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.
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.
A while back, a discussion sprang up on our Top Shops LinkedIn group about how to prevent cutting tool injuries. The original poster was looking specifically for ways to protect machinists from getting cut on their hands and arms while working inside CNC lathes. Some great ideas came out of this conversation (in fact, you can still participate at the link above—you’ll need to join the group and be approved if you’re not already a member).
Oddly enough, it was around this time that I visited Swiss Automation, a turning shop that came up with its own solution to this same problem, using an inexpensive desktop 3D printer. Get the whole story on the Additive Manufacturing website.
Hosted by CompositesWorld, the conference examines the expanding role of carbon fiber in the composites industry.
Working with composite parts is a tricky business, because a composite by definition is a combination of more than one material. The properties of any given part depend on a range of factors including how layers are oriented as well as the matrix and reinforcement materials used. Carbon fiber is among the most common reinforcement materials used in composites—which is one of the reasons why our sister publication, CompositesWorld, is hosting a conference devoted to understanding the properties, benefits and applications of this material.