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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.

Stretchable, flexible, recyclable: Princeton engineers create fantastic 3D-printed plastic

Alice Fergerson (left), a graduate student, and Emily Davidson (right), an assistant professor of chemical and biological engineering, demonstrate a new, tunable, stretchable material that can be carefully structured for different properties. [Credit: Princeton Engineering]

 

 

 

 

By John Sullivan, Princeton Engineering

Princeton University engineers have developed an easily scalable 3D-printing technique to manufacture soft plastics with programmed stretchiness and flexibility that are also recyclable and inexpensive -- qualities not typically combined in commercially manufactured materials.

In an article in the journal Advanced Functional Materials, a team led by Emily Davidson reported that they used a class of widely available polymers called thermoplastic elastomers to create soft 3D-printed structures with tunable stiffness. Engineers can design the print path used by the 3D printer to program the plastic's physical properties so that a device can stretch and flex repeatedly in one direction while remaining rigid in another. Davidson, an assistant professor of chemical and biological engineering, said this approach to engineering soft architected materials could have many uses, such as soft robots, medical devices and prosthetics, strong lightweight helmets, and custom high-performance shoe soles.

The key to the material's performance is its internal structure at the tiniest level. The research team used a type of block copolymer which forms stiff cylindrical structures that are 5 to 7 nanometers (nm) thick (for comparison, human hair measures about 90,000 nm) inside a stretchy polymer matrix. The researchers used 3D printing to orient these nanoscale cylinders, which leads to a 3D-printed material that is hard in one direction but soft and stretchy in nearly all others. Designers can orient these cylinders in different directions throughout a single object, leading to soft architectures that exhibit stiffness and stretchiness in different regions of an object.

"The elastomer we are using forms nanostructures that we are able to control," Davidson said. This allows designers a great degree of control over finished products. "We can create materials that have tailored properties in different directions."

The first step in developing this process was choosing the right polymer. The researchers chose a thermoplastic elastomer, which is a block copolymer that can be heated and processed as a polymer melt, but which solidifies into an elastic material when it cools. At the molecular level, polymers are long chains of linked molecules. Traditional homopolymers are long chains of one repeating molecule, whereas block copolymers are made of different homopolymers connected to each other. These different regions of a block copolymer chain are like oil and water -- they separate instead of mixing. The researchers used this property to produce material with stiff cylinders within a stretchy matrix.

The researchers used their knowledge of how these block copolymer nanostructures form and how they respond to flow to develop a 3D-printing technique that effectively induces alignment of these stiff nanostructures. The researchers analyzed the way that printing rate and controlled under-extrusion could be used to control the physical properties of the printed material.

Alice Fergerson, a graduate student at Princeton and the article's lead author, spoke about the technique and the key role played by thermal annealing -- the controlled heating and cooling of a material.

"I think one of the coolest parts of this technique is the many roles that thermal annealing plays -- it both drastically improves the properties after printing, and it allows the things we print to be reusable many times and even self-heal if the item gets damaged or broken."

This tiny vase is rigid in one direction and flexes in others. [Credit: Princeton Engineering]

 

 

Davidson said that one of the goals of the project was to create soft materials with locally tunable mechanical properties in a way that is both affordable and scalable for industry. It is possible to create similar structures with locally controlled properties using materials such as liquid crystal elastomers. However, Davidson said those materials are both expensive (upwards of $2.50 per gram) and require multi-stage processing involving carefully controlled extrusion followed by exposure to ultraviolet light. The thermoplastic elastomers used in Davidson's lab cost about a cent per gram and can be printed with a commercial 3D printer.

The researchers have shown their technique's ability to incorporate functional additives into the thermoplastic elastomer without reducing the ability to control material properties. In one example, they added an organic molecule developed by Professor Lynn Loo's group that makes the plastic glow red after exposure to ultraviolet light. They also demonstrated the printer's ability to produce complex and multi-layered structures including a tiny plastic vase and printed text that used sharp turns to spell out PRINCETON.

Annealing plays a key role in their process by increasing the perfection of the order of internal nanostructures. Davidson said annealing also enables self-healing properties of the material. As part of the work, the researchers cut a flexible sample of the printed plastic and reattached it by annealing the material. The repaired material demonstrated the same characteristics as the original sample. The researchers said they observed "no significant differences" between the original and the repaired material.

As a next step, the research team expects to begin exploring new 3D-printable architectures that will be compatible with applications such as wearable electronics and biomedical devices.

Published December 2024

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