Mark Albert is editor-in-chief of Modern Machine Shop Magazine, a position he has held since July 2000. He was associate editor and then executive editor of the magazine in prior years. Mark has been writing about metalworking for more than 30 years. Currently, his favorite topics are lean manufacturing and global competitiveness. Mark’s editorial activities have taken him to numerous countries in Europe and Asia as well as across the United States many times. He is a graduate of the University of Cincinnati (Cincinnati, Ohio) and Indiana University (Bloomington, Indiana).
For multi-axis machining, a good workholding fixture gets the part away from the worktable surface, yet holds the part securely for aggressive machining. This video shows a dovetail pedestal doing this job.
Note the extra “elbow room” the spindle head needs to access five sides of this workpiece. The video is also a good example of 3+2 machining, which is one of the most valuable options for a machine with full five-axis capability. In this case, the machine is a DMG MORI DMU 50 five-axis machining center under power at Boldt Machinery Inc. in Erie, Pennsylvania, for a recent customer demo event highlighting 3+2 machining.
You don’t need to watch the entire video (it’s 10 minutes long). Sampling different segments, however, reveals a variety of operations, mostly with short, stout cutting tools that make 3+2 machining an advantageous option.
What the video does not show is the new triangular geometry incorporated into the dovetail clamping surfaces of this pedestal fixture. You can get that story here. The new fixturing system is from AMT Innovations of Orchard Park, New York.
In addition, examples of using multiple pedestal fixtures to hold large parts can be seen here. Of course, the applications shown are useful for thinking about the flexibility of pedestal workholding fixtures in general.
“The Cylindrical Grinding Universe” was the theme for United Grinding’s 2015 Motion Meeting in Switzerland. This theme was particularly appropriate because a key point was the expansion of ID grinding capability to provide universal coverage of the full range of workpiece sizes.
Every year, United Grinding hosts a gathering of its sales partners and trade press editors from around the world. The purpose of this annual ‘Motion Meeting” in Thun, Switzerland earlier this month, was to highlight the group's latest developments in grinding technology, especially in the area of cylindrical grinding, which includes the Studer, Schaudt and Mikrosa brands. United Grinding also used this occasion to deliver its prestigious Fritz Studer Award for innovative research in machine tool or grinding technology.
Topping the list of new products introduced at the event are the Studer S131 and S151 cylindrical grinding machines, which are built on the innovative S141 cylindrical grinding platform. The S141 platform is distinguished by ID and OD grinding capability enabled by a grinding spindle turret that accommodates as many as four grinding spindles. Both internal and external grinding operations can be completed in one setup to enhance accuracy and reduce non-cut times.
The S131 is smaller than the S141. It has a swing diameter over the table of 250 mm (9.8 inches) and a maximum grinding length of 175 mm (6.9 inches) for ID grinding and 125 mm (4.9 inches) for OD grinding. It accommodates workpieces as long as 300 mm (11.8 inches).
The S131 is a compact ID/OD grinder for smaller work pieces.
For reference, the S141 is available in models for machining workpieces with maximum lengths of 300, 700 or 1,300 mm (11.81, 27.56 or 51.18 inches) and IDs ranging to 250 mm (9.84 inches).
To complete the series, the S151 is larger than the S141. The new S151 features a swing diameter over the table of 550 mm (21.6 inches) and a maximum grinding of length of 400 mm (15.7 inches) for ID work and 150 mm (5.9 inches) for OD work. It accommodates workpieces with a maximum length of 700 mm (27.5 inches).
The S151 grinds workpieces as long as 700 mm (27.5 inches).
Studer’s line of ID/OD grinders now covers the range of shaft diameters and lengths with no gaps for both ID and OD capability for complete grinding in one clamping. In addition, all of the machines share the same ergonomics and clean, streamlined styling of the enclosure and pendant-mounted control unit.
Another recent product worthy of mention is the CrankGrind, a crankshaft grinding machine from Schaudt. Cosmetically, this grinder sports that “new look” that represents the unified corporate identity within the Cylindrical Grinding Group as well as the company-wide emphasis on functionality and ergonomics. More important is its capability. The CrankGrind is designed to do rough- and finish-grinding of both main and pin bearings on automotive crankshafts, all in one setup on one machine.
The Schaudt CrankGrind is designed to be a “superproductive” grinder for the complete grinding of automotive crankshafts.
The Motion Meeting also affirmed Studer’s leadership in energy efficiency, which is a concern among all machine tool builders and end users. Studer’s multi-prong approach may be a model for comprehensive energy management in industrial equipment. For detailed commentary, click here.
A further highlight of the meeting was the presentation of the 2014 Fritz Studer Award to Dr. Eduardo Weingärtner from the Swiss Federal Institute of Technology Zürich. Dr. Weingärtner’s work pioneered the application of the wire EDM process for on-machine dressing of metal bonded grinding wheels. This research was instrumental in the introduction of the Studer WireDress system detailed here.
Finally, as a bonus for visiting trade press editors, a tour of United Grinding's Mägerle brand was arranged in Fehraltdorf prior to the conclave in Thun. Mägerle, part of the company’s surface and profile grinding group, specializes in large, multi-axis grinding machines. These highly engineered systems are custom-built from flexible modules to combine unique applications with proven design concepts. Although Mägerle grinders represent some of the most demanding and advanced applications in grinding, the company continues to rely on a solid foundation of traditional skills such as hand scraping of ways for mechanical accuracy. In fact, the company's apprenticeship program aggressively courts young talent to replenish its highly skilled workforce, and is a model for sustaining the thoroughly Swiss tradition of precision and meticulous craftsmanship.
Although Magerle does not produce “standard” models of grinders, it does offer distinct product ranges, including the MFP line of multi-axis surface and profile grinders. The MFP 50 shown here is part of a grinding cell for a jet engine manufacturer. The new styling of the MFP grinders reflects the corporate redesign.
Torque motors are commonly used in indexing tables on machine tools. This succinct article helps you evaluate this and other applications in which power transmission for rotation calls for the advantages of a torque motor.
Torque motors simplify integration, offer high performance, reduce the cost of ownership and have an extensive working range.
The article was composed by Brian Zlotorzycki, a product specialist at ETEL, a Swiss designer and producer of components for direct drive technology. ETEL is part of Heidenhain, a supplier of machine tool CNCs, encoders, touch probes and other products for precise motion control and measurement.
Data embedded in a 3D model will serve as a “digital thread” that unifies and integrates all manufacturing steps to save time and cut costs.
The National Institute of Standards and Technology (NIST) is initiating a project to demonstrate how a standardized 3D model of a product can integrate and streamline production from initial design through final inspection in a continuous, coherent data-driven process. With this project, NIST researchers and their industrial partners intended to develop what they see as a new dimension to manufacturing capabilities.
The project will demonstrate the feasibility—and benchmark the advantages—of using standardized, 3D models for electronically exchanging and processing product and manufacturing information all the way from design through inspection of the final part. This tightly integrated, seamless string of activities is what manufacturers are calling a “digital thread.” The project is aptly named the Design to Manufacturing and Inspection Project.
This approach contrasts with the common practice of converting 2D computer-aided design (CAD) drawings into static documents. The 3D models will be embedded with data and instructions that computers can interpret and apply to key manufacturing functions. According to NIST, this development will open the way to significant operational and bottom-line benefits. These include reduced cycle time and cost, less duplication of effort, lower risk of errors, increased part yields and higher-quality products.
Collaborators in the NIST-led project include International TechneGroup Incorporated (ITI), Milford, Ohio, and Advanced Collaboration Consulting Resources, Summerville, South Carolina, who are interoperability-focused manufacturing-services providers. Also participating are Rockwell Collins, an Iowa-based manufacturer of avionics and communication equipment for defense and commercial uses; and Geater Machining and Manufacturing, an aerospace supplier located in Independence, Iowa. Other participants are CNC Software, a Tolland, Connecticut, maker of computer-aided manufacturing (CAM) software; Mitutoyo America, a maker of measurement equipment and software; and software vendor CoreTechnologie, Rossford, Ohio.
The apparent catalyst for integrating this project is a new international standard for incorporating computer-readable product and manufacturing information (PMI) into 3D models. These models do not require human interpretation of graphical depictions followed by manual data reentry. Recently published by the international Organization for Standardization, ISO 10303-242 (also known as STEP AP 242) enables designers and process and systems engineers to embed 3D representations of parts with actionable specifications for materials, geometrical and dimensional tolerances, and surface texture, as well as process notes, finish requirements and other information
In the new project, Rockwell Collins will use its CAD system to generate a 3D design of a part, complete with all feature tolerances and other specifications. The design will be translated into STEP AP 242 so that Geater Machine and Manufacturing can repurpose the model into the language understood by the software it uses to generate machining instructions. Independently, Geater will reuse the STEP AP 242 model in software to generate code that will direct a coordinate measuring machine (CMM) to determine whether the part is manufactured as designed. The intent is to perform this step with no manual data entry. The project calls for researchers to verify and validate translations involved in the data exchanges at each stage in this thread.
The project will promote the implementation of data-driven manufacturing. “The various systems involved need to be autonomous, self-aware and self-correcting,” says NIST systems analyst Allison Barnard Feeney, leader of the project. “At the same time, they must be able to work harmoniously with human supervision and collaboration."
A full-scale demonstration of end-to-end interoperability is expected by summer 2015.
PMTS 2015 has more than 270 exhibitors displaying the latest in precision machining technology and showcasing ideas on how to improve processes and increase profits. Networking opportunities and other intangible benefits also set this show apart.
PMTS is presented by the Precision Machined Products Association (PMPA) and co-presented by Production Machining and Modern Machine Shop. PMTS is the precision machining industry’s signature event, offering the largest on-site gathering of precision machining equipment.