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What's a SLIC Pin^®? Pin and cotter all in one!

The SLIC Pin (Self-Locking Implanted Cotter Pin) from Pivot Point is a pin and cotter all in one. This one-piece locking clevis pin is cost saving, fast, and secure. It functions as a quick locking pin wherever you need a fast-lock function. It features a spring-loaded plunger that functions as an easy insertion ramp. This revolutionary fastening pin is very popular and used successfully in a wide range of applications.
Learn more.

Engineering challenge: Which 3D-printed parts will fade?

How does prolonged exposure to intense UV light impact 3D-printed plastics? Will they fade? This is what Xometry's Director of Application Engineering, Greg Paulsen, set to find out. In this video, Paulsen performs comprehensive tests on samples manufactured using various additive processes, including FDM, SLS, SLA, PolyJet, DLS, and LSPc, to determine their UV resistance. Very informative. Some results may surprise you.
View the video.

Copper filament for 3D printing

Virtual Foundry, the company that brought us 3D-printable lunar regolith simulant, says its popular Copper Filamet™ (not a typo) is "back in stock and ready for your next project." This material is compatible with any open-architecture FDM/FFF 3D printer. After sintering, final parts are 100% pure copper. Also available as pellets. The company says this is one of the easiest materials to print and sinter. New Porcelain Filamet™ available too.
Learn more and get all the specs.

Copper foam -- so many advantages

Copper foam from Goodfellow combines the outstanding thermal conductivity of copper with the structural benefits of a metal foam. These features are of particular interest to design engineers working in the fields of medical products and devices, defense systems and manned flight, power generation, and the manufacture of semiconductor devices. This product has a true skeletal structure with no voids, inclusions, or entrapments. A perennial favorite of Designfax readers.
Learn more.

Full-color 3D-printing Design Guide from Xometry

With Xometry's PolyJet 3D-printing service, you can order full-color 3D prints easily. Their no-cost design guide will help you learn about different aspects of 3D printing colorful parts, how to create and add color to your models, and best practices to keep in mind when printing in full color. Learn how to take full advantage of the 600,000 unique colors available in this flexible additive process.
Get the Xometry guide.

Tech Tip: How to create high-quality STL files for 3D prints

Have you ever 3D printed a part that had flat spots or faceted surfaces where smooth curves were supposed to be? You are not alone, and it's not your 3D printer's fault. According to Markforged, the culprit is likely a lack of resolution in the STL file used to create the part.
Read this detailed and informative Markforged blog.

Test your knowledge: High-temp adhesives

Put your knowledge to the test by trying to answer these key questions on how to choose the right high-temperature-resistant adhesive. The technical experts from Master Bond cover critical information necessary for the selection process, including questions on glass transition temperature and service temperature range. Some of the answers may surprise even the savviest of engineers.
Take the quiz.

Engineer's Toolbox: How to pin a shaft and hub assembly properly

One of the primary benefits of using a coiled spring pin to affix a hub or gear to a shaft is the coiled pin's ability to prevent hole damage. Another is the coiled pin absorbs wider hole tolerances than any other press-fit pin. This translates to lower total manufacturing costs of the assembly. However, there are a few design guidelines that must be adhered to in order to achieve the maximum strength of the pinned system and prevent damage to the assembly.
Read this very informative SPIROL article.

What's new in Creo Parametric 11.0?

Creo Parametric 11.0 is packed with productivity-enhancing updates, and sometimes the smallest changes make the biggest impact in your daily workflows. Mark Potrzebowski, Technical Training Engineer, Rand 3D, runs through the newest functionality -- from improved surface modeling tools to smarter file management and model tree navigation. Videos provide extra instruction.
Read the full article.

What's so special about wave springs?

Don't settle for ordinary springs. Opt for Rotor Clip wave springs. A wave spring is a type of flat wire compression spring characterized by its unique waveform-like structure. Unlike traditional coil springs, wave springs offer an innovative solution to complex engineering challenges, producing forces from bending, not torsion. Their standout feature lies in their ability to compress and expand efficiently while occupying up to 50% less axial space than traditional compression springs. Experience the difference Rotor Clip wave springs can make in your applications today!
View the video.

New Standard Parts Handbook from JW Winco

JW Winco's printed Standard Parts Handbook is a comprehensive 2,184-page reference that supports designers and engineers with the largest selection of standard parts categorized into three main groups: operating, clamping, and machine parts. More than 75,000 standard parts can be found in this valuable resource, including toggle clamps, shaft collars, concealed multiple-joint hinges, and hygienically designed components.
Get your Standard Parts Handbook today.

Looking to save space in your designs?

Watch Smalley's quick explainer video to see how engineer Frank improved his product designs by switching from traditional coil springs to compact, efficient wave springs. Tasked with making his products smaller while keeping costs down, Frank found wave springs were the perfect solution.
View the video.

Top die casting design tips

You can improve the design and cost of your die cast parts with these top tips from Xometry's Joel Schadegg. Topics include: Fillets and Radii, Wall Thicknesses, Ribs and Metal Savers, Holes and Windows, Parting Lines, and more. Follow these recommendations so you have the highest chance of success with your project.
Read the full Xometry article.

What's the latest from 3D Systems? Innovations for different industries, processes

3D Systems unveiled several new solutions at the RAPID+TCT 2025 show in April designed to change the way industries innovate. From new 3D printers and materials for high-mix, low-volume applications to marked improvements in how investment casting can be done, learn what is the state of the art from the original inventors of 3D printing.
Read the full article.

Clever! Indexing plungers with chamfered pins

JW Winco has developed a new type of indexing plunger -- GN 824 -- that can independently latch into edges and grooves. This is made possible by a chamfered plunger pin. When the chamfered pin encounters a raised latching geometry, it retracts and then springs back out again once it reaches the latching point. This new indexing plunger can be ordered with axial thread for fastening and a black plastic knob for operating the indexing plunger. In a clever design, the plunger pin can be adjusted by 360 degrees to ensure that it encounters the mating surface perpendicularly. This hardware is well suited for transport frames, mechanisms, or covers that need to be locked in place quickly and securely, especially without the need for manual intervention.
Learn more.

Sun-soaking device turns water into superheated steam

The high-temperature steam might be used in remote regions to cook, clean, or sterilize medical equipment.

MIT engineers have built a device that soaks up enough heat from the sun to boil water and produce "superheated" steam hotter than 100 degrees Celsius, without any expensive optics.

On a sunny day, the structure can passively pump out steam hot enough to sterilize medical equipment, as well as to use in cooking and cleaning. The steam may also supply heat to industrial processes, or it could be collected and condensed to produce desalinated, distilled drinking water.

The outdoor experiment on the MIT roof. Steam-generating device is mounted over a basin of water, placed on a small table, and partially surrounded by a simple, transparent solar concentrator. Researchers measured the temperature of the steam produced over the course of the test day, Oct. 21, 2017. [Credit: Courtesy of the researchers, Thomas Cooper et al.]

 

 

 

 

The researchers previously developed a sponge-like structure that floated in a container of water and turned the water it absorbed into steam. But a big concern was that contaminants in the water caused the structure to degrade over time. The new device is designed to be suspended over the water to avoid any possible contamination.

The suspended device is about the size and thickness of a small digital tablet or e-reader, and it is structured like a sandwich: The top layer is made from a material that efficiently absorbs the sun's heat, while the bottom layer efficiently emits that heat to the water below. Once the water reaches the boiling point (100 C), it releases steam that rises back up into the device, where it is funneled through the middle layer -- a foam-like material that further heats the steam above the boiling point, before it's pumped out through a single tube.

"It's a completely passive system -- you just leave it outside to absorb sunlight," says Thomas Cooper, assistant professor of mechanical engineering at York University, who led the work as a postdoc at MIT. "You could scale this up to something that could be used in remote climates to generate enough drinking water for a family, or sterilize equipment for one operating room."

The team's results are detailed in a paper published in Nature Communications. The study includes researchers from the lab of Gang Chen, the Carl Richard Soderberg Professor of Power Engineering at MIT.

A clever combination
In 2014, Chen's group reported the first demonstration of a simple, solar-driven steam generator, in the form of a graphite-covered carbon foam that floats on water. This structure absorbs and localizes the sun's heat to the water's surface (the heat would otherwise penetrate down through the water). Since then, his group and others have looked to improve the efficiency of the design with materials of varying solar-absorbing properties. But almost every device has been designed to float directly on water, and they have all run into the problem of contamination, as their surfaces come into contact with salt and other impurities in water.

The team decided to design a device that instead is suspended above water. The device is structured to absorb short-wavelength solar energy, which in turn heats up the device, causing it to reradiate this heat, in the form of longer-wavelength infrared radiation, to the water below. Interestingly, the researchers note that infrared wavelengths are more readily absorbed by water, versus solar wavelengths, which would simply pass right through.

For the device's top layer, they chose a metal ceramic composite that is a highly efficient solar absorber. They coated the structure's bottom layer with a material that easily and efficiently emits infared heat. Between these two materials, they sandwiched a layer of reticulated carbon foam -- essentially, a sponge-like material studded with winding tunnels and pores, which retains the sun's incoming heat and can further heat up the steam rising back up through the foam. The researchers also attached a small outlet tube to one end of the foam, through which all the steam can exit and be easily collected.

Finally, they placed the device over a basin of water and surrounded the entire setup with a polymer enclosure to prevent heat from escaping.

"It's this clever engineering of different materials and how they're arranged that allows us to achieve reasonably high efficiencies with this noncontact arrangement," Cooper says.

Full steam ahead
The researchers first tested the structure by running experiments in the lab using a solar simulator that mimics the characteristics of natural sunlight at varying, controlled intensities. They found that the structure was able to heat a small basin of water to the boiling point and produce superheated steam, at 122 C, under conditions that simulated the sunlight produced on a clear, sunny day. When the researchers increased this solar intensity by 1.7 times, they found the device produced even hotter steam, at 144 C.

On Oct. 21, 2017, they tested the device on the roof of MIT's Building 1 for the first time, under ambient conditions. The day was clear and bright, and to increase the sun's intensity further, the researchers constructed a simple solar concentrator -- a curved mirror that helps to collect and redirect more sunlight onto the device, thus raising the incoming solar flux, similar to the way a magnifying glass can be used to concentrate a sun's beam to heat up a patch of pavement.

With this added shielding, the structure produced steam in excess of 146 C over the course of 3.5 hours. In subsequent experiments, the team was able to produce steam from sea water, without contaminating the surface of the device with salt crystals. In another set of experiments, they were also able to collect and condense the steam in a flask to produce pure, distilled water.

Chen says that, in addition to overcoming the challenges of contamination, the device's design enables steam to be collected at a single point, in a concentrated stream, whereas previous designs produced a more dilute spray.

"This design really solves the fouling problem and the steam collection problem," Chen says. "Now we're looking to make this more efficient and improve the system. There are different opportunities, and we're looking at what are the best options to pursue."

Source: MIT

Published January 2019

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