to secure the effect of relieving the cutting load due to The ratio c/d of the width c to the width d may be 1.1 or more and 3 or less.

As shown in FIG. 3, the diameter of the opening of the second end surface 11b of the main body 11 substantially matches the diameter of the small diameter portion 11e. Coolant is injected into the small diameter portion 11e through the opening. The opening is closed by plug 20 . As shown in FIG. 4, the distal end of the flow pipe 19 enters the first hole 12c, and the first hole 12c and the second hole 13c are connected. The injected coolant passes through the flow pipe 19 and is ejected from an ejection portion 23 of the head 2, which will be described later, during machining.

(head)
As shown in FIGS. 1 to 3, the head 2 includes a mounting portion 21 having a substantially cylindrical shape, and a mounting portion 22 having a polyhedral shape and protruding from the front end surface of the mounting portion 21 in the X-axis direction. have The attachment portion 21 is attached to the distal end portion of the holder 1 with its axis aligned with the central axis L of the holder 1 . Serrations are provided on the end surface of the mounting portion 21 on the holder 1 side. The serrations provided on the mounting portion 21 are fitted to the serrations formed on the end face of the first fixing member 12 on the distal end side. With these serrations fitted, the head 2 is attached to the holder 1 using screws (not shown) or the like.

A jetting portion 23 having an opening from which coolant is jetted is provided on the tip surface of the mounting portion 21 . A convex portion 24 is provided in a central portion of the end face on the rear end side of the mounting portion 21 so as to protrude toward the first fixing member 12 . The tip of the convex portion 24 and the ejection portion 23 are connected (not shown). As described above, the internal space of the convex portion 24 communicates with the internal space of the communication pipe 19 via the first hole 12c of the first fixing member 12 . The coolant injected into the small-diameter portion 11e flows through the convex portion 24 through the flow pipe 19, and is ejected from the ejection portion 23 toward the work material during machining.

A pocket 22a is provided at one end in the Y-axis direction when the mounting portion 22 is viewed from the Z-axis direction. The pocket 22a has a seat surface (not shown) on which the bottom surface of the insert 3 is placed, and a constraining side surface against which the two side surfaces of the insert 3 abut and are constrained. The shape of the insert 3 is not limited to any particular configuration. For example, the shape of the insert 3 may be a rod-shaped, polygonal plate-shaped or polygonal prism-shaped configuration. In this embodiment, the insert 3 is in the form of a rhombic plate, as shown in FIG.

A corner of the rhombic shape of the insert 3 is cut out to form a cutting edge 3a. Materials for the insert 3 include cemented carbide, cermet, and the like. The cemented carbide and cermet may have the same composition as the cemented carbide and cermet of the weight 13 . A through hole is provided in the center of the insert 3, and the insert 3 is fixed to the pocket 22a by placing the rhombic bottom surface on the seat surface and inserting a screw through the through hole and screwing it to the seat surface. there is

(Manufacturing method of cut product)
Next, a method for manufacturing a machined product according to the embodiment will be described with reference to the drawings. FIG. 6 is a schematic diagram illustrating one step in a method of manufacturing a machined workpiece 103 in one non-limiting example. FIG. 7 is a schematic diagram illustrating one step in a method of manufacturing a machined workpiece 103 in one non-limiting example. FIG. 8 is a schematic diagram illustrating one step in a method of manufacturing a machined workpiece 103 in one non-limiting example.

The workpiece 103 is produced by cutting the workpiece 101 . In the embodiment, outer diameter machining is exemplified as cutting. The manufacturing method of the cut workpiece 103 in the embodiment includes the following steps. i.e.
(1) a step of rotating the work material 101;
(2) contacting the rotating work material 101 with the cutting tool 10 represented by the above embodiment;
(3) separating the cutting tool 10 from the work material 101;
including.

More specifically, first, as shown in FIG. 6, the work material 101 is rotated around the axis D in the D1 direction. Also, by moving the cutting tool 10 in the D2 direction, the cutting tool 10 is brought relatively close to the work material 101 . Next, as shown in FIG. 7, the cutting edge 3a of the cutting tool 10 is brought into contact with the work material 101 to cut the work material 101. Next, as shown in FIG.

At this time, outer diameter machining can be performed by cutting the work material 101 while moving the cutting tool 10 in the D3 direction. Then, as shown in FIG. 6, by moving the cutting tool 10 in the D4 direction, the cutting tool 10 is moved away from the work material 101 relatively.

In FIG. 6, the cutting tool 10 is approached while the shaft D is fixed and the work material 101 is rotated. In FIG. 7, the work material 101 is cut by bringing the cutting edge 3a of the insert 3 into contact with the work material 101 that is rotating. Also, in FIG. 8, the cutting tool 10 is kept away while the work material 101 is being rotated.

As described above, in the present embodiment, the cross sections of the first elastic member 17 and the second elastic member 18 are elongated in the direction along the central axis L and have a flat shape. 11 vibration is reduced.

In the cutting process in the manufacturing method of the embodiment, the cutting tool 10 is brought into contact with the cut material 101 by moving the cutting tool 10 . Further, the cutting tool 10 is separated from the work piece 101 by moving the cutting tool 10 . However, the manufacturing method of the embodiment is not limited to this case.

For example, in step (1), the work material 101 may be brought closer to the cutting tool 10 . In step (3), the work material 101 may be kept away from the cutting tool 10 . When cutting is to be continued, the cutting tool 10 is held in a rotating state, and the step of bringing the insert 3 into contact with different portions of the work material 101 may be repeated.

Representative examples of the material of the work material 101 include carbon steel, alloy steel, stainless steel, cast iron and non-ferrous metals.

The invention according to the present disclosure has been described above based on the drawings and embodiments. However, the invention according to the present disclosure is not limited to each embodiment described above. That is, the invention according to the present disclosure can be variously modified within the scope shown in the present disclosure, and the embodiments obtained by appropriately combining the technical means disclosed in different embodiments can also be applied to the invention according to the present disclosure. Included in the technical scope.

In other words, it should be noted that a person skilled in the art can easily make various modifications or modifications based on the present disclosure. Also, note that these variations or modifications are included within the scope of this disclosure. For example, in the above-described embodiment, the case where the holder 1 of the cutting tool 10 is in the shape of a round bar has been described, but it may be in the shape of a square bar. In addition, although both the first elastic member 17 and the second elastic member 18 have flat cross-sections elongated in the direction along the central axis L, either one of them may have a flat shape. good.

Reference Signs List 1 holder 11 main body 11a first end face 11b second end face 11c cavity 12 first fixing member 12a flange 12d projection 13 weights 13a, 13b recess 14 third elastic member 15 fourth elastic member 16 second fixing member 17 first elastic Member 18 Second elastic member 16a Projection 16b Groove 2 Head 24 Projection 3 Insert 3a Cutting edge 10 Cutting tool

Claims (9)

a bar-shaped body extending from a first end face to a second end face along a central axis and having a cavity extending along the central axis;
an internal member inserted into the cavity;
The internal member is
a cylindrical weight extending from the first end face side toward the second end face side;
a first fixing member positioned closer to the first end face than the weight;
a first elastic member located between the weight and the first fixing member;
In a cross section along the central axis, the first elastic member has
sandwiched between the weight and the first fixing member in a direction along the central axis and a direction orthogonal to the central axis, and
A holder, wherein a width in a direction along the central axis is larger than a width in a direction orthogonal to the central axis. 2. The method according to claim 1, wherein in a cross section along the central axis, the first elastic member contacts the weight and the first fixing member in a direction along the central axis and a direction perpendicular to the central axis, respectively. holder as described. The first fixing member has a tip located on the first end face side,
3. The holder according to claim 1 or 2, wherein the dimension of the tip is larger than the dimension of the cavity in a direction orthogonal to the central axis. The holder according to claim 3, wherein a portion of the tip portion facing the peripheral portion of the first end surface abuts on the first end surface. The internal member is
a second fixing member located closer to the second end face than the weight;
a second elastic member positioned between the weight and the second fixing member;
In a cross section along the central axis, the second elastic member has
sandwiched between the weight and the second fixing member in a direction along the central axis and a direction orthogonal to the central axis, and
3. The holder according to claim 1, wherein the width in the direction along the central axis is larger than the width in the direction perpendicular to the central axis. 6. The method according to claim 5, wherein in a cross section along the central axis, the second elastic member contacts the weight and the second fixing member in a direction along the central axis and a direction perpendicular to the central axis, respectively. holder as described. further comprising a third elastic member positioned between the main body and the second fixing member and in contact with the main body and the second fixing member in a direction orthogonal to the central axis;
6. The holder of claim 5, wherein said first securing member is press fit into said cavity. a holder according to claim 1 or 2;
a cutting insert located on the first end face side of the holder. rotating the work material;
A step of bringing the cutting tool according to claim 8 into contact with the rotating work material;
and separating the cutting tool from the work material.

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