October 15, 2019 Volume 15 Issue 39

Mechanical News & Products

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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.
Learn more.


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.


Particles emitted by consumer 3D printers could hurt indoor air quality

Consumer-grade 3D printers have grown in popularity in recent years, but the particles emitted from such devices can negatively impact indoor air quality and have the potential to harm respiratory health, according to a study from researchers at the Georgia Institute of Technology and UL Chemical Safety.

For the study, which was published September 12 in the journal Environmental Science & Technology and sponsored by Underwriters Laboratories, Inc. (UL)., the researchers collected particles emitted from 3D printers and conducted several tests to gauge their impact on respiratory cell cultures.

Rodney Weber, a professor in Georgia Tech's School of Earth & Atmospheric Sciences, stands in his lab alongside several consumer-grade 3D printers. [Credit: Allison Carter]

 

 

 

 

"All of these tests, which were done at high doses, showed that there is a toxic response to the particles from various types of filaments used by these 3D printers," said Rodney Weber, a professor in Georgia Tech's School of Earth & Atmospheric Sciences, who led the research.

The study was part of a multi-year research project aimed at characterizing particle emissions by the printers in a controlled environment and identifying measures that could be taken by both 3D-printer manufacturers and users to reduce the potential for harm. While earlier studies had focused on quantifying the particles being emitted, this time the researchers looked more closely at the chemical composition of the particles and their potential for toxicity.

3D printers typically work by melting plastic filaments and then depositing the melt layer upon layer to form an object. Heating the plastic to melt it releases volatile compounds, some of which form ultrafine particles that are emitted into the air near the printer and the object.

In earlier research, the team found that generally the hotter the temperature required to melt the filament, the more emissions were produced. As a result, acrylonitrile butadiene styrene (ABS) plastic filaments, which require a higher temperature to melt, produced more emissions than filaments made of polylactic acid (PLA), which melt at a lower temperature.

To test the impact of the emissions on live cells, the researchers partnered with Weizmann Institute of Science in Israel, which exposed human respiratory cells and rat immune system cells to concentrations of the particles from the printers. They found that both ABS and PLA particles negatively impacted cell viability, with the latter prompting a more toxic response. But these tests did not reflect actual exposures

The researchers also performed a chemical analysis of particles to gain further insight into their toxicity and allow comparisons to toxicity of particles found in outdoor urban environments. The analysis -- called oxidative potential -- simulates the toxic response that an aerosol would have on cellular organisms.

"The toxicity tests showed that PLA particles were more toxic than the ABS particles on a per-particle comparison. But because the printers emitted so much more of the ABS, it's the ABS emissions that end up being more of the concern," Weber said. "Taken together, these tests indicate that exposure to these filament particles could, over time, be as toxic as the air in an urban environment polluted with vehicular or other emissions."

Another finding of the study was that the ABS particles emitted from the 3D printers had chemical characteristics that were different than the ABS filament.

"When the filament companies manufacture a certain type of filament, they may add small mass percentages of other compounds to achieve certain characteristics, but they mostly do not disclose what those additives are," Weber said. "Because these additives seem to affect the amount of emissions for ABS, and there can be great variability in the type and amount of additives added to ABS, a consumer may buy a certain ABS filament, and it could produce far more emissions than one from a different vendor."

The study also looked at which types of indoor environmental scenarios emissions from a 3D printer would most impact. They estimated that in a commercial building setting such as a school or an office, better ventilation would limit the amount of exposure to the emissions. However, in a typical residential setting with less effective ventilation, the exposure could be much higher, they reported.

"These studies show that particle and chemical emissions from 3D printers can result in unintentional pollutant exposure hazards, and we are pleased to share this research so that steps can be taken to reduce health risks," said Marilyn Black, senior technical advisor for UL.

In the meantime, some measures can be taken by operators of 3D printers to lessen their impact on air quality:

  • Operating 3D printers only in well-ventilated areas;
  • Setting the nozzle temperature at the lower end of the suggested temperature range for filament materials;
  • Standing away from operating machines; and
  • Using machines and filaments that have been tested and verified to have low emissions.

CITATION: Qian Zhang, Michal Pardo, Yinon Rudich, Ifat Kaplan-Ashiri, Jenny P.S. Wong, Aika Y. Davis, Marilyn S. Black and Rodney J. Weber, "Chemical Composition and Toxicity of Particles Emitted from a Consumer-Level 3D Printer Using Various Materials," (Environmental Science & Technology, September 2019).

Source: Georgia Tech

Published October 2019

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