Abstract: Systems and methods for a high speed drill cutting burr are described. The high speed drill may comprise a main body having a first section and a second section, the first section comprising a first housing configured to be operably connectable to a first cutting tip and the second section comprising a second housing configured to be operably connectable to a second cutting tip, and an electrical motor disposed inside the main body, the electrical motor may be configured to be in electrical communication with a power source. In some embodiments, a main body may be repositioned by rotating the main body 180° to switch between use of a first cutting tip and a second cutting tip. Mechanisms for limiting axial movement of a burr shank as well as transferring torque are described.

Abstract: The present invention is directed to systems, methods, tools and surgical procedures that provide for improved, faster and/or more efficient methods for cleaning bone of soft tissue in preparation for use in bone grafting and surgery, including specific applications particularly useful in fusion procedures and/or other surgeries of the lumbar, cervical, and/or thoracic spine and/or other anatomical locations, desirably allowing for faster and complete healing.

Abstract: A machine tool is provided which comprises a machine base (10), a first support (20,100) mounted on a first rotational machine axis on the base, and a second support (22,102) mounted on a second rotational machine axis on the base. The second rotational axis is parallel to and spaced laterally from the first rotational axis and carries a mount (38,112) moveable relative to the second support along a first linear machine axis orthogonal to the second rotational axis. A control arrangement is operable to control the orientation of the first support on the first rotational axis, and the orientation of the mount relative to the second rotational axis and its location along the linear axis, so as to govern the position and orientation of the first support and the mount relative to each other. Existing machine tools often use long linear guide rails and stacked orthogonal axes which introduce alignment and offset errors.

Abstract: A machine tool is provided which comprises a machine base; a first support provided on a first rotational machine axis, the first rotational axis being mounted on the base in a fixed position relative to the base; a second support provided on a second rotational machine axis, the second rotational axis being mounted on the base in a fixed position relative to the base, wherein the axis of rotation of the second rotational axis is parallel to and spaced laterally from the axis of rotation of the first rotational axis. A mount is carried by a support arm on the second support, with the support arm being moveable relative to the second support about a rotary axis.

Abstract: Various embodiments of a drill are described in which the drill includes an air motor assembly having an output spindle and a head attachment having a cutter spindle. The head attachment can be removably connected to the motor assembly, and capable of being configured in at least (i) a first mode in which the cutter spindle is parallel to the output spindle of the air motor assembly, and (ii) a second mode in which the cutter spindle is orthogonal to the output spindle of the air motor assembly.

Abstract: A drilling system may include a plurality of robotic drilling units. Each one of the robotic drilling units may include a drill end effector positioned inside a barrel section. The barrel section may be configured as a composite sandwich structure having an inner face sheet. The robotic drilling units maybe operable in synchronized movement with one another to drill a plurality of perforations into the inner face sheet using the drill end effectors in a manner providing a predetermined percent-open-area of the inner face sheet.

Abstract: A device for drilling side portions of large section members, the device being arranged in a cutting system for cutting individual section member lengths, starting from a long section member, comprises a base thereon swinging support arms extend, the support arms being arranged with a V pattern enclosing an angle (?), each support arm including a plurality of sliding rollers for causing the section member to slide thereon, the swinging arms including guides slidably supporting a controllably driven carriage operatively connected to a threaded screw, each threaded screw being operatively connected to a controllable motor, each carriage having a movable arm which may be controllably displaced along guides and comprising parallel guides engaging a drilling assembly operatively coupled to a driving shaft, each driving shaft being operatively connected to a corresponding controllable motor.

Abstract: In one respect, the invention is a coring machine for removing portions of food item blanks, the coring machine comprising a plate assembly for holding the food item blanks and a pair of coring assemblies, each comprised of a plurality of coring bits that are aligned with passages in the plate assembly.

Abstract: A machining device for a workpiece wherein a first feed axis extends through a workpiece holder, a first machining tool is disposed on a first side of the feed axis, and a second machining tool is disposed on a side of the feed axis opposing the first side. Between a first feed axis and perpendicular to a second feed axis, at least one machining tools has a predetermined fixed angular offset.

Abstract: A mechanical cutting device cuts twisted strips of foods such as potatoes. The device comprises twisted cutting tubes, each having a ring secured at a distance from the cutting end. A plurality of such tubes may be arranged in an array, which may be supported by plates having an array of tube-supporting orifices. The cutting tubes are supported for rotation in such manner that, when force is exerted on the tubes to insert the tubes into the food, the tubes rotate as they cut into the food obtaining as result twisted strips of food.

Abstract: A hole drilling device and method include a drilling head (61), a plurality of hole drilling tools (63) detachably attached to the drilling head (61), a driving device (64) for allowing the drilling head (61) to move in the radial direction and axial direction of attachment holes (60) to be formed on a tube sheet (45), and a control device (65) for driving the driving device (64). The hole drilling tools (63) are disposed, in relation to the drilling head (61), along the arrangement direction of the attachment holes (60) and at an equal interval from one another, said interval being an integer multiple equal to or greater than double the pitch of the attachment holes (60); and the control device (65) drives the driving device (64).

Abstract: The invention relates to a tool having a tool element which rotates in operation with at least one geometrically defined blade, in particular a material cutting tool element. The tool element is subject to an operating parameter in the operating condition. A measuring device is provided for determination and conversion of the operation parameter into a measured signal. A first measuring device cooperates with a first tool element in the operating condition such that essentially only a first operating parameter for the first tool element may be recorded by the first measuring device.

Abstract: Embodiments include a method and apparatus for drilling holes or cutting at specified locations on a beam or other material, even if the beam is offset from an ideal beam configuration. In some embodiments, the apparatus is configured to determine the correct locations of holes in the beam despite the beam's offset and drill holes in the beam according to this determination. The apparatus may be capable of drilling holes at specified locations on a web of an I-beam. In some embodiments, the method comprises determining the correct locations of the holes in the particular beam using the apparatus and drilling the holes in the correct locations in the beam according to that determination. Some embodiments include using one or more clamping mechanisms and one or more drilling members to determine the correct locations of the holes in the particular beam.

Abstract: A multi-spindle machining machine comprises a base including a working room to move a tool and a workpiece; a working head including a driving spindle disposed on a lower end thereof to clamp the tool; a carrier including a seat fixed on one side of the working room, a rotary shaft mounted on the seat laterally to drive the seat to rotate in an axial direction, a fixing holder connected to the rotary shaft to fix the workpiece to the fixing holder; a lateral driving device disposed on the base and located on one side of the working room in a horizontal direction to drive the working head to move in X and Y axes; a vertical driving device disposed on the base and located on another side of the working room in a lateral direction to drive the seat to move in Z axis direction.

Abstract: Disclosed is an automated drill apparatus composed of one or more gang drills mounted to a gang drill chassis, at least one powered drive wheel affixed to the gang drill chassis, and at least three pivotable support wheels. A control panel provides remote operation of drill rotation activation, drill advance, and drill bed position adjustment, and a panic off switch. A control system implements steering the automated drill apparatus and is selectable by the operator for steering in two-wheel mode or crab steer mode. The pivotable drive wheels, in conjunction with the control panel and control system, are used to position the automated drill apparatus along a slab to be drilled, and further activate one or more gang drills for drilling a slab.

Abstract: A threading machine for the end threading of long metal bars includes a peeler and a threader mounted co-axially on a spindle. The spindle is powered by a motor. A leading rod is attached to the clamping chariot. The leading rod includes the peeler opening and closing controller, and the threader opening and closing controller. The controllers are supported by a carriage set, and the threader is able to travel forward and backward. The peeler opening controller and threader opening controller are adjustable by moving them along leading rod to accommodate various thread length.

Abstract: A driving assembly for driving panels and plate elements in general to be processed comprises a central framework for supporting a driving chain continuously entrained on a driving pulley and an idle pulley, a plurality of panel driving shoes being coupled to the chain. The main feature of the invention is that the driving assembly further comprises, on a portion of an active arm of the driving chain, actuator elements for removing the drive shoes from a panel sliding plane, to allow a processing tool to perform a lot of desired machining operations on the panels.

Abstract: This invention is intended for gang drilling a predetermined pattern of holes, accurately located in a specifically sized pocket or mortise pre-created by other means in a wooden member such as, but not limited by, a door or door jamb, in which the purpose of these holes is to aid in attaching other physical devices such as, but not limited to, hinges by means of common wood screws. This invention is comprised of a system of roller chain-driven spindles which contain appropriately sized twist drill bits, all driven from a centrally located spindle attached externally to a standard hand-drill. An appropriately sized spring-loaded guide plate fits easily into the pre-created pocket or mortise allowing positive positioning of the invention's assembly but allows access for the twist drills to pass through the guide plate, for the purpose of drilling into the wood.

Abstract: This invention is intended for gang drilling a predetermined pattern of holes, accurately located in a specifically sized pocket or mortise pre-created by other means in a wooden member such as, but not limited by, a door or doorjamb, in which the purpose of these holes is to aid in attaching other physical devices such as, but not limited to, hinges by means of common wood screws. This invention is comprised of a system of roller chain-driven spindles which contain appropriately sized twist drill bits, all driven from a centrally located spindle attached externally to a standard hand-drill. An appropriately sized spring-loaded guide plate fits easily into the pre-created pocket or mortise allowing positive positioning of the invention's assembly but allows access for the twist drills to pass through the guide plate, for the purpose of drilling into the wood.

Abstract: An exemplary machine tool (20) includes a main equipment (30) and a plurality of peripheral equipments. The main equipment has a base (31) and a drill (34) disposed on the base. The peripheral equipments are separate from and connected to the main equipment. A precision of the machine tool does not worsened.

Abstract: A sleeve cutter is provided for precision cutting of a length of metal tubing or the like. The sleeve cutter includes a mandrel or spindle for supporting a tube-shaped sleeve thereon between a pair of rotary-driven cutting wheels adapted for movement together between retracted positions spaced outwardly from the mandrel, and advanced position with cutting edges in engagement with the mandrel-supported sleeve. Each cutting wheel further includes a shaping step or land for removing any burr or flare from the cut sleeve end.

Abstract: A production line for carrying out machining and cleaning operations on rectangular frameworks, is provided. Elongate plastic frame members are welded together in a welding machine, thereby forming two rectangular frameworks located one above the other. These are moved to a framework processing machine along separate predetermined paths with the first path being located above the second path. The paths are provided by horizontally extending guide arrangements on the machine which has a power tool for carrying out machining operations, this tool being supported by a transporting mechanism capable of moving the tool both horizontally and vertically. Machining steps are carried out on the two frame works while they are held one above the other. The frameworks are moved to a weld cleaning machine along respective upper and lower paths for further processing operations.

Abstract: The invention relates to a machine tool, in particular to cutting machine tools. The inventive machine tool comprises at least two machining modules provided with at least one spindle with a horizontally oriented axis and at least one clamping module having a tooling surface for at least one part which is horizontally oriented and rotatable around a vertical axis. The clamping module includes structure for a rigid coupling thereof to the machining module. One or several clamping modules and/or machining modules are provided with at least one fictive midplane which is parallel with respect to the spindle axis. The machine tool also includes at least one pallet changing module which is connected to the clamping module asymmetrically with respect to the midplane.

Abstract: A drill comprising: a power head having a first chuck positioned on a first end and a second chuck positioned on an opposite second end of the power head; a handle attached to the power head, the handle having a trigger switch for controlling a drive motor coupled to the first and second chucks.

Abstract: A machine tool apparatus is provided employing a plurality of tool heads which may be sequentially or simultaneously automatically controlled to perform preprogrammed operations on either the same or different workpieces. In one form, a plurality of tool heads are supported on the same frame, guideway or track and may be separate prepositioned or driven under remote or automatic control to perform preprogrammed operations wither in sequence or simultaneously on the same workpiece or simultaneously on separate workpieces spaced apart on a common conveyor such as a flight conveyor while the conveyor is either in motion or stationary. In another form, the conveyor is automatically stopped with units of work thereon, each disposed so as to be predeterminately located with respect to a respective machine tool which has been prepositioned adjacent the work-holding conveyor.

Abstract: In a method and apparatus for perforating multiwall polymeric cylindrical tubing, a drill head is slidably mounted for reciprocating movement on a support frame between inlet and outlet stations, the drill head having at least one drill for forming an opening in the wall of a length of unperforated tubing. The unperforated tubing is advanced along an axial path and a length thereof positioned in the drill head. The drill head and unperforated tubing are advanced simultaneously from the inlet to the outlet station, in unison and at the same speed, and without clamping the tubing. During this movement, the drill is actuated whereby to form an opening in the tubing material. At the outlet station, the perforated tube material is discharged from the drill head and the drill head is returned to the inlet station receive the next succeeding section of unperforated tubing and repeat the process.

Abstract: A driving assembly for driving a plurality of mandrels comprises a supporting carriage supporting a plurality of mandrels, adjoining one another along a parallel direction to the carriage driving direction, and clamping means for removably clamping the individual mandrels at a withdrawn position thereof, as well as driving means for driving the individual mandrels, which can be actuated as a mandrel is arranged at an advanced position.

Abstract: A method and apparatus for dice manufacture including robotic manipulation of a work piece to obviate manual handling and reduce risk of worker injury.

Abstract: A reconfigurable multi-spindle apparatus for use with a machining device in a plurality of configurations across part families. In one embodiment, the reconfigurable multi-spindle apparatus may include at least two spindle head modules, a mechanism for transmitting power between the spindle head modules, and a mechanism for reconfigurably connecting the spindle head modules such that the multi-spindle apparatus is reconfigured from a first configuration to a second configuration across part families. An embodiment of a spindle head module may include two tool holders and a mechanism for adjusting the distance between the tool holders such that the multi-spindle apparatus is reconfigured within a part family.

Abstract: A system for making aerated concrete blocks produces such blocks having at least one passageway therein. The system may comprise a molding station for receiving materials for making aerated concrete and for allowing the materials to rise and stiffen into a body, a dividing station downstream from the molding station for dividing the body into an array of blocks, and a curing station downstream from the dividing station for curing the array of blocks. Moreover, the manufacturing system also preferably includes a drilling station downstream from the curing station to drill the at least one passageway extending through each of the blocks. The passageways provide easier grasping by the mason, reduce the weight without significantly compromising strength, and may be aligned in a wall during construction at a building site to facilitate the placement of vertical reinforcing members in the wall. The drilling station may drill a plurality of spaced apart passageways through each block.

Abstract: A workpiece is assembled by removably mounting an alignment tool to a conventional wing structure so that the alignment tool holds multiple conventional strut fittings to the wing structure. A frame of a CNC manufacturing machine is moved to and removably mounted to the workpiece. The orientation of the workpiece with respect to the frame mounted thereto is quantified. A predetermined pattern of operations to be performed by the CNC manufacturing machine to form attachment holes for use in attaching the strut fittings to the wing structure is adjusted to compensate for the orientation of the workpiece relative to the frame. Thereafter, the CNC manufacturing machine automatically forms the attachment holes.

Abstract: In a multiple spindle processing unit which can change processing locations of a work in accordance with a modification made to the work, the present invention is intended to facilitate changes of design corresponding to the modification made to the work and reduce the number of parts to be replaced. In a frame member which is guided and supported so as to be moved towards and away from a work, insertion holes are formed at a plurality of locations corresponding to processing locations of the work. In each of a plurality of tool main spindle assemblies, a main spindle having a front end portion where a chuck for mounting a tool is provided is coaxially journaled in a housing in the shape of a circular cylinder or a polygonal cylinder and is rotationally driven by a built-in motor. Each of the tool main spindle assemblies is mounted to the frame member with the housing inserted through the insertion hole.

Abstract: A machining head (36) is drivable along a vertical axis and two horizontal axes with respect to a workpiece held on a workpiece-holding device, and has, at progressively lower levels along said vertical axis, one or two high-speed spindles (44), one or two low-speed spindles (46) and one or two feed-out spindles (48), all arranged at right angles to said vertical axis and driven by one or more motors (42) mounted on the head. The machining head can bring the high-speed spindles to cooperate with a tool-changing magazine (52). The workpiece-holding device (54; 154) is adapted to carry two sets of workpieces on respective supports (56, 58; 170), and to shift said supports in succession between a working position near the head and a tool-changing position remote from the head.

Abstract: Method and device for drilling holes into a mantle of a cylinder of a paper machine, in particular a drying cylinder, while the cylinder is in its site of operation in the paper machine in which a drill carriage having drill bits is supported on the cylinder being drilled. The drill carriage is locked in a fixed position relative to the cylinder being drilled the drill bits are pressed into the mantle of the cylinder to be drilled and rotating to thereby drill holes in the cylinder mantle. The drill carriage is supported on the cylinder being drilled by a first set of wheels arranged on the drill carriage during drilling and is displaced upon rotation of a second set of wheels which contact the cylinder only for axial movement and not during drilling.

Abstract: An attachment that allows a drilling machine, such as a drill press, to simultaneously bore the plurality of holes required for mounting a hardware component to a workpiece. In an exemplary embodiment, the attachment is adapted to simultaneously bore, in a desired disposition, all three holes needed to mount European style hinges in a single stroke. The hinge boring attachment includes a drilling head, which attaches to the chuck of the drilling machine. The drilling head rotatably supports a plurality of boring bit mounting shafts, corresponding to the number of holes to be drilled and interconnected with drive trains for translating the rotation of a center shaft, attached to the chuck of the drilling machine, to all shafts. A stabilizing arm is further preferably provided to clamp the drilling head to the support post of the drill press and roll smoothly along the support post during the drilling operation.

Abstract: The drilling machine has a cross member along which slide two carriages supporting two machining heads; the two carriages are moved independently of each other along the X axis; one of the two machining heads is fitted to the respective carriage by means of a slide which is also moved along the Y axis by an electric motor controlled by a numeric-control unit; the maximum travel of the slide is at least twice the pitch of the rows in the matrix of holes in the printed circuit boards; and the movement of the slide provides for both setting the two machining heads along the Y axis, and enabling the two machining heads to simultaneously drill two adjacent rows in the matrix of holes.

Abstract: In a thermal equalization system a machine tool carriage preferably of aluminum but which could be made of other lightweight materials, a drilling spindle housing is mounted on the carriage. At least one spindle housing is be mounted said carriage to service work pieces mounted on a tooling plate of the work table for said spindle. The chiller unit is used to provide coolant to the spindle to compensate for the heat generated by the spindle during drilling. When the spindle is not drilling, excessive cooling of the spindle can result. Accordingly, the instant invention also includes, a conductive rubber heating pad which is attached to the spindle structure to provide a heat source for the system to compensate for excessive cooling when the drill is not generating heat. The temperature control maintains the temperature between the spindle housing, carriage and work table thereby minimizing temperature expansion differentials between the drilling position and the worktable position.

Abstract: A long length product is conveyed by a conveyor to a propulsion mechanism into contact therewith. The product is gripped by a first conveyor line vise and cut at its tailing end side into a specified dimension. The product is advanced by the propulsion mechanism against the conveying force of the conveyor and then gripped by the first conveyor line vise and machined. A series of these operations are iterated. Finally, the product is advanced to a second conveyor line side, where it is gripped by a second conveyor line vise and subjected to final machining with the propulsion mechanism retreated. Instead of using a process of cutting to cut the leading end side of the product to a specified dimension, the leading end side of the product may be put into contact with the stopper and fed by referencing the leading end of the product.

Abstract: A method for drilling holes into a mantle of a cylinder of a paper machine while the cylinder is in its site of operation in the paper machine. The holes are drilled into the cylinder mantle by a drilling device having drill bits and which is transferred after each drilling cycle to the next drilling position. When drilling the holes, the device is supported on cylinders placed adjacent to and above the cylinder to be machined and/or on the cylinder to be machined by fastening supports of the device. Before the drilling is started, the device is locked in its position by locking fastening supports in a desired position and, the holes are drilled into the cylinder placed underneath from the top toward the bottom.

Abstract: The present invention relates to the multi-splindle machining apparatus which carries out machining of the discontinuous surfaces of a plurality of workpieces simultaneously, and in order to restrain the amplification of chattering, oscillation or the like so as to prevent the machining precision from deterioration, the diameters of plural drive pulleys 7a, 7b, 7c connected to a driving motor are finely varied to change at random the rotational speeds which are transmitted from the drive pulleys 7a, 7b, 7c through belts 10 to driven pulleys 8 provided on each machining spindle 3a, thus changing irregularly the timings at which cutting edges 9 of the machining spindles 3a pass the discontinuities such as joint portions s.

Abstract: A toolhead assembly for a machine tool generally consisting of a housing supportable on the machine tool and having at least one elongated bore therein, a liner formed of a structural polymer material disposed in the bore, adhesively secured to the housing and having a cylindrical inner wall surface, a spindle shaft journal in the housing and disposed coaxially in the liner for axial displacement therein, the spindle shaft having a head section rigidly mounted on the spindle shaft and engagable in sliding relation to the liner inner wall to provide fluid chambers on either side thereof, means for injecting fluid under pressure selectively into the chambers for axially displacing the spindle shaft, means for spinning the spindle shaft about its axis and means for securing a tool bit to the spindle shaft.

Abstract: A multispindle thread cutter apparatus is proposed, which has a drive shaft (3) to be driven by motor and which has a plurality of work spindles (4). Interposed between the drive shaft (4) and the work spindles (4) is a distributor and reversing gear (33), by way of which the work spindles (4) are driven to rotate by the drive shaft (3). Each work spindle (4) is assigned its own single reversing coupling (34), which has its own single switchover device (35), so that the directions of rotation of the work spindles (4) can be reversed while the drive shaft (3) continues to rotate uninterruptedly in the same direction.

Abstract: A slider 16 having a cutting insert 5A is slidably mounted in a groove 11 formed along the generatrix dimension of a substantially conical tool body 1. Serrations 12 and 16a, which are brought into close contact with each other for engagement, are formed on one side surface 11a of the groove 11 and on one side surface of the slide 16 opposite thereto. A wedge member 13 is detachably mounted between the other side surface 11b of the groove 11 and the slider 16 and is pressed against the side surface 11a so as to cause the serrations 12 and 16 to be engaged with each other. No special shaping accuracy is needed for the groove 11 or the slider 16 since any shaping error in these members can be absorbed so that a sufficient mounting accuracy is ensured for the slider 16. Thus, it is possible to reduce the requisite labor, etc. for the shaping of these members while maintaining the requisite positional accuracy for the cutting insert 5A.

Abstract: A toolhead assembly for a machine tool generally consisting of a housing supportable on the machine tool and having at least one elongated bore therein, a liner formed of a structural polymer material disposed in the bore, adhesively secured to the housing and having a cylindrical inner wall surface, a spindle shaft journal in the housing and disposed coaxially in the liner for axial displacement therein, the spindle shaft having a head section rigidly mounted on the spindle shaft and engagable in sliding relation to the liner inner wall to provide fluid chambers on either side thereof, means for injecting fluid under pressure selectively into the chambers for axially displacing the spindle shaft, means for spinning the spindle shaft about its axis and means for securing a tool bit to the spindle shaft.

Abstract: A drilling device for boring holes in wood, plastic or metal in precise locations on a work piece, comprising a set of geared together shafts equipped with drilling bits. The bit holder shafts are guided by bearings housed in a frame biased upwardly by springs. The geared together shafts being powered by an electric drill motor.

Abstract: To retool drilling machines having at least two drill spindles with coupling members for drill bits with a different pattern of drilled holes, an adapter is provided including a housing with two mutually parallel input shafts whose distance apart corresponds to the distance between the two drill spindles and whose form is the same as drill bits to be inserted into the two drill spindles. On the opposite housing side, two drill spindles or groups of drill spindles to be connected together by transmission means are arranged which have chuck members for drill bits, of which each or each group is connected in a driving manner with one of the two input shafts.

Abstract: An in line drilling device for boring holes an equal distance from one another in wood, plastic or metal, comprising a set of geared together shafts equipped with drilling bits. The bit holder shafts are guided by bearings housed in a frame biased upwardly by springs. The fully compressed springs act to limit the extent of projection of the drill bits into a workpiece.

Abstract: A rotating dual attachment receptacle apparatus tool which allows the operator to use more than one tool accessory without the need of frequent changing of the drilling, driving or fastening accessory. The rotating apparatus tool has three (3) major parts: a stem grip housing having a motor and power means disposed therein; a safety guard housing attached to one end of the stem grip housing and a rotating drill head assembly disposed within the safety guard housing. The rotating drill head assembly has two (2) conventional drill chucks located at opposite ends thereof and is held in place within the cavity of the safety guard housing by means of a main drive shaft which extends from the top inside portion of the safety guard housing into the stem grip housing. The rotating drill head assembly is so constructed that it can be rotated in a 360 degree plane about the longitudinal axis of the main drive shaft.

Abstract: The invention is directed to a method of forming a large number of holes in a given area. A plurality of tools spaced along X and Y axes are used to form holes simultaneously, and the tools are successively moved in steps to drill more holes.

Abstract: A steel sheet (10) having a stress-relief annealed, structure with a plurality of magnetic domains (12) is made by drilling a plurality of closely spaced, small holes (15) through the entire thickness of the steel sheet, where the drilling is effective to form additional domain walls (17) and subdivide the magnetic domains.