Abstract: A display device manufacturing method is provided including a display module in which an active area and a non-active area surrounding the active area are defined. A first hole is perforated having a first diameter on the active area. A second hole is formed having a second diameter by irradiating a laser area at least partially surrounding the first hole with a laser. The second diameter is larger than the first diameter.

Abstract: A tool quick-stop device for a lathe has a base, bottom plate, front side plate, rear side plate, right side plate, left side plate, top fixed plate, tool bar, cam lever, buffer spring, cylindrical guide rail, adjusting nut, first locking nut, double end stud, second locking nut, pressure spring, pressing plate, hold-down bolt and pin shaft. The cam lever supports the tool bar before tool falling. When tool falling is required, the cam lever is rotated through external force. When the cam lever rotates over a certain position, the tool bar instantaneously loses supporting force. Under strong pressure of the pressure spring, the tool bar falls the tool with great acceleration and is separated from the cutting region in a short period of time and the cutting root is frozen.

Abstract: To provide a method of processing a tempered glass in a simple and appropriate manner while a degree of freedom of processing is secured. Vibration of the processing device is controlled in a feedback fashion such that a vibration amplitude and a vibration frequency of the processing device approach to a target vibration amplitude and a target vibration frequency not to keep them in a range where a value of worsening the quality is generated. Further, a specified sample cycle of 0.3 msec or less in the feedback control is employed.

Abstract: A blade including a body has a front surface and a curved back cutting surface. The front surface has a mount angle relative to a material surface of a material facing the back cutting surface. The back cutting surface has a substrate clearance angle relative to the material surface. In response to at least one of the blade and the material surface being brought into cutting contact and moved relative to each other, a resulting portion of the material surface has a distressed appearance.

Abstract: A method and apparatus for processing workpieces to form parts. Tools associated with a multi-spindle machine may be positioned with respect to a plurality of workpieces on a fixture comprising a plurality of platforms and an adjustment system. Each platform may be individually moveable with respect to others in the plurality of platforms about a number of axes. The plurality of platforms may be configured to hold the plurality of workpieces in which each platform may be configured to hold a workpiece in the plurality of workpieces during operations performed by the multi-spindle machine. The adjustment system may be configured to move each of the plurality of platforms about the number of axes independently from the others in the plurality of platforms. The operations may be performed on the plurality of workpieces using the multi-spindle machine and the fixture to form a plurality of parts.

Abstract: A free form cutting machine is disclosed. The free form cutting machine includes a table, a spindle; and a cutting arrangement attached to the spindle. The cutting arrangement having at least a cutting tool used to cutting selected portions from a workpiece on the table. The free form cutting machine causes the cutting tool to apply a continuous shaping force to the surface of the workpiece until a first surface shape of the workpiece conforms with a predefined finished spline surface shape.

Abstract: A method of forming a recess in a work, a work in which the recess is to be formed is a material that can be cut. A cutting tool for forming the recess is held by a moving apparatus at a prescribed angle relative to the work. The cutting tool is moved in a carving direction for carving the work at the prescribed angle, and a thin cutting fin is vertically formed. Then, the cutting tool is moved in the horizontal direction, and the cutting fin is cut and separated from the work. The fin-forming step and the cutting step are repeatedly performed in sequence, whereby a recess having a prescribed depth d and area is formed in the work.

Abstract: An external weld bead is removed and processed from a welded pipe traveling in a downstream direction. The weld bead is separated from the pipe, guided through a guide passage having an inlet and an outlet, and cut into pieces at the guide passage outlet in a location above the pipe.

Abstract: A tool cutting apparatus includes a chuck table for holding a workpiece, and rotatable cutting means having a cutting tip for cutting the front side of the workpiece. Pure water and an additive are mixed to prepare a cutting fluid, and a cutting fluid nozzle supplies the cutting fluid to the cutting tip and the workpiece held on the chuck table.

Abstract: A non-rotary shaping method (700, 800, 900) and shaping center (600) for forming a part using a non-rotating cutting tool (400) for removing material from a non-rotating workpiece within a three-dimensional work envelope that obsoletes the use of mills for profiling operations. Without the need to rotate to produce sufficient surface footage to remove material, the cutting tool (400) applies constant cutting force to the workpiece along a one-, two-, or three-dimensional cutting path at a sufficiently high feed rate to remove material by means of controlled fracturing instead of plastic deformation. Also, without the need to rotate, neither the cutting tool nor the part are constrained in shape by axial symmetrical. Therefore, parts without any restriction in shape can be produced with finer surface finishes and higher material removal rates than by milling.

Abstract: An end face of a sheet member is cut while rotating a cutting member having a rotation axis extending along a vertical direction of the end face of the sheet member and a cutting blade projecting to a side of the end face of the sheet member around the rotation axis. The cutting member is moved relatively to the sheet member along a longitudinal direction of the end face to be cut. The part separated from a virtual line parallel to the sheet face and passing the rotation center in a cutting region formed by the rotating cutting blade is made to contact the end face of the sheet member.

Abstract: The invention concerns a blade holder for smoothing and planing off a substrate comprising a handle, a receiving means including a receiving space for a blade, wherein the blade has a larger blade side surface and a narrow side which is at the rear in a cutting direction and which has a cutting edge, and a positioning aid for positioning the blade holder relative to the substrate, wherein the positioning aid includes a spacer device, by means of which the blade can be arranged in a spaced position in the receiving means in such a way that it can be positioned in spaced relationship with the substrate with its cutting edge for processing the substrate. The invention further concerns a method and a blade for the blade holder.

Abstract: An apparatus (100) and method (200) of contact machining having applications in profiling operations utilizes at least one static cutting tool (101) and turret (102) driven by rotary motion (103) about a support mechanism (109) for providing sufficient force to achieve deformation by controlled fracturing (523). This allows the separation of material from a workpiece (105) without imposing axial symmetry upon either the cutting tool (101) or the workpiece (105). The apparatus and method mitigates and/or eliminates the adverse effects of plastic deformation (504) while machining a wider range of shapes and materials with greater productivity and precision than existing methods of machining.

Abstract: A non-rotary shaping method (700, 800, 900) and shaping center (600) for forming a part using a non-rotating cutting tool (400) for removing material from a non-rotating workpiece within a three-dimensional work envelope that obsoletes the use of mills for profiling operations. Without the need to rotate to produce sufficient surface footage to remove material, the cutting tool (400) applies constant cutting force to the workpiece along a one-, two-, or three-dimensional cutting path. Also, without the need to rotate, neither the cutting tool nor the part are constrained in shape by axial symmetrical. Therefore, parts without any restriction in shape can be produced with finer surface finishes and higher material removal rates than by milling.

Abstract: A post treatment process of a seamed belt for providing a smooth surface and substantially eliminating protrusions by using a planing blade, and a seamed belt that has undergone the post treatment.

Abstract: By cutting-machining a side face of a scroll wrap with a non-rotational tool, swells in the perimeter direction have a smaller size. Thus, compressed gas is prevented from leaking between relatively slidable side faces of the respective wraps of the stationary scroll and the slewing scroll. This configuration provides a scroll compressor that has a higher accuracy and thus high compression efficiency and low noise are realized.

Abstract: A method of manufacturing a grooved polishing pad wherein a large number of grooves, extending parallel to each other, are fabricated at specific intervals on at least one of a front surface and a back surface of a polishing pad substrate through a groove cutting process on the polishing pad substrate which is made from a synthetic resin material, the method comprising the steps of: cutting, by using a multi-edged tool having a plurality of pad groove machining cutting parts, arrayed at equal spacing p with the spacing p being an integer multiple no less than 2 of a desired spacing d of the grooves, a plurality of the grooves; and repeating the cutting of the plurality of grooves through shifting the multi-edged tool in a direction in which the pad groove machining cutting parts are arrayed, in order to fabricate the large number of grooves, extending parallel to each other, with the desired spacing d.

Abstract: A material cutting machine has a tool mount support mounted for reciprocal movement and a tool mount supported by the tool mount support. A driver, such as a pneumatic cylinder, selectively advances and retracts the tool mount support. A control system is operatively coupled to the driver for setting the advancement force of the tool mount support when a tool supported by said tool mount contacts a workpiece, such as the edge or surface of a moving strip. In this way, the depth of cut of the tool is controlled by tool advancement force rather than by accurate positioning of the tool. In one embodiment, the tool mount support may have a head and a base and a resilient member resiliently coupling the head to the base to provide a damped resilience. With this embodiment, a transient spike in the reaction force which may result, for example, from a hard spot in the material, causes the tool to momentarily deflect.

Abstract: A microscopic geometry cutting device includes: a controller that outputs a timer count start command in starting a driving program which controls a drive of an X-axis or a Y-axis moving mechanism; an arrival time calculator that calculates an arrival time from when the timer count start command is output till when the cutter arrives at a machining start position in accordance with relative moving speed information of the moving mechanisms and machining start position information of a workpiece W; an elapsed time determiner that determines whether an elapsed time from when the timer count start command is output is coincident with the arrival time and outputs a trigger signal when the elapsed time is coincident with the arrival time; and a reciprocating stage driver that drives the reciprocating stage in a manner that the cutter advances and retracts in a predetermined cutting depth in response to the trigger signal.

Abstract: A method of creating a triangulated surfaces for generating machine readable instructions for customization is provided. The method comprises selecting text or symbols. The text or symbols are spaced. The text or symbols are mapped between first and second curves. Triangulated surfaces are generated from the mapped text or symbols. The triangulated surfaces are converted to machine readable instructions.

Abstract: In the machine tool according to the present invention, a cutting tool 25 is configured to be optionally turned to take each reverse orientation, based on a C axis as the center of rotation about the Z axis, which is vertical to the X-Y plane parallel to a top face of a work 13. First, the orientation of the cutting tool 25 is set to correspond to machining in an advancing stroke for the work 13, so as to perform the machining for the work while moving it in an advancing direction. Then, the orientation of the cutting tool is reversed, so as to perform the machining for the work while moving it in a retracting direction.

Abstract: A process of machining a scroll member of a scroll compressor by using a non-rotary cutting tool. The non-rotary cutting tool is moved relative to a workpiece in a predetermined direction for cutting the workpiece, with its rake face being held substantially perpendicular to the predetermined direction. The cutting tool includes (a) a generally cylindrical shank portion, and (b) a generally semi-cylindrical body portion which has an outer circumferential surface constituted by the rake face and a semi-cylindrical surface. The semi-cylindrical body portion has a cutting edge which is defined by an edge of the rake face and which is covered with a diamond coating. The rake face has a planar surface and a constant width throughout the cutting edge.

Abstract: The present invention mainly aims to provide cutting method and cutting apparatus for manufacturing a guide rail of a rolling guide device by efficiently cut-working a long scale hardened steel. In order to achieve such object, there is provided a cutting method of linearly cutting a work surface (3) of the long scale hardened steel (2) along the longitudinal direction thereof. In this process, it is desired to arrange a plurality of CBN tools (7) along the longitudinal direction of the long scale hardened steel (2) to thereby sequentially cut the work surface (3). Furthermore, a cutting apparatus of the present invention comprises a fixing device (4) for fixing the long scale hardened steel (2), a tool rest (5) which is guided by a guide device (6) disposed along the longitudinal direction of the fixing device (4) and the CBN tool (7) cut-working the work surface (3) of the long scale hardened steel (2) held by the tool rest (5).

Abstract: A device 1 and a method for trimming samples 38 are disclosed. The device 1 encompasses a knife holder 9 and a sample holder 7, the knife holder 9 carrying at least one trimming knife 36. A first motor 60 and a second motor 61 are provided, which move the knife holder 9 in an X-Y plane. Also provided is a control unit 15 that controls the motion of the knife holder 9. The first and the second motor 60, 61 are each equipped with a measurement means 62, 63 that measures the position of the knife holder 9 in the X direction (X) and Y direction (Y).

Abstract: The present invention mainly aims to provide cutting method and cutting apparatus for manufacturing a guide rail of a rolling guide device by efficiently cut-working a long scale hardened steel. In order to achieve such object, there is provided a cutting method of linearly cutting a work surface (3) of the long scale hardened steel (2) along the longitudinal direction thereof. In this process, it is desired to arrange a plurality of CBN tools (7) along the longitudinal direction of the long scale hardened steel (2) to thereby sequentially cut the work surface (3). Furthermore, a cutting apparatus of the present invention comprises a fixing device (4) for fixing the long scale hardened steel (2), a tool rest (5) which is guided by a guide device (6) disposed along the longitudinal direction of the fixing device (4) and the CBN tool (7) cut-working the work surface (3) of the long scale hardened steel (2) held by the tool rest (5).

Abstract: An apparatus and method for forming a keyway in a workpiece is provided. The apparatus includes a shank and cutter, the shank and cutter immovably associated with respect to each other during the keyway forming operation. The apparatus is engageable with a computer numeric controlled machine. The method of forming a keyway in a workpiece includes a reciprocating, chiseling motion for removing layers of material from the workpiece.

Abstract: A device for deburring the inside of a longitudinally seam-welded pipe includes a retention arm secured outside the pipe in the area of the pipe that is not yet closed and having an end zone which is located behind the welding spot. Arranged on the retention arm is a frame part which is tiltable in longitudinal direction of the pipe about a tilt axis and provided with a scraping tool. The tilt axis of the frame part is hereby located, as viewed in advancing direction, behind the scraping point at the end of the frame part. An adjustment mechanism is provided on the forward end of the frame part for adjusting the tilt angle.

Abstract: A non-rotary cutting tool which is to be moved relative to a workpiece in a predetermined direction for cutting the workpiece, with its rake face being held substantially perpendicular to the predetermined direction. The cutting tool includes (a) a generally cylindrical shank portion, and (b) a generally semi-cylindrical body portion which has an outer circumferential surface constituted by the rake face and a semi-cylindrical surface. The semi-cylindrical body portion has a cutting edge which is defined by an edge of the rake face and which is covered with a diamond coating. Also disclosed is a process of machining a scroll member of a scroll compressor by using this non-rotary cutting tool.

Abstract: An elliptical vibratory cutting apparatus includes a control mechanism which applies a sinusoidal voltage having a predetermined phase difference to piezoelectric elements. Flexure vibrations are accordingly generated in X and Y directions. The vibrations in the X direction cause interference with the vibrations in the Y direction and vice versa. An amount of interference, caused by vibrations in one direction, with vibrations in another direction, is correctively eliminated by the control mechanism (interference eliminating unit. A workpiece is thus cut by means of a cutting tool through elliptical vibrations with high precision.

Abstract: A cutter holder assembly for holding a cutting tool supported at a tool carriage moving in at least an X-Y plane and provided with a cutter for engraving an item to be engraved includes a mounting base capable of being fitted to the tool carriage, a holder base supported at the mounting base in such a manner as to be freely moveable along a Z-axis provided in direction of a prescribed straight line, and a cutter holder having a cutting tool support supporting the cutting tool and being fixed to the holder base. Rotation of the cutter holder about the Z-axis with respect to the mounting base is restrained and an angle of inclination &thgr; constituted by an angle formed when a longitudinal axis of the cutter and the Z-axis intersect can be held at a prescribed angle. It is therefore possible to provide a cutter holder assembly for an engraver capable of implementing engraving technology capable of a variety of types of engraving of a wide variation without limitation at a part to be engraved.

Abstract: A burr located at an edge of a steel piece is cut by disposing a cutter such that the flank of the cutter is substantially in parallel with the surface of the steel piece and the angle between the cutting edge of the cutter and the edge of the steel piece which the burr intersects is at least 45°. The cutter is relatively moved toward the outside of the steel piece along the lengthwise direction of the burr, or the cutter is disposed with the flank of the cutter substantially in parallel with the surface of the steel piece and the angle between the cutting edge of the cutter and the edge of the steel piece is at least 90°. The burr located at the edge of the steel piece is cut by relatively moving the cutter perpendicularly to the lengthwise direction of the burr.

Abstract: The present invention mainly aims to provide cutting method and cutting apparatus for manufacturing a guide rail of a rolling guide device by efficiently cut-working a long scale hardened steel. In order to achieve such object, there is provided a cutting method of linearly cutting a work surface (3) of the long scale hardened steel (2) along the longitudinal direction thereof. In this process, it is desired to arrange a plurality of CBN tools (7) along the longitudinal direction of the long scale hardened steel (2) to thereby sequentially cut the work surface (3). Furthermore, a cutting apparatus of the present invention comprises a fixing device (4) for fixing the long scale hardened steel (2), a tool rest (5) which is guided by a guide device (6) disposed along the longitudinal direction of the fixing device (4) and the CBN tool (7) cut-working the work surface (3) of the long scale hardened steel (2) held by the tool rest (5).

Abstract: The invention relates to a process and a device for producing a contour of a planiform piece, intended, in particular, for the internal trim of motor vehicles, in which said piece (1) is cut to define at least an apex (2) of said contour (3), having a given profile P, and a side (4), or so-called first side, of said contour (3) extending from said apex (2). According to the invention, there are carried out sequentially: on one hand, cutting of said piece (1) to produce simultaneously at least said apex (2), according to said profile P, and to cut said first side (4) over a portion, referred to as a fraction F, of its length extending from said apex (2); on the other hand, at least another operation of cutting said piece (1) to produce said first side (4), including at least a portion at least of said fraction F.

Abstract: A method for forming a key-engaging part of an axial-hole member and a key-engaging part structure which realize an efficient formation of a key-engaging part in an axial-hole member are provided. A key-engaging through hole is formed in a key-engaging part of an axial-hole member while both end portions of the axial-hole member leave intact such that the key-engaging through hole is bored through the axial-hole member in the radial direction. The key-engaging part is formed using this through hole.

Abstract: An elliptical vibratory cutting apparatus includes a control mechanism which applies a sinusoidal voltage having a predetermined phase difference to piezoelectric elements. Flexure vibrations are accordingly generated in X and Y directions. An amount of interference, caused by vibrations in one direction, with vibrations in another direction, is correctively eliminated by the control mechanism (interference eliminating unit 22). A workpiece is thus cut by means of a cutting tool through elliptical vibrations.

Abstract: The invention relates to the generation of periodic profiles on at least approximately rotationally symmetrical blanks, such as, for example, the generation of shaft-hub connection profiles such as circular wedge profiles, splined shaft profiles, etc., on shaft or hub blanks. To this end, the use of generating skiving is proposed, which permits the production of any desired periodic profiles on rotationally symmetrical blanks and is far superior to rival processes with regard to the productive machining time.

Abstract: In a burr removing method and apparatus of the present invention, a burr located at an edge of a steel piece is cut with a cutter by disposing the cutter such that the flank of the cutter is substantially in parallel with the surface of the steel piece on which the burr exists and the angle between the cutting edge of the cutter and the edge of the steel piece which the burr intersects is at least 45° and relatively moving the cutter toward the outside of the steel piece along the lengthwise direction of the burr; or by disposing the cutter such that the flank of the cutter is substantially in parallel with the surface of the steel piece on which the burr exists and the angle between the cutting edge of the cutter and the edge of the steel piece which the burr intersects is at least 90° and cutting the burr located at the edge of the steel piece by relatively moving the cutter perpendicularly to the lengthwise direction of the burr.

Abstract: A device for forming a cutting blade for prints is disclosed. The device of this invention forms cutting blades by appropriately bending and cutting a metal strip into desired blades through integrated work regardless of a difference in the size of metal strips. The device is also provided with changeable jigs, thus being capable of forming bridge notches having different intervals, widths and configurations. The device has one vertically movable bending pin and one swing cutter. The bending pin is capable of quickly bending a metal strip into a desired configuration, while the swing cutter finely and precisely cuts the metal strip into cutting blades. The device also quickly produces high precision cutting blades, thus improving productivity and reducing the cost of the cutting blades.

Abstract: According to this invention, introduction of dynamic, closed-loop force and position control over press rolls of a planer or infeed table provides a dramatic increase in capability, performance, and reliability, as compared to the prior art.

Abstract: In a burr removing method and apparatus of the present invention, a burr located at an edge of a steel piece is cut with a cutter by disposing the cutter such that the flank of the cutter is substantially in parallel with the surface of the steel piece on which the burr exists and the angle between the cutting edge of the cutter and the edge of the steel piece which the burr intersects is at least 45° and relatively moving the cutter toward the outside of the steel piece along the lengthwise direction of the burr; or by disposing the cutter such that the flank of the cutter is substantially in parallel with the surface of the steel piece on which the burr exists and the angle between the cutting edge of the cutter and the edge of the steel piece which the burr intersects is at least 90° and cutting the burr located at the edge of the steel piece by relatively moving the cutter perpendicularly to the lengthwise direction of the burr.

Abstract: Apparatuses and methods are implemented for machining a longitudinally extending slot in a bore of a component. The component is gripped in a gripping device of a workholding device. A cutting operation is performed in order to cut the slot in the bore by a cutting tool. The cutting operation forms burred slot edges. The edges are further machined by inserting a deburring device into the bore. Relative angular reciprocation for a limited angle is imparted between the deburring device and the component.

Abstract: A deburrung method, in which a laser (3) is directed towards the edge of a workpiece (1) so that the position of a first surface (5) and a second surface (6) joining the first surface at an angle, can be deternined, after which extrapolation of a cutting curve (8) between the first surface (5) and the second surface (6) is performed and in that the burr (2) is removed along the cutting curve (8).

Abstract: A method for cutting openings in a sheet of thermoformed containers. The sheet of containers is indexed into a cutting assembly. The cutting assembly includes a shear plate having a plurality of openings formed therethrough, and having an upper surface which defines a cutting plane. A locating means including a plurality of anvils is raised so that the anvils enter the containers and raise the sheet toward the shear plate. The end portions of the containers are located within the openings of the shear plate, and a portion of the containers is positioned in the cutting plane. The cutting assembly includes a blade mounted on piston/cylinder assembly for sliding movement along the upper surface of the shear plate. The cylinder is actuated to move the blade along the cutting plane. The blade cuts off the portion of the containers and creates an opening in the containers.

Abstract: A method and device for machining an angularly disposed array of parallel longitudinally extending slots in a bore of a component, the method comprising the steps of: gripping said component (1) in a gripping means of a workholding device (2) mounted to a workholding spindle (3) indexable about a first axis; cutting said array of slots in said bore by a series of progressively deeper cutting strokes of a cutting tool (5), said tool mounted to a cutting spindle (7) rotatable about a second axis (8) substantially at right angles to and offset from said first axis; and the cutting of each slot followed by indexation of said workholding spindle (3); and during the cutting of at least one of said slots, relative movement between the component (1) and second axis (8) takes place due to movement of the component (1) along the first axis or movement of the second axis in a direction substantially parallel to said first axis or both.

Abstract: This invention relates to a method for manufacturing a plurality of longitudinally extending slots in the bore of a component (1). One example of such a component is the sleeve element of an automotive power steering rotary valve. More particularly the invention is directed towards a method of minimising burring of the slot edges of the sleeve component. The method comprises the steps of gripping the component (1) in a gripping mechanism (2) of a workholding device, performing a first cutting operation (5) in which the slot is cut in the bore by a series of progressively deeper cutting stroke of a cutting tool (5), further machining (30) the bore of the component, the machining of the bore being carried out while the component remains gripped in the gripping mechanism, characterized in that while the component remains gripped in the gripping mechanism the slot undergoes a second cutting operation (5) similar to the first operation.

Abstract: A method for forming at least a portion of the edge 12, 14 of an airfoil 10 using a cutting tool 164 is disclosed. Various details of this method are developed which enable incremental removal of material by repetitively moving the tool with respect to the edge while positioning the tool with respect to a spanwisely extending airfoil R.sub.5, on the airfoil.

Abstract: A planing device for planing a first, movable surface of a machine is set forth. The machine includes a second surface from which the first, movable surface can be retracted. The planing device includes a base and a planing assembly. The base is slidably connected to the second surface and partially seated in an interspace formed between the first and second surfaces. The planing assembly includes a stationary planing tool and is connected to the base.

Abstract: A tool T is mounted to the tip of the rotatable main shaft S, and at least the rotation angle of the main shaft S is controlled so that the edge of the tool T is always maintained at the right angle against the direction of the tool movement on the machining program locus, when a work W is machined with the edge T.sub.A of the tool T in the state that the edge T.sub.A of the tool T is offset from the rotation center S.sub.0 of the main shaft S.

Abstract: A method of forming grooves with cutting edges in the sides of the teeth of a shaving cutter comprises, in order:a first machining step with the removal of shavings, in the course of which a plurality of grooves is formed, each groove having two side walls substantially perpendicular to a plane tangential to the respective side of the tooth, anda second machining step with the removal of shavings, in the course of which the side walls of each groove are machined to produce a cutting edge with an acute cutting angle.

Abstract: A machine tool having a machining member such as a grinding wheel, a milling cutter, shaping cutter or also includes a slide on which a straight edge bar is mounted. The straight edge bar is engaged by the machining member to machine a surface on the bar held on the slide. The slide is moved at the feed rate used for machining with the particular machining member used, and then the bar is rotated about its longitudinal axis, that is, the axis parallel to the movement of the slide. The amount of error from a straight line that has been formed is sensed by sensors positioned in the same plane as the contact line of the grinding wheel. The actual error of the slide is thus determined, and portions of the surface of the bar can be gradually scraped or refined by other means until the sensors indicate that the surface has become a precise straight edge. The straight edge surface can then be used as a reference for checking workpieces or for automatic error compensation. Surfaces at 90.degree.