Change comes to tool grinding technology the way it does to other manufacturing technologies: equipment makers listen to their customers’ changing requirements and work with them to develop improvements. We asked developers of tool grinding systems to talk about what their customers expect from the equipment now, why it goes beyond what they might have expected even a few years ago—and how those expectations are being met.
It’s not a surprise that in 2021 there is a lot of interest in automation, Industry 4.0, and technologies used to digitally lash all aspects of production together. As Pat Boland, joint managing director of ANCA Inc., Wixom, Mich., put it, “It’s pretty simple. The customers are after more productivity, higher accuracy, and more process stability.” There are developments in each of those trends, he said.
“What’s new at ANCA is what we call AIMS, or the ANCA Integrated Manufacturing System. It’s the overarching platform under which we’ll be releasing software and hardware though the coming years. At the top is an overarching suite of management software, and underneath is all of the hardware to grind, measure, and process cutting tools.”
More than 70 percent of the company’s customers require machines with robotic functionality, he said. The AIMS system connects all of the processes used in cutting tool manufacturing—the automation, measurement equipment and post-production processes such as laser marking as well as the grinding equipment itself. “The interconnected grinding technology solution eliminates wasteful manual handling, reduces machine downtime between batches and takes away the need to have operators constantly monitoring and adjusting production machines,” he said.
AIMS is designed for modular functionality that can be adapted to each factory’s needs, from smaller-scale, data-based options to a full setup across a series of machines. AIMS delivers a connected tool production process, including:
- transferring tools between operations with an AutoFetch robot,
- fully automating tool measurement and process compensation with AutoComp software module, and
- managing data with the AutoSet hub.
The AIMS Server manages data flows between the elements of the system and established IT platforms, such as an ERP system. Users can choose from a suite of solutions to reduce production costs and integrate systems appropriate to improving their specific processes and product quality.
That ANCA’s solutions embrace not only the grinding process itself but other pieces of the production puzzle as well is demonstrated by the company’s newest equipment release, according to Boland.
“Our newest offering is actually a laser marking system, which fits in with the software suite and also takes tools in a palette directly from the grinding machine,” he said. AutoMarkX is capable of automated pallet loading and takes care of the tool laser marking process, freeing up operators to perform more value-added tasks. AutoMarkX is designed for integration with AIMS, being able to automatically receive and dispatch pallets from AutoFetch, while connectivity to the AIMS Server provides details of the message to be marked on the tools, he noted.
“We’ve had a number of cells where the individual machine has a laser marker integrated with it. And that’s for traceability.” The marking is not only during tool production but also for use in resharpening operations, he explained.
In such cases, the machine reads the existing laser mark and processes the tool based on that mark. And once the tool has been resharpened, the laser mark is updated. For example, “in a structured environment a cutting tool can be resharpened three times,” he said. Before the tool is resharpened, “the system reads the laser marking, which can show that a given tool has been resharpened, say, twice already. And after it’s sharpened again, the mark is updated to show that this was its final time for resharpening.”
Trickier tool geometries
Tool geometries are becoming more sophisticated and challenging according to Rollomatic Inc. President Eric Schwarzenbach. “So, the ability to consistently maintain precise accuracies is paramount. Along with flexibility and precision, the equipment needs to maintain a high level of stability in a production environment,” he said.
The Mundelein, Illinois company’s six-axis GrindSmart 830XW uses both hydrostatic technology and linear motors to produce tools from 1 to 32 mm in diameter with flute lengths of up to 200 mm. The 830XW is “the first and only tool grinder to combine the technologies of hydrostatic guideways and linear motion,” Schwarzenbach said. The hydrostatic guideways practically eliminate friction even with heavy loads because unlike with traditional guideways, “there is no mechanical contact—the weight rides on a highly pressurized film of oil,” he explained. This approach “provides an exceptionally high degree of rigidity and dampens vibrations that naturally occur during grinding,” increasing the life of the grinding wheels and enabling consistently high surface finishes and sharp cutting edges.
The heavy, three-point machine base helps maintain stability, as does the machine’s coolant enclosure, which is kept unconnected to the base, preventing it from transmitting vibrations to the latter, Schwarzenbach noted. Thermal stability is maximized through the use of a single oil for the hydrostatic slides, the cooling of the grinding spindle, and as coolant deployed during grinding.
Throughput is maximized with an integrated 15-station wheel and nozzle changer with speeds of five seconds arbor-to-arbor. The wheel changer is operated by two separate FANUC motors and equipped with a high-speed FANUC robot for extended loader capacity.
Multiplying Micro Tools
Another trend is higher demand for micro tools than in earlier years, Schwarzenbach noted. “The medical, electronics and moldmaking industries are all using more small-sized carbide and HSS [high-speed steel] tools than ever before,” he said.
And that has kept the company’s six-axis GrindSmart Nano6 machine in demand. The system is designed for the production of high-performance micro tools made of carbide or HSS with a diameter range between 0.03 – 2.0 mm. The grinding range starts at 35 µm and goes up to 0.125" (3.18 mm) for end mills and drills. The linear feedback of the hydrostatic axes is by way of linear glass scales with a resolution of 50 nm.
It features a patented, self-adjusting shank guide system and floating workhead bearing assembly that enables concentricity tolerances below 1 µm and also speeds and simplifies setups.
“The shank guide doesn’t require indicating the blank during setup,” he said. “The machine will probe the first blank and the software will grind the geometry out-of-center to the workhead, but in line with the tool axis.”
Designed for production, the Nano6 comes standard with an integrated robot loader that can accommodate up to 1,000 tools. The company’s pick-and-place loader is accurate, reliable and fast, loading/unloading tools in eight seconds, according to Schwarzenbach.
The machine has a FANUC CNC with integrated PC, a 15" (38.1-mm) touch screen and ergonomic control panel. The company’s VirtualGrind Pro programming software comes standard.
Automation for Skilled-Worker Scarcity
Derrick Bailey, applications engineer for tool & cutter grinders at Vollmer of America Corp., Pittsburgh, also highlighted the increase in micro tool use; the company’s five-axis VGrind 340S grinding machine enables the machining of carbide tools in a diameter range between 0.3 and 12.7 mm, he said. The 340S features two vertical spindles for different grinding wheel sets, which makes it possible to reduce non-productive times. The linear axes are non-contact, direct drives.
The options for the VGrind 340S illustrate a major customer trend, Bailey said—the continuing demand for integrated automation.
“The lack of skilled workers has forced many of our customers to look for automation that lets each operator be responsible for a bigger workload and that enables lights-out production,” he said. “This isn’t a new trend, but the challenges of the COVID-19 shutdowns bring it even more to the forefront.”
And while skilled workers are scarcer, the work itself has become more complex.
“Ten years ago I worked in a shop with no automation at all, but the making of many current cutting tools now is a more complicated operation—they require the use of more grinding wheels, with more steps in the process,” he said. “Waiting next to a machine in order to change out a wheel is not the ideal use of a worker’s time—not when automation can do it.”
Automation options on the VGrind 340S include the HP 160 pallet magazine and the HPR 250 free-arm robot, which enable 24/7 unattended machining of up to 900 tools with different shank diameters. The VGrind 340S features a replaceable dressing device for the grinding wheels to achieve optimum concentricity and axial runout for the wheel packages. An optional probe enables grinding wheel calibration in the machine and offers the option of recalibrating the handling mechanism as often as required. A sticking unit enables the abrasive coating to be opened during production. In addition, wheel coolant nozzles can be replaced automatically, as can the wheel packages themselves.
Remote Servicing with Visual Support
The need for toolmakers to continually do more with fewer skilled workers has put pressure on them to minimize machine downtime, Bailey noted. “Particularly for customers who are establishing Industry 4.0-compliant facilities, maximizing quality and throughput is vital,” he said. “They are requiring faster equipment servicing to reduce downtime.”
In response, Vollmer is leveraging technology to offer visual support for its equipment. Encrypted video and audio channels link customers to technicians in real time. Live streaming means that the help desk and onsite team share the same view of the mechanical and electrical areas of a machine. With live streaming, a Vollmer expert can remotely reach the shop floor, look and listen, and provide targeted instructions. The communication is based on the third-party oculavis SHARE service solution, and can be used on mobile devices such as smartphones, tables or even smart glasses.
“The process can be tracked transparently for both parties and multiple participants can be involved if necessary. Since all participants can see the same thing, misunderstandings in communication are reduced, errors are identified quickly and questions are answered more effectively,” Bailey said. “And, relevant to the skilled-worker shortage, it can be used for individual online training sessions as well.”