Seco Tools’ Inspiration Through Innovation (ITI) event returns this month, marking a decade of breakthrough collaborations in aerospace and medical manufacturing. This year’s in-person gathering held on October 16th and 17th promises cutting-edge insights into overcoming shared challenges and propelling the next generation of innovation.

B+W builds its tables with a large INA (Schaeffler Group) ZKXDF or ZKLDF angular-contact thrust ball bearing of diameter between 460 and 725mm, depending on machine model. Construction height of the table is low despite the high power, maximising the machining envelope.

Greenfield, Massachusetts-based The duMont Co. purchased Hassay-Savage in 2017 to make it part of duMont’s Pilot Precision Products Group. Hassay-Savage makes CNC single-point broaches, which are application-specific tools, and CNC broaching systems with tool bodies that accept multiple specialized inserts for jobs.

Centering and alignment also can be challenging. Rotary broaching is well suited for making small forms like hexagons and squares in soft materials, such as aluminum, brass and mild steel. However, when it comes to aligning multiple holes using a rotary broaching tool, the operation is extremely demanding, Derbin said. Most rotary broach holders have a free-turning spindle, which does not allow alignment of the holes. He said it is important to center the rotary broach as closely as possible to the middle of the workpiece. If not properly centered, users may experience oversized forms or uneven form configurations.

For instance, broaching an internal hexagon, square, Torx or keyway in a blind-hole with a traditional linear broach is not feasible. Unlike conventional broaching in which a broach is pulled through the entire length of the part, thus requiring a through-hole, rotary broaching allows the machining of polygon forms into a blind-hole at the end of a workpiece. This process can be achieved in seconds on any mill, lathe or vertical machining center.

Alternatively, an adapter plate may be similarly delivered by the ATC and clamped hydraulically to the spindle head using the same four-point mechanism. It takes all the weight of a heavy angle head, boring bar, NC facing head or other driven tool needed to carry out special machining operations like drilling multiple or awkwardly positioned holes, facing, grooving, profiling features such as a stepped bore, or turning an internal or external taper or sphere.

Modern broaching dates to the 19th century, and the technology remained pretty straightforward for most of the ensuing years. But today, the more than 150-year-old technology has entered a new millennium with tool systems that allow broaching to be integrated into today’s CNC machining environment. Parts now can be broached in a linear or rotary process and machined in one setup, not as a secondary operation. Typically, broaching part features on a CNC machine is done at a fraction of the cost of traditional methods.

In numerical-control applications, a cut shorter than the programmed cut resulting after a command change in direction. Also a condition in generated gear teeth when any part of the fillet curve lies inside of a line drawn tangent to the working profile at its point of juncture with the fillet. Undercut may be deliberately introduced to facilitate finishing operations, as in preshaving.

Machine designed specifically to run broaching tools. It is typically designated by operating characteristics (pull, push, rotary, continuous, blind-spline), type of power used (hydraulic, mechanical) and tonnage ratings. Broaching is also performed on arbor presses (manual and powered).

In fact, broaching may be done on any machine with a turning center, including manual machines, such as Bridgeports, and screw machines, said Steve Derbin, owner and sales manager at Fort Myers, Florida-based Polygon Solutions Inc. Its product line features a rotary broach, which cuts a part’s full form one corner at a time in one pass without the need for a secondary operation.

“Now, instead of changing the broaching, you just change the tips on the holders,” said Fred Wanat, engineering and production manager at Hassay-Savage Co., Turners Falls, Massachusetts. “This gives you more flexibility and more options to be able to broach different features.”

Operation in which a cutter progressively enlarges a slot or hole or shapes a workpiece exterior. Low teeth start the cut, intermediate teeth remove the majority of the material and high teeth finish the task. Broaching can be a one-step operation, as opposed to milling and slotting, which require repeated passes. Typically, however, broaching also involves multiple passes.

The sole sales and service agent for B+W machines in Britain, Ireland and the Gulf, Kingsbury, has put together a PowerPoint presentation outlining how the system works, a copy of which is available on request.

Quay Lane PO12 4LB UNITED KINGDOM

Microprocessor-based controller dedicated to a machine tool that permits the creation or modification of parts. Programmed numerical control activates the machine’s servos and spindle drives and controls the various machining operations. See DNC, direct numerical control; NC, numerical control.

Dustcontrol UK is set to exhibit its innovative dust extraction solutions at the Advanced Engineering Show 2024, taking place at the NEC Birmingham from 30-31 October.

The SK-51 Type A fixed head lathe from Star Micronics GB is a 2-inch bar capacity slant-bed machine equipped with twin 12-station turrets, offering 7.5kW powered driven tools on every station.

In tensile testing, the ratio of maximum load to original cross-sectional area. Also called ultimate strength. Compare with yield strength.

Five-channel hydraulic transfer is possible up to maximum rpm. The table motor stator and rotor are actively cooled by a water-glycol mixture to prevent thermal movement.

Image

While the spindle is rotating, the effects of these loads are dissipated across each ball or roller bearing within the spindle assembly. However, when the spindle is static, for example when it is holding a turning tool, the loads and vibrations can cause premature wear and eventually lead to expensive repair or replacement.

For example, a bone screw might require a hexagon, hexalob or Torx shape machined into the part. These options can be broached into the end of the bone screw with a ±0.0005" tolerance.

The broaching process traditionally is a stand-alone operation. Broaching can effectively generate finished shapes in one pass. This is especially true of jobs that require long production runs—that is, jobs that don’t need many tool changes.

As an option, a tool extension unit can be automatically exchanged into the spindle to extend the reach of short cutters, minimising the number of long tools in the magazine that may be needed for certain applications. The unit also provides more rigidity than long-reach cutters, optimising damping and avoiding the risk of vibration and chatter. Quill movement with length and sag compensation is a further option for machining particularly difficult inner contours.

A German manufacturer has developed an ingenious method for relieving the spindle bearings from radial and axial forces when turning operations are in progress on its machining centres. The system provides further spindle protection by supporting heavy driven tools. PES reports.

CNC machine tool capable of drilling, reaming, tapping, milling and boring. Normally comes with an automatic toolchanger. See automatic toolchanger.

The table bearing absorbs a high tilting moment up to 45,000Nm. Pallet positioning is to within 10µm, assisted in part by automatic cleaning of its underside and the pallet clamping surface before exchange.

The coupling area is thoroughly cleaned with coolant and air before final engagement. As the entire process is autonomous, there is no operator intervention or interruption to the production cycle.

Pallet load can be up to four tonnes when turning at maximum rotational speed of 300rpm. Software is included in the control as standard for actively balancing the loaded table, with monitoring provided by imbalance sensors.

Turning machine capable of sawing, milling, grinding, gear-cutting, drilling, reaming, boring, threading, facing, chamfering, grooving, knurling, spinning, parting, necking, taper-cutting, and cam- and eccentric-cutting, as well as step- and straight-turning. Comes in a variety of forms, ranging from manual to semiautomatic to fully automatic, with major types being engine lathes, turning and contouring lathes, turret lathes and numerical-control lathes. The engine lathe consists of a headstock and spindle, tailstock, bed, carriage (complete with apron) and cross slides. Features include gear- (speed) and feed-selector levers, toolpost, compound rest, lead screw and reversing lead screw, threading dial and rapid-traverse lever. Special lathe types include through-the-spindle, camshaft and crankshaft, brake drum and rotor, spinning and gun-barrel machines. Toolroom and bench lathes are used for precision work; the former for tool-and-die work and similar tasks, the latter for small workpieces (instruments, watches), normally without a power feed. Models are typically designated according to their “swing,” or the largest-diameter workpiece that can be rotated; bed length, or the distance between centers; and horsepower generated. See turning machine.

Mindful of this, Burkhardt + Weber (B+W) has introduced a hydraulically-actuated, four-point clamping system on the spindle head of its heavy-duty, multi-tasking machines for use during turning operations.

Broaching the serration is a two-step operation. In the first step, the spindle does not move, and the broaching tool feeds three times until the first tooth is entirely established. During the second step, the spindle starts indexing, and the successive teeth continuously broach until the finished depth is reached.

Another area often considered challenging when broaching relates to a material’s tensile strength, which can be a major factor for how a workpiece material responds during broaching. The higher the tensile strength, the lower the odds of successful broaching. But that rule of thumb is changing, Wanat said. A TiN coating helps the broach perform well under high-load conditions and when broaching difficult-to-machine materials, such as those found in the medical industry.

Hassay-Savage offers a slew of standard broaches in various dimensions and can create specials. In addition, the company produces kits that include the tooling and accessories for particular applications. One kit is the AR15/M16 Magwell Kit for broaching the magazine well of a gun. Instead of buying a specialized $100,000 broaching machine and an $8,000 broach—assuming that the job is big enough to justify the expense—end users purchase a $4,000 kit suitable for lower-volume work and use the kit on standard CNC machines, Wanat said.

The evolution of the technology continued as broaching systems featuring indexable-insert broaching tools and toolholders were introduced. These holders accept multiple specialized inserts for customers’ particular applications.

The benefits of broaching on a CNC machine include fast speeds to create final forms, high accuracy, low heat, high repeatability and easy operation utilizing standard drilling G code. Broaching on a CNC machine also eliminates the need for secondary operations, such as wire EDMing, Derbin said.

Turning cutters are exchanged automatically from the magazine into the adapter in the holder plate using the same ATC, as the identical HSK-A100, SK50 or CAT50 back-end is used for the turning toolholders as for prismatic machining. Even when clamping very long turning tools, the holder plate ensures a rigid tool interface. All operations are fully integrated into the Siemens Sinumerik 840D sl control.

Broaches “can be used in low- and high-production environments and can be coupled to a driven head that increases broaching speeds by more than 300 percent,” Hagopian said.

Broaching jobs that can be performed on a CNC machine include internal and external profiles and various shapes, such as hexagons, squares, splines, Torx, Rosan, Torx Plus, double (hexagons, D’s, squares and keyways), single D’s, serrations, triangles, letters, numbers and custom forms made from a variety of materials.

The SK-51 Type A fixed head lathe from Star Micronics GB is a 2-inch bar capacity slant-bed machine equipped with twin 12-station turrets, offering 7.5kW powered driven tools on every station.

Broaching applications on CNC equipment are diverse and growing. For instance, Elgin, Illinois-based Schwanog LLC, a producer of insertable form tools, developed a broaching tool for creating serrations on turned parts using CNC equipment. In conventional machining, the production of serrations on turned parts requires a separate process. With this tool, people are able to use a new approach on a conventional lathe with a C-axis in a single operation.

Experience the precision and quality of DMG Mori’s machining process for a stainless steel surgical hammer in full in this hour long video.

The Magwell Kit eliminates the need for a secondary offline application. Most magwell broaching currently is done in a two-step process that requires rough milling on a CNC machine and then finishing on a vertical broaching machine. Using tools in the kit, which includes three tool bodies and three types of inserts, saves time and money by not necessitating a dedicated machine and operator.

Over time, as CNC technology developed, end users wanted to integrate broaching into CNC equipment so they could apply other cutting tools in the same machine. Broaching companies designed tools, tool bodies and holders that could be incorporated into this CNC environment. In one setup, users could achieve precise cuts and reduce the potential for tolerance stackup that occurs when having to move parts from machine to machine. CNC and rotary broaching had arrived.

Runs endmills and arbor-mounted milling cutters. Features include a head with a spindle that drives the cutters; a column, knee and table that provide motion in the three Cartesian axes; and a base that supports the components and houses the cutting-fluid pump and reservoir. The work is mounted on the table and fed into the rotating cutter or endmill to accomplish the milling steps; vertical milling machines also feed endmills into the work by means of a spindle-mounted quill. Models range from small manual machines to big bed-type and duplex mills. All take one of three basic forms: vertical, horizontal or convertible horizontal/vertical. Vertical machines may be knee-type (the table is mounted on a knee that can be elevated) or bed-type (the table is securely supported and only moves horizontally). In general, horizontal machines are bigger and more powerful, while vertical machines are lighter but more versatile and easier to set up and operate.

While some materials might be challenging to broach, it does not mean that these materials cannot be broached, according to Derbin.

Polygon Solutions’ proprietary rotary broach brake is a new mechanical solution for aligning broached forms. In addition, the company’s toolholders are adjustment-free and require minimal setup.

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Larry Adams is a freelance writer who has written extensively about manufacturing. Contact him at larryladams1@gmail.com.

Meanwhile, a video is available to view at: www.kingsburyuk.com/video/burkhardtweber-mct-1000. The content is based on a 5-axis, twin-pallet MCT1000 horizontal-spindle, universal machining centre with 2,200 x 1,400 x 1800mm working volume.

Workpiece is held in a chuck, mounted on a face plate or secured between centers and rotated while a cutting tool, normally a single-point tool, is fed into it along its periphery or across its end or face. Takes the form of straight turning (cutting along the periphery of the workpiece); taper turning (creating a taper); step turning (turning different-size diameters on the same work); chamfering (beveling an edge or shoulder); facing (cutting on an end); turning threads (usually external but can be internal); roughing (high-volume metal removal); and finishing (final light cuts). Performed on lathes, turning centers, chucking machines, automatic screw machines and similar machines.

It eliminates both the radial and axial forces on the spindle, the former being particularly damaging and prevalent during facing operations or when grooving or profiling a bore. The result is minimal spindle wear during high accuracy mill-turning of components in a single set-up.

Manufactured in-house at the machine tool manufacturer's Reutlingen factory, the rigid holder provides full support of static turning tools, absorbing the radial and axial machining loads that would normally be placed on the spindle bearings and transmitting them into the much more robust spindle head structure.

The fourth CNC axis is an infinitely-adjustable, ± 225° swivelling head rotating about a 45° plane and containing a 41kW/8,000rpm/1,400Nm spindle, while a 300rpm torque table provides the fifth CNC axis.

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Machining operation in which metal or other material is removed by applying power to a rotating cutter. In vertical milling, the cutting tool is mounted vertically on the spindle. In horizontal milling, the cutting tool is mounted horizontally, either directly on the spindle or on an arbor. Horizontal milling is further broken down into conventional milling, where the cutter rotates opposite the direction of feed, or “up” into the workpiece; and climb milling, where the cutter rotates in the direction of feed, or “down” into the workpiece. Milling operations include plane or surface milling, endmilling, facemilling, angle milling, form milling and profiling.

The rotary broach brake is a simple device used to keep a broaching spindle tight enough to hold orientation but loose enough to allow the spindle to turn while broaching.  Image courtesy of Polygon Solutions

1. Process of locating the center of a workpiece to be mounted on centers. 2. Process of mounting the workpiece concentric to the machine spindle. See centers.

CNC broaches come in many forms. According to Hagopian, the different types of CNC broaches include rotary, or wobble, broaches, which are typically applied on a lathe or Swiss-style machine using a specialized holder but also can be used on a mill. Additional types include index, or punch, broaches, which are primarily applied on Swiss lathes utilizing the subspindle for “free machining.” Single-point broaching is performed on lathes or mills typically to generate a keyway or square radiused corners. Lastly, indexable broaches, which are used on lathes, Swiss machines and mills, can be produced in any shape or size to create features that range from a standard keyway to a complex profile with multiple radii and even splines.

These benefits are being realized by manufacturers across a large swath of sectors. Wanat said one growth area is in the medical and dental industries, which broach using Swiss-style CNC machines.

Before the turning element of a machining cycle commences, a customisable tool holder plate with a large, 160mm diameter contact area is transported by the automatic tool changer (ATC) to the four-point clamping system on the front of the spindle head, where the holder is hydraulically retained.

TW Ward CNC Machinery (Ward CNC) is pleased to announce that Andrew Elliott has rejoined the company in the sales department and senior management team.

These special inserts are for broaching magwells. The Hassay-Savage AR15/M16 Magwell Kit comes with three tool bodies, three types of inserts, two drivers and an alignment tool. Image courtesy of Hassay-Savage

Added to titanium-carbide tooling to permit machining of hard metals at high speeds. Also used as a tool coating. See coated tools.

Tapered tool, with a series of teeth of increasing length, that is pushed or pulled into a workpiece, successively removing small amounts of metal to enlarge a hole, slot or other opening to final size.

Seco Tools’ Inspiration Through Innovation (ITI) event returns this month, marking a decade of breakthrough collaborations in aerospace and medical manufacturing. This year’s in-person gathering held on October 16th and 17th promises cutting-edge insights into overcoming shared challenges and propelling the next generation of innovation.

“CNC broaching allows job shops and OEMs to have completed parts in as little as a single operation and single day,” said Matt Hagopian, vice president of business development for Hassay-Savage. “This is a huge competitive advantage and allows higher profitability for machine shops with limited capabilities.”

With the B+W solution, similar technology is available to address one-hit production applications involving much more rigorous machining of larger components made of tougher materials.

During metalcutting, the bearings in a machining centre spindle are subjected to a load from the side and another along the spindle axis, as well as resonance from the cutting process.

The rotary table on the MCT1000 may be used for 5-axis simultaneous prismatic metalcutting or positioning components for 5-sided machining, but for turning operations its dynamic, backlash-free, 55kW torque drive rated at 4,200Nm is its defining feature.

Jaguar Land Rover (JLR) is investing £500m to transform its historic Halewood facility into a state-of-the-art production site for electric vehicles (EVs), the company announced in September.

Multi-tasking on a milling/drilling centre by turning a component on the rotary table with a static turning tool clamped in the spindle in a single set-up is commonplace, but most configurations on the market tend to be based on light- to medium-sized platforms.

Experience the precision and quality of DMG Mori’s machining process for a stainless steel surgical hammer in full in this hour long video.

The travelling-column machine design allows the X-axis to be hydraulically clamped by a large brake disc during turning for extra rigidity and machining accuracy. As the X-axis does not move during the turning section of a cycle, motion control is drive-friendly and energy efficient.

New materials, enhanced processes and other advances are happening fast. As broaching technologies solve systemic challenges, this longtime production process should remain a productive option for quite some time.

“As long as your toolholder block on your turret or your machine spindle on your mill is centered with your workpiece by 0.0002", you can simply insert our toolholder and clamp it down,” Derbin said.

The broaching tool carries a quarter-circle geometry with multiple teeth. Only the first tooth carries a complete finish-depth profile while the remaining teeth are for roughing.

“Opening up your pre-drill diameter or broaching a shallow depth may allow you to achieve rotary broaching on certain materials,” he said. “However, broaching these materials can reduce the rotary broach tool life. As technology improves and testing continues on various materials, we are confident that we will soon be able to recommend additional materials that can be broached using rotary broaching.”

Secures a cutting tool during a machining operation. Basic types include block, cartridge, chuck, collet, fixed, modular, quick-change and rotating.

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As the spindle is not subject to excessive moments of force by having to support large cutters, the bearings are protected and are subject to less wear. A three-point clamping system is alternatively available if the tools to be supported are lighter.

Derbin advised keeping a few things in mind when broaching a blind-hole. If possible, drilling needs to be slightly deeper than the depth of the form to be broached. This allows room for chip accumulation at the bottom of the hole. An undercut ideally should be added so chips can freely break away.

A German manufacturer has developed an ingenious method for relieving the spindle bearings from radial and axial forces when turning operations are in progress on its machining centres. The system provides further spindle protection by supporting heavy driven tools. PES reports. During metalcutting, the bearings in a machining centre spindle are subjected to a load from the side and another along the spindle axis, as well as resonance from the cutting process. While the spindle is rotating, the effects of these loads are dissipated across each ball or roller bearing within the spindle assembly. However, when the spindle is static, for example when it is holding a turning tool, the loads and vibrations can cause premature wear and eventually lead to expensive repair or replacement. Mindful of this, Burkhardt + Weber (B+W) has introduced a hydraulically-actuated, four-point clamping system on the spindle head of its heavy-duty, multi-tasking machines for use during turning operations. It eliminates both the radial and axial forces on the spindle, the former being particularly damaging and prevalent during facing operations or when grooving or profiling a bore. The result is minimal spindle wear during high accuracy mill-turning of components in a single set-up. The sole sales and service agent for B+W machines in Britain, Ireland and the Gulf, Kingsbury, has put together a PowerPoint presentation outlining how the system works, a copy of which is available on request. Meanwhile, a video is available to view at: www.kingsburyuk.com/video/burkhardtweber-mct-1000. The content is based on a 5-axis, twin-pallet MCT1000 horizontal-spindle, universal machining centre with 2,200 x 1,400 x 1800mm working volume. The fourth CNC axis is an infinitely-adjustable, ± 225° swivelling head rotating about a 45° plane and containing a 41kW/8,000rpm/1,400Nm spindle, while a 300rpm torque table provides the fifth CNC axis. Heavy hitter Multi-tasking on a milling/drilling centre by turning a component on the rotary table with a static turning tool clamped in the spindle in a single set-up is commonplace, but most configurations on the market tend to be based on light- to medium-sized platforms. With the B+W solution, similar technology is available to address one-hit production applications involving much more rigorous machining of larger components made of tougher materials. The tool holder plate is hydraulically secured and a turning tool is automatically inserted into the spindle by the same ATC mechanism. The tool holder plate absorbs all the axial and radial forces generated during turning; none are transferred to the spindle bearings Before the turning element of a machining cycle commences, a customisable tool holder plate with a large, 160mm diameter contact area is transported by the automatic tool changer (ATC) to the four-point clamping system on the front of the spindle head, where the holder is hydraulically retained. The coupling area is thoroughly cleaned with coolant and air before final engagement. As the entire process is autonomous, there is no operator intervention or interruption to the production cycle. Manufactured in-house at the machine tool manufacturer's Reutlingen factory, the rigid holder provides full support of static turning tools, absorbing the radial and axial machining loads that would normally be placed on the spindle bearings and transmitting them into the much more robust spindle head structure. Turning cutters are exchanged automatically from the magazine into the adapter in the holder plate using the same ATC, as the identical HSK-A100, SK50 or CAT50 back-end is used for the turning toolholders as for prismatic machining. Even when clamping very long turning tools, the holder plate ensures a rigid tool interface. All operations are fully integrated into the Siemens Sinumerik 840D sl control. Support for driven as well as static tools Alternatively, an adapter plate may be similarly delivered by the ATC and clamped hydraulically to the spindle head using the same four-point mechanism. It takes all the weight of a heavy angle head, boring bar, NC facing head or other driven tool needed to carry out special machining operations like drilling multiple or awkwardly positioned holes, facing, grooving, profiling features such as a stepped bore, or turning an internal or external taper or sphere. As the spindle is not subject to excessive moments of force by having to support large cutters, the bearings are protected and are subject to less wear. A three-point clamping system is alternatively available if the tools to be supported are lighter. Even when using long turning tools, the holder plate ensures a rigid tool interface, avoiding vibration and ensuring excellent dimensional accuracy and surface finish As an option, a tool extension unit can be automatically exchanged into the spindle to extend the reach of short cutters, minimising the number of long tools in the magazine that may be needed for certain applications. The unit also provides more rigidity than long-reach cutters, optimising damping and avoiding the risk of vibration and chatter. Quill movement with length and sag compensation is a further option for machining particularly difficult inner contours. About B+W torque tables The rotary table on the MCT1000 may be used for 5-axis simultaneous prismatic metalcutting or positioning components for 5-sided machining, but for turning operations its dynamic, backlash-free, 55kW torque drive rated at 4,200Nm is its defining feature. Pallet load can be up to four tonnes when turning at maximum rotational speed of 300rpm. Software is included in the control as standard for actively balancing the loaded table, with monitoring provided by imbalance sensors. B+W builds its tables with a large INA (Schaeffler Group) ZKXDF or ZKLDF angular-contact thrust ball bearing of diameter between 460 and 725mm, depending on machine model. Construction height of the table is low despite the high power, maximising the machining envelope. A different adapter plate is utilised for supporting heavy driven tool heads, such as this NC facing slide, again avoiding unnecessary stress on the spindle bearings Five-channel hydraulic transfer is possible up to maximum rpm. The table motor stator and rotor are actively cooled by a water-glycol mixture to prevent thermal movement. The travelling-column machine design allows the X-axis to be hydraulically clamped by a large brake disc during turning for extra rigidity and machining accuracy. As the X-axis does not move during the turning section of a cycle, motion control is drive-friendly and energy efficient. The table bearing absorbs a high tilting moment up to 45,000Nm. Pallet positioning is to within 10µm, assisted in part by automatic cleaning of its underside and the pallet clamping surface before exchange. Kingsburywww.kingsburyuk.com

Broaching, whether traditional or with CNC indexable tooling, can present challenges. Many are being overcome or at least mitigated with technology or by tweaking the process.