Precision grinding is evolving incrementally

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1 The recently renamed Helitronic Vision 700 L from Walter specializes in long milling cutters, drills, step drills, woodworking tools and profiling tools from 3 to 200 mm in diameter. Grinding Toward Perfection Multiaxis grinding machines get creative with their axes, moveable workholding systems, software and measuring tools Sarah A. Webster Editor in Chief Precision grinding is evolving incrementally to better handle old challenges and new. These include manufacturing, regrinding and finishing tools and eccentric parts such as nonround or nonpolygon shapes made of a wide range of materials. To meet these challenges, a variety of machine builders are offering faster, more accurate multiaxis precision grinding machines. Many come with other new enhancements such as improved in-process gaging, systems that easily or automatically dress, change and balance a growing number of wheels and even new mechanical approaches that promise to reduce machine wear and maintenance or move the workpiece in creative ways. November 2013 ManufacturingEngineeringMedia.com 89

2 And that doesn t even include the changes in software, which are moving toward working (almost) automatically with accessories to deliver a near-perfect part with little operator involvement. ALTERA MULTI-SENSOR CERAMIC CMM Nikon Metrology is the only manufacturer to guarantee the original accuracy of its CMMs for 10 years.* Nikon Metrology s range of premium quality CERAMIC CMM s have been refined to meet the varying needs of manufacturers. The superior design, with near perfect stiffness-to-weight ratio and greater resistance to temperature shifts, provides consistent and long-lasting performance across all manufacturing environments. Advanced multi-sensor technology optimizes CMM throughput and broadens the application scope to new materials and components. Ideal for use in the automotive, aerospace, & medical device industries and in almost all job shop applications! NIKON METROLOGY, INC. T E Marketing.nm-us@nikon.com SEE US AT QUALITY EXPO, BOOTH # 408, CHICAGO, IL, SEPT AND AT WESTEC, BOOTH #2606, LOS ANGELES, CA, OCTOBER NIKON METROLOGY I VISION BEYOND PRECISION For more information: Combining Grinding and Erosion One shift that has had a big impact on grinding is the increasing use of new materials, such as carbon fiber reinforced plastics (CFRPs) and other composites, in industries such as aerospace and automotive. That, in turn, is driving an increase in demand for tools made out of super-hard materials. Tools made out of polycrystalline diamond (PCD), the hardest man-made material in the world, are targeted for the machining of nonferrous materials, such as CFRPs, aluminum, titanium alloys, ceramics and carbides. Meanwhile, polycrystalline cubic boron nitride (PCBN), the second hardest material, is targeted for cutting iron-based alloys, such as cast irons, hard steels and ironbased composites. Making these superhard tools is a challenge that is leading the development of new approaches. Take the new Anca EDGe, launched at EMO Hannover 2013 in September. The EDGe machine features a doubleended wheel spindle that has the ability to both erode PCD and grind carbide and high-speed steel (HSS). The ability to manufacture a variety of tools (up to 220 mm in diameter and up to 20 kg in weight) makes the EDGe ideal for customers looking to reduce the risk associated with moving into the growing PCD side of the business. While erosion-grinding machines aren t new in and of themselves, the double-ended HSK wheel spindle in the EDGe can erode and grind in one setup and it has other new features as well. Russell Riddiford, president, Anca Inc. (Wixom, MI) said the proprietary EDGe-Spark generator monitors and controls the energy level of every spark for the resistivity of the substrate, be it tungsten carbide, diamond or cobalt binder. It automatically detects the substrate and adaptively adjusts the gap NEW * Conditions apply, see Nikon Metrology website for full details Excellence now and in the future See us at FABTECH Booth #S ManufacturingEngineeringMedia.com November 2013

3 distance for optimum surface finish, material removal and cycle time. What s more, it provides exceptional operator feedback in real time. We take the precision and high-accuracy demands of our customers very seriously, Riddiford said. Testing of tools eroded on the EDGe machine resulted in better figures for cutting force, exit burrs on CFRP and drill life than ground tools, Anca said. The process achieves surface finish on tools of less than 0.2 µm R a. Anca, an established grinding company that is well known for its ToolRoom design software, also boasts that the EDGe has a fast, easy-to-use interface for inputting tool geometry. The Anca software, which includes integrated 3D graphics, is used to adjust power generator settings and is designed to create programs for a wide range of tool types. In order to deliver the EDGe, Anca partnered with Precorp, a leading manufacturer of PCD cutting tools and a key supplier to companies such as Boeing, as well as the Royal Melbourne Institute of Technology, which assisted the project with research and data analysis. The EDGe, with a base made of polymer concrete, weighs 4500 kg and is 2160-mm wide, 1530-mm deep and 1990-mm high. It accommodates wheel sizes up to 202 mm. The machine offers programming resolution down to mm in the X, Y and Z axes, with programming down to in the C and A axes. The standard in-process probe system is from Renishaw. A Solution for Very Long Tools Meanwhile, the Walter brand from United Grinding (Miamisburg, OH) has developed a unique approach to grinding long, rotationally symmetrical tools up to 700 mm in length made of carbide, HSS, ceramic, cermet and cubic boron nitride (CBN). Walter sees a market in the automotive sector, which is replacing many gundrill and deep-hole indexable applications with very long solid-shank drills for engine blocks and crank housings. Spiral-flute tools offer faster feed rates, due to their higher chip removal rates. Originally introduced in 2012 as the Helitronic Vision Long, the recently renamed Helitronic Vision 700 L from Walter specializes in long milling cutters, drills, step drills, woodworking tools and profiling tools from 3 to 200 mm in diameter. Visit for a related article, Precision Grinding Strengthens Its Bond with A&D. Not only the cutting surface itself but also how it adheres to a matrix have improved in recent years. The five-axis CNC Vision 700 L is based on the popular high-precision Helitronic Vision, which has linear or torque motors in all axes, and a unique kinematics concept. In the Vision, a closed 3D gantry supports the grinding spindle and a large rotary C axis supports the tool, which allows grinding in all four quadrants. But the Vision 700 L features a much larger working envelope than the Vision. The GrindSmart 628XS is a six-axis CNC super precision tool grinder for the manufacturing and regrinding of round & nonround cutting tools, from Ø 0.1 to 16 mm. Its features include an automatic loading/unloading system, precision clamping system, and innovative V-block and steadyrest support. Edward Sinkora, senior product manager for United Grinding s Tool Division, said that finite element analysis showed that we could open up the back of the gantry and reconfigure several parts, including the automated worktable, grinding head and wheel changer to accommodate longer tool lengths. Sinkora said the Vision 700 L does everything the regular Vision does but in order to grind very long tools, we moved the rotary C axis to the grinding head. So in this approach the tool is carried on a strictly linear axis while the grinding spindle swivels. And by opening up the rear of the gantry, the machine is able to travel farther on the X axis during very long grinds. Two independent carriages support the workpiece and allow it to be moved in a manner that allows for graceful grinding down the length of the tool, as shown in a video at tinyurl.com/visionlong. As with the Vision, the machine base of polymer or mineral cast, with the patented gantry, promises extreme rigidity. The maximum control resolution for the linear axes is mm (0.1 µm) and for the rotary axes, º. The 92 ManufacturingEngineeringMedia.com November 2013

4 QVI SNAP Simple, one-button measurement lets you measure entire parts instantly - with no fixturing. Precision Grinding spindle power is 35 kw with 10,000 rpm. Grinding wheels up to a maximum diamater of 254 mm can be changed by means of a 6-, 12- or 24-station wheel changer, with the latter two being options. A Fanuc six-axis CNC robot is used for the automatic loading and unloading of the tools. Two independent carriages support the workpiece and allow it to be moved in a manner that allows for graceful grinding down the length of the tool. Measurements Made Simple. Designers & Manufacturers of Drilling & Tapping Solutions New Slant Bed Precision Tapper offers: Made in USA Always was and Always will be! Proven solutions from the brands you trust Lonergan Drive, Rockford, IL / Fax: 815/ Custom Engineered To Your Needs High speed - High volume Versatile tapping, drilling and reaming Wide range of standard options... Horizontal or vertical configurations also available Flexible parameters (feed & speed) Single or multiple head applications Custom bowl with track & feed fixturing Servo precision control Ball screw drive See this machine and others in action in our new video UNIVERSAL - AUTOMATIC 304 Winston Creek Parkway, Lakeland, FL / Fax: 863/ The Vision 700 L uses Helitronic Tool Studio, Version 2.0, grinding software with complete 3D simulation for secure off-line setup. Tool accuracy can be even further enhanced and certified with the addition of a Helicheck Pro measuring machine, which uses several CCD cameras and segmented LED lights to measure virtually all geometries. Repeatability is under a micron. An optional 1000 magnification camera measures the edge prep (hone) down to a 5-µm radius. For form tools, the software can compare the measured tool profile to the nominal profile and calculate the necessary offsets for the grinder to make the tool, as Sinkora said, more or less perfect. At least under 2 µm. Increasing Flexibility In making continual improvements to its GrindSmart lineup (528XS- 6000XL), Rollomatic (Mundelein, IL) has redesigned its GrindSmart 620XS to make it even more flexible and reliable. The resulting GrindSmart 628XS is a six-axis CNC super-precision tool 94 ManufacturingEngineeringMedia.com

5 grinder for the manufacturing and regrinding of round and nonround cutting tools, from Ø 0.1 to 16 mm. Its features include an automatic loading/unloading system, precision clamping system, and innovative V-block and steadyrest support. The machine can grind specialty tools, including form tools, indexable and nonindexable inserts, replaceabletip tools, reamers, taps, step tools, torx drivers, surgical and dental tools, among others. Aside from improved ergonomics, such as a larger control monitor, the 628XS features a new Fanuc control 30iB. The workhead has been redesigned to accommodate quick-change features to switch from round tools to inserts. The guiderails of the three major linear axes have also been reinforced. The linear scales are not glass scales anymore, but magnetic, which increases the life of the scales, said Eric Schwarzenbach, president of Rollomatic. The design of the guiderails and other moving parts has been deliberately focused on longevity with minimal maintenance intervention. OMG, EXPANDING MACHINE VERSATILITY FOR OVER 50 YEARS We can avail ourselves of the technical know-how and human resources required to design and manufacture cutting edge products. We have a strong focus on providing quality customer service, with the goal of maximizing customer satisfaction. OMG NORTH AMERICA 802 Clearwater Loop, Post Falls, ID Phone: info@omgamerica.com Tilting angle head Series BAH Series MO Series HT Series TSI/TSXTSX Series MT-TC-TC3 Series TA Series VH Series T Previously, the machine featured a belt drive, with a servomotor controlled by a rotary encoder. On the 628XS, we have fitted a rotary glass scale that is directly coupled to the workhead spindle, thereby taking the belt drive out of the equation. This allows us to control the rotary tool axis movement much tighter. Its benefits include better flute finish and higher feed rates. The flexibility of the 628XS lies in several areas. The workhead is configured so one can switch from round tools to inserts simply by swapping two plates. The switch over is remarkably rapid, Schwarzenbach said. The other is the proprietary software, VirtualGrindPro, which features a large library of different types of cutting tools and inserts ready for grinding. The machine also has an optional wheel and nozzle changer, which includes six wheel packs with the coolant nozzles prepared and ready for production grinding. Unique Hydrostatic Guideways While it is marketed as a universal, high-precision grinder, the recently updated Kellenberger Kel-Varia from Hardinge (Elmira, NY) is targeted at low-volume, highvalue, large and heavy parts, especially those that are nonround, such as polygons, free contours, and eccentric shapes a consequence of the C-axis option of interpolating the X and C axes. This spring, Hardinge began offering a new direct-drive workhead and hydrostatic B axis on the Kel-Varia. The precision hydrostatic guideways in combination with the directdrive workhead technology provide extreme accuracy in concentricity and radial run-out: Part roundness of <0.2 μm; nonround contour accuracy of <6 μm; internal eccentric bore of <4 μm; straightness (slots) of <2 μm. Jeff Hilliard, North American sales manager for Grinding, Hardinge, said the hydrostatic guideway system is unique. Hydrostatic guideways, combined with a strict separation of the machine base from the assemblies that generate heat or vibration, provide superb precision and productivity. The hydrostatic guides for the longitudinal slide movement (Z axis) and for wheelslide infeed (X axis) provide the basis for the machine s extreme accuracy. The X- and Z-axes movements are practically frictionless at all speeds. There is no stick slip; even the smallest increments of 0.1 μm can be traveled without a problem. Because there s no metal-to-metal contact, there are also no wear characteristics compared to the traditional Vee and Flat system. 96 ManufacturingEngineeringMedia.com November 2013

6 There s a film of oil for shock absorption, Hillard explains. kg). Previously, these bigger molds would have endured days You don t have to worry about bearings and guideways upon days of finish polishing, Hillard said. But now, We can being damaged. eliminate a lot of steps and tons of man hours of hand-polishing the mating parts. ME The direct-drive workhead has an infinitely variable spindle speed from 1 to 500 rpm (with Heidenhain control) with a maximum weight capacity of 750 Nm / 300 kg (660 lbs) with an option of ±60 second micro-correction for easy adjustment of cylindricity. The new workhead allows heavy parts to be quickly and precisely THE HOT RODS OF CUTOFF LATHES accelerated and braked with zero backlash during bidirectional movements for increased productivity. A Follow us on large spectrum of parts and a wide range of geometries can be processed using combinations of cylindrical Type in MMTco grinding, OD and ID out-of-round grinding, thread grinding and jig grinding all in one setup. Advanced C-axis (ultra-high resolution) operation allows precise grinding of grooves and FEATURES: satellite and centering bores. Two Axis Slide Hardinge finds many of the end High Torque Digital Drive users of the Kellenberger Kel-Varia are Menu Prompted Touch Screen Digital Read Out or Servo Positioned in the container mold business. The Heavy Duty Stock Stops Kel-Varia can now deliver parts up to 24" (610 mm) in diameter. Previously, 18" (457 mm) was the limit. The weight limit also has doubled to 550 lb (250 Cut to the Finish Want More Information? Anca Inc. Ph: Web site: Hardinge Inc. Ph: Web site: Rollomatic Ph: Web site: United Grinding Technologies Ph: Web site: Modern Machine Tool has been building cutoff lathe machines for almost a century. Our lathes have evolved over the years into a completely automatic operation from feeding to cutting to finishing. Our compact cast iron slide unit offers rigidity with the speed and serviceability of linear technology. The precision ground, ball-screw driven slides with high torque digital drives provide easy set up and increased tool life. An optional two axis servo slide is available for simple turning, boring and drilling operations. These systems can handle material.25 to 8. Call us today and find out how speed and precision have become one Losey Avenue Jackson, MI ModernMachineTool.com November 2013 ManufacturingEngineeringMedia.com 97