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hyperMILL 2024 CAD/CAM software suite

OPEN MIND Technologies has introduced its latest hyperMILL 2024 CAD/CAM software suite, which includes a range of powerful enhancements to its core toolpath capabilities, as well as new functionality for increased NC programming efficiency in applications ranging from 2.5D machining to 5-axis milling. New and enhanced capabilities include: Optimized Deep Hole Drilling, a new algorithm for 3- and 5-axis Rest Machining, an enhanced path layout for the 3D Plane Machining cycle, better error detection, and much more.
Learn more.

One-part epoxy changes from red to clear under UV

Master Bond UV15RCL is a low-viscosity, cationic-type UV-curing system with a special color-changing feature. The red material changes to clear once exposed to UV light, indicating that there is UV light access across the adhesive material. Although this change in color from red to clear does not indicate a full cure, it does confirm that the UV light has reached the polymer. This epoxy is an excellent electrical insulator. UV15RCL adheres well to metals, glass, ceramics, and many plastics, including acrylics and polycarbonates.
Learn more.

SPIROL Press-N-Lok™ Pin for plastic housings

The Press-N-Lok™ Pin was designed to permanently retain two plastic components to each other. As the pin is inserted, the plastic backfills into the area around the two opposing barbs, resulting in maximum retention. Assembly time is quicker, and it requires lower assembly equipment costs compared to screws and adhesives -- just Press-N-Lok™!
Learn more about the new Press-N-Lok™ Pin.

Why hybrid bearings are becoming the new industry standard

A combination of steel outer and inner rings with ceramic balls or rollers is giving hybrid bearings unique properties, making them suitable for use in a wide range of modern applications. SKF hybrid bearings make use of silicon nitride (twice as hard as bearing steel) rolling elements and are available as ball bearings, cylindrical roller bearings, and in custom designs. From electric erosion prevention to friction reduction and extended maintenance intervals, learn all about next-gen hybrid bearings.
Read the SKF technical article.

3M and Ansys train engineers on simulating adhesives

Ansys and 3M have created an advanced simulation training program enabling engineers to enhance the design and sustainability of their products when using tapes and adhesives as part of the design. Simulation enables engineers to validate engineering decisions when analyzing advanced polymeric materials -- especially when bonding components made of different materials. Understand the behavior of adhesives under real-world conditions for accurate modeling and design.
Read this informative Ansys blog.

New FATH T-slotted rail components in black from AutomationDirect

Automation-Direct has added a wide assortment of black-colored FATH T-slotted hardware components to match their SureFrame black anodized T-slotted rails, including: cube connectors (2D and 3D) and angle connectors, joining plates of many types, brackets, and pivot joints. Also included are foot consoles, linear bearings in silver and black, cam lever brakes, and L-handle brakes. FATH T-slotted hardware components are easy to install, allow for numerous T-slotted structure configurations, and have a 1-year warranty against defects.
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Weird stuff: Moon dust simulant for 3D printing

Crafted from a lunar regolith simulant, Basalt Moon Dust Filamet™ (not a typo) available from The Virtual Foundry closely mirrors the makeup of lunar regolith found in mare regions of the Moon. It enables users with standard fused filament fabrication (FFF) 3D printers to print with unparalleled realism. Try out your ideas before you go for that big space contract, or help your kid get an A on that special science project.
Learn more.

Break the mold with custom injection molding by Rogan

With 90 years of industry experience, Rogan Corporation possesses the expertise to deliver custom injection molding solutions that set businesses apart. As a low-cost, high-volume solution, injection molding is the most widely used plastics manufacturing process. Rogan processes include single-shot, two-shot, overmolding, and assembly. Elevate your parts with secondary operations: drilling and tapping, hot stamping, special finishes, punch press, gluing, painting, and more.
Learn more.

World's first current-carrying fastening technology

PEM^® eConnect™ current-carrying pins from Penn-Engineering provide superior electrical connections in applications that demand high performance from internal components, such as automotive electronics. This first-to-market tech provides repeatable, consistent electrical joints and superior installation unmatched by traditional fastening methods. Features include quick and secure automated installation, no hot spots or poor conductivity, and captivation options that include self-clinching and broaching styles.
Learn more about eConnect pins.

New interactive digital catalog from EXAIR

EXAIR's latest catalog offers readers an incredible source of innovative solutions for common industrial problems like conveying, cooling, cleaning, blowoff, drying, coating, and static buildup. This fully digital and interactive version of Catalog 35 is designed for easy browsing and added accessibility. Customers can view, download, print, and save either the full catalog or specific pages and sections. EXAIR products are designed to conserve compressed air and increase personnel safety in the process. Loaded with useful information.
Check out EXAIR's online catalog.

5 cost-saving design tips for CNC machining

Make sure your parts meet expectations the first time around. Xometry's director of application engineering, Greg Paulsen, presents five expert tips for cutting costs when designing custom CNC machined parts. This video covers corners and radii, designing for deep pockets, thread depths, thin walls, and more. Always excellent info from Paulsen at Xometry.
View the video.

What can you secure with a retaining ring? 20 examples

From the watch dial on your wrist to a wind turbine, no application is too small or too big for a Smalley retaining ring to secure. Light to heavy-duty loads? Carbon steel to exotic materials? No problem. See how retaining rings are used in slip clutches, bike locks, hip replacements, and even the Louvre Pyramid.
See the Smalley design applications.

Load fasteners with integrated RFID

A crane, rope, or chain may be required when something needs lifting -- plus anchoring points on the load. JW Winco offers a wide range of solutions to fasten the load securely, including: lifting eye bolts and rings (with or without rotation), eye rings with ball bearings, threaded lifting pins, shackles, lifting points for welding, and more. Some, such as the GN 581 Safety Swivel Lifting Eye Bolts, even have integrated RFID tags to clearly identify specific lifting points during wear and safety inspections and manage them digitally and without system interruption.
Learn more.

Couplings solve misalignments more precisely with targeted center designs

ALS Couplings from Miki Pulley feature a simplistic, three-piece construction and are available in three different types for more precisely handling parallel, angular, or axial misalignment applications. The key feature of this coupling design is its center element. Each of the three models has a center member that has a unique and durable material and shape. Also called a "spider," the center is designed to address and resolve the type of misalignment targeted. Ideal for unidirectional continuous movement or rapid bidirectional motion.
Learn more.

What is 3D-MID? Molded parts with integrated electronics from HARTING

3D-MID (three-dimensional mechatronic integrated devices) technology combines electronic and mechanical functionalities into a single, 3D component. It replaces the traditional printed circuit board and opens up many new opportunities. It takes injection-molded parts and uses laser-direct structuring to etch areas of conductor structures, which are filled with a copper plating process to create very precise electronic circuits. HARTING, the technology's developer, says it's "Like a PCB, but 3D." Tons of possibilities.
View the video.

Thin explosive films provide snapshot of how detonations start

An image from a test detonation at Sandia National Lab of a thin explosive film, about as thick as a few pieces of notebook paper, with a 3/8-in.-tall thunderbird-shaped barrier. The "shimmering" lines to the right of the thunderbird are the shock waves from the explosion detected by schlieren imaging, a technique that can detect differences in air density. [Photo courtesy of Eric Forrest]

 

 

 

 

Using thin films -- no more than a few pieces of notebook paper thick -- of a common explosive chemical, researchers from Sandia National Laboratories studied how small-scale explosions start and grow. Sandia is the only lab in the United States that can make such detonatable thin films.

These experiments advanced fundamental knowledge of detonations. The data were also used to improve a Sandia-developed computer-modeling program used by universities, private companies, and the Department of Defense to simulate how large-scale detonations initiate and propagate.

"It's neat. We're really pushing the limits on the scale at which you can detonate and what you can do with explosives in terms of changing various properties," said Eric Forrest, the lead researcher on the project. "Traditional explosives theory says that you shouldn't be able to detonate at these length scales, but we've been able to demonstrate that, in fact, you can."

Forrest and the rest of the research team shared their work studying the characteristics of these thin films and the explosions they produce in two recently published papers in ACS Applied Materials and Interfaces and Propellants, Explosives, Pyrotechnics.

For their studies, the team used PETN, also known as pentaerythritol tetranitrate, which is a bit more powerful than TNT, pound for pound. It is commonly used by the mining industry and by the military.

Typically, PETN is pressed into cylinders or pellets for use. The research team instead used a method called physical vapor deposition -- also used to make second-generation solar panels and to coat some jewelry -- to "grow" thin films of PETN.

Sandia is the only lab in the United States that has the skills and equipment to use this technique to make thin explosive films that can detonate, said Rob Knepper, a Sandia explosives expert involved in the project.

Growing and studying thin explosive films
Starting in late 2015, the team grew thin films of PETN on different types of surfaces to determine how that would affect the films' characteristics. They started with pieces of silicon about the size of a pinkie nail and grew films that were about one-tenth the thickness of a piece of paper, too thin to explode. Some of the silicon pieces were very clean, some were moderately clean, and some were straight-out-of-the-box and thus had a very thin layer of dirt -- 50,000 times thinner than a sheet of paper.

On the very clean silicon surfaces, the PETN films formed what appeared to be smooth plates by scanning-electron microscopy, yet had tiny cracks in between plates, somewhat like dried mud on a dried lakebed. On the dirty silicon surfaces, the surface of the PETN films appeared more like even hills.

Using an X-ray-based technique, the researchers determined this is because the PETN molecules orient themselves differently on dirty surfaces compared to very clean surfaces, and thus the film grows differently, Forrest said.

"This study in particular has shown that we can get not just novel, but very useful forms of traditional explosives that you would never be able to achieve via traditional means," Forrest said. "Finely controlling the film properties enables us to investigate theories to better understand explosive initiation, which will allow us to better predict reliability, performance, and safety of explosive systems through improved models."

Knepper, who served as Forrest's mentor on the project, agreed. "Developing a way that we can reproducibly control the microstructure of the films, just through the surface manipulation, is important. Right now, our focus is on using these films to further our understanding of explosive properties at small scales, such as the initiation and failure of explosives."

Small-scale tests to improve computer models
Once the characteristics and properties of the thin films were better understood, the research team grew thicker films -- this time about the thickness of two sheets of notebook paper -- on very clean pieces of plastic about the size of a pinkie finger.

Then, with a bang, they detonated the explosive films inside a specially designed safety enclosure called a "boombox," which was engineered to prevent a detonation from starting while the enclosure was open and to contain any debris from the detonation. Using an ultra-high-speed camera that can take up to a billion frames a second, they watched the shock wave rise up as the explosion raced across the thin film.

Video: The detonation of thin explosive films by Sandia National Laboratories researchers.

In collaboration with New Mexico Institute of Mining and Technology in Socorro, the research team developed a specialized setup to see the shock wave despite the smoke and debris from the test explosions using schlieren imaging, a technique that can detect differences in air density similar to the shimmering over a hot highway.

A mechanical engineering master's student from New Mexico Tech, Julio Peguero, used the data from these experiments to refine Sandia's explosives computer-modeling program. The program, called CTH, can be used for applications, such as to determine how to best shape explosive charges while drilling for oil, Knepper said.

Peguero plotted the velocity of the shock waves above the films with and without gaps and adapted the computer program to better match their experimental results on very thin films. The team engineered thin films with cracks in the middle of various sizes -- ranging from one-third the width of a human hair to 1 1/3 the width of a hair -- to better understand the reliability of thin films and how detonations can fail. The team found that gaps around the size of a hair could stop a detonation from continuing.

Forrest was particularly interested in the gap studies because the first study found thin cracks between the very smooth plates of some of the films. Although these cracks were far smaller than even one-tenth a hair's width, the data from the gap study provided insights into how these films would perform.

Peguero, who is now a Sandia employee, started working on the project in January 2018, first as a student and then later as a Sandia intern. "In addition to the excitement of doing explosives research, I gained an appreciation for measurement uncertainty and risks," Peguero said. "That is especially important for national security work to ensure that our confidence in our measurements is well understood."

Knepper agreed about the importance of the project. He said, "When you have experimental data at small scales, especially those that are relevant for the border between what can detonate and what can't, those data can be really helpful in calibrating computer models. Also, being able to have good characterization of the explosive microstructure to go into the models helps with having parameters that can successfully predict performance over a wider range of explosive behaviors."

Source: Sandia

Published April 2021

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