Stephanie (Monsanty) Hendrixson served as a Modern Machine Shop summer intern in 2012 and joined the team as an assistant editor later that fall. She currently works on event news for MMS Online and on the production of the print magazine. She also blogs about additive technology and helps to manage Additive Manufacturing magazine as its associate editor. Stephanie holds an M.A. in professional writing from the University of Cincinnati and a B.A. in English literature and history from the University of Mount Union.
Read the February digital edition by clicking on the photo above.
The part pictured on the cover of the February 2016 issue is a near-net-shape component of a satellite propellant tank that was made by Lockheed Martin Spacy Systems via Electron Beam Additive Manufacturing (EBAM). This wire-fed process can be used as an alternative to forging, particularly for large or complex metal parts in which it often offers an advantage in lead time. Click the cover image above to access the digital edition of the magazine and turn to page 24 to read the full story.
Also in this issue:
What Renishaw is doing to ease AM integration for manufacturers;
How 3D-printed custom fixturing helps a moldmaker remain flexible to the demands and deadlines of its customers; and
What Delcam learned about additive manufacturing during trial runs producing a 316L stainless steel manifold with a powder-bed process.
DMG MORI opened its Pfronten, Germany, plant to more than 8,000 visitors including journalists and customers for its annual open house January 26-29. Ninety machines were on display spread throughout 4,200 square meters of floor space, including six world premieres:
The CTX Gamma 3000 TC second generation turn-mill, with an extended turning length of 3,050 mm;
The DMU 160 P DuoBlock fourth generation universal milling machine, the largest model in its series with a work envelope measuring 1,600 × 1,600 × 1,100 mm;
The DMU 210 P second generation universal milling machine equipped with an intelligent cooling system to boost precision and long-term accuracy;
The DMU 600 Gantry linear XXL, a gantry-style machining center that can accommodate workpieces weighing as much as 150,000 kg;
The Dixi 125, the smallest in its series of high-precision milling machines designed for workpieces ranging to 1.250 mm in diameter; and
The Ultrasonic 20 linear second generation machining center, equipped with SmartSonic technology to automatically implement the ultrasonic frequency that is best suited to the actuator and tool.
That all these premieres build on past generations speaks to a point brought up during the event. In a press conference, DMG MORI President Dr. Masahiko Mori noted that the company is focused on improving the performance of existing machines, and placing an increased emphasis on streamlining its product line. The company aims to reduce its product offerings from around 300 to about 220 over the next year, with an ultimate goal of reducing that further to 150 or 160 total.
Along with consolidating the lines, the company is also moving toward more standardization, with components that will be interchangeable across products. For instance, a wheel-type toolchanger prevalent on machines throughout the plant is one such component. The modular ATC is a replacement for chain-type magazines and is said to be easy to maintain; one through five wheels can be combined on a single system. Standardized physical components like this simplify machine tool building and assembly, and make it easier to produce and supply spare parts to customers. Combined with the Celos control used across DMG MORI machines, the strategy also supports the implementation of process tracking and data-driven manufacturing.
Dr. Mori and Dr. Rüdiger Kapitza, DMG MORI chairman, also spoke about the company’s recent decision to serve U.S. customers directly rather than through distributors. In order to support this move, DMG MORI will open more technical centers as well as employ more local agents who can act as training and support personnel for customers. By providing a more direct link to users, DMG MORI hopes to provide better solutions to its users and also acquire more direct feedback to help it improve its products.
The press conference included announcements of several new technical centers worldwide, including Moscow, Russia, (opening May 23, 2016) and Seoul, South Korea (opening during the second quarter of 2016).
Mold manufacturer TriPro Technologies prides itself on working closely with customers to prototype and help refine the design of products before building the molds. Its Maker Gear M2 3D printer helps with this service, enabling the shop to quickly turn out prototypes. But the printer is also used in production. 3D-printed custom supports and workholding fixtures have saved the shop money and time in turning around its moldmaking work.
The image above depicts one example. The plastic injection-molded part on the left is a component for a feed auger, used to push product up and out of a chute. The piece was designed to be held in place with two stainless steel rivets pressed into the two holes and attached to the auger via rare earth magnets.
The angle of the holes combined with the curve of the part made it necessary to build the B side of the injection mold in three parts, so that they could be removed without damaging the features. Holding this section of the mold for machining in the shop’s sinker EDM proved to be a challenge; aside from consisting of multiple pieces, this portion of the mold offered no parallel sides for clamping. A custom 3D-printed fixture (visible on the right) held the parts together and provided the necessary straight edges.
3D-printed models like this allow Caterpillar to set up CMM programs and other systems before foundry parts arrive.
A long-term goal of the Additive Manufacturing Group at Caterpillar is to explore how additive technologies like selective laser sintering (SLS) and fused-deposition modeling (FDM) could be applied for the production of end-use components, such as low-volume plastic parts or one-off replacements for legacy equipment. However, it has also found ways of improving current production with additively manufactured gages, assembly fixtures and other manufacturing aids.
The 3D-printed part shown above was created to speed up setup tasks for a production line. The part is a model of a forged track link, a component of the chain-like assembly found on dozers and other track-type equipment. In the past, workers would have used heavy models made from wood when creating fixturing and programming CMMs. Or, they would have waited for the parts themselves to arrive from the foundry. With 3D printing, Caterpillar made 36 ABS polycarbonate models of the track link. The lightweight models were much easier to handle and allowed employees to complete setup more quickly. The company estimates that making this change saved $160,000 in time and labor. Read more about additive manufacturing at Caterpillar.
High-efficiency machining (as opposed to say, high-speed machining) aims to reduce overall cycle time with a more efficient cutting process. This means taking fewer cuts at higher torque and deeper depths—often the full length of the flute—to clear material as efficiently as possible. To compensate for the larger axial depth of cut and avoid overloading the machine or tool, HEM relies on strategies such as a smaller radial depth of cut and different cutting patterns than conventional machining.
The right cutting tool can help, too. At EMO this year, IMCO Carbide introduced two series of tools designed specifically for high-efficiency machining. The Pow-R-Path IPT and IPC series have a larger diameter core to help avoid breakage in continuous cuts as deep as 4.5×D. Both 7- and 9-flute tools are offered. To aid in chip removal, the cutting tools are available with IMCO’s Chip Management System (CMS), which leverages a series of small notches on the cutting edges to break chips into shorter pieces that are easier to remove from the cutting area with coolant or an air blast. When paired with HEM tool paths, the series tools can run at higher feed rates and reduce overall cycle times.
The video above demonstrates how this works, showing a 1/2" IPT7 mill using a HEM strategy compared to a 1/2" four-flute mill using a more conventional method with multiple cutting passes.