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Drain Your Silverware With an Elephant! 3D Printing a 3DGuyDubai Model!

Binary Watch #WearableWednesday

From Sverd Industries on Hackster.io:

I’ve always been fascinated by both interesting ways of telling the time and binary code. It’s amazing the amount of information can be stored in simple ON/OFF signals. I knew I wanted a new wrist watch so why not combine binary code with a wrist watch, and do it as an awesome DIY project?

This is the kind of idea that lodged itself in the back of my mind. Always present and constantly evolving until it reached a saturation point where the project had to be done!

There were several challenged that had to solved to make it the watch of my dreams. Most of these challenges can be traced back to the small area of a wrist watch. It would have been easy to make a big or ugly watch, but that’s simply not what I wanted from this project.

I will take you through the process from idea to making your own binary wrist watch you can wear with pride.

Let’s get started!

Read more and see more on YouTube and Thingiverse

Every Wednesday is Wearable Wednesday here at Adafruit! We’re bringing you the blinkiest, most fashionable, innovative, and useful wearables from around the web and in our own original projects featuring our wearable Arduino-compatible platform, FLORA. Be sure to post up your wearables projects in the forums or send us a link and you might be featured here on Wearable Wednesday!

CT Scanning Proves to be an Effective Method for Qualifying 3D Printed Parts

Many things can go wrong with an additively manufactured part, and those things are not always visible. Particularly in powder-based 3D printing, there are several things that can happen during the print that cause issues such as cracking and voids, which may be inside the part and invisible to the eye. There are ways, however, of discovering these defects without having to break apart the part and look inside. In a new paper entitled “The Role of Computed Tomography in Additive Manufacturing,” which you can access here, a group of researchers argue that computed tomography, or CT scanning, is the most effective way of performing quality checks on 3D printed parts.

Complex parts are especially challenging to inspect for quality purposes, as they can contain internal channels or structures that are prone to voids or inclusions, which are unmelted particles or powder residues. These flaws are difficult for traditional non-destructive testing, or NDT, techniques to fully assess. These techniques include ultrasonic, infrared, eddy current, radiographic inspection, and light-based technologies. Optical methods of defect detection can only detect flaws at the surface or through a surface opening.

“Eddy-current testing and ultrasonic techniques can detect defects within the volume if they are not located very deep inside the testing sample, but the one drawback is the limited spatial resolution of detection, which is in the millimeter range or some fraction of millimeters in the most optimal situations and for even more limited depths into the surface,” the researchers explain.

The best method for nondestructive inspection of complex geometries inside a part, they argue, is X-ray CT, which has a resolution from millimeter to micrometer ranges, and even sub-micron levels in some cases. In fact, they continue, in many cases it is the only viable option. It can detect cracks, porosity, dimensional deviations from CAD models, and powder residues or inclusions.

“In general, tactile CMMs (coordinate measuring machines) or optical measuring instruments like laser scanners are limited to the measurement of the external surface of an AM part and can provide additional measurements for partial qualification of CT measurements,” the researchers add. “In addition, tactile CMMs can produce compressive stresses and friction during sliding that could produce wear at the surface. In contrast, X-ray CT eliminates the above difficulties because it is a non-contact technique that can access internal features.”

X-ray CT analysis of a 3D printed turbine blade

The importance of qualification for additively manufactured parts cannot be overstated. If a part is being used for an aerospace application, for example, it’s absolutely critical that that part is perfect, with no hidden flaws. There are many methods for checking the quality of parts, but most of them come up short in terms of detecting flaws that are hidden deep inside a part. The paper goes on to highlight a case study in which X-ray CT was able to detect minute deviations in dimension from the CAD model to the final part, as well as material inclusions in the internal cavities.

It can be challenging to use CT technology with metal parts, as metal parts can scatter X-rays, disrupting CT reconstructions and producing unwanted artifacts in the data. The solution, the researchers say, is to use a 2D fan beam of X-rays and a linear detector, which can reduce the scattering. Overall, they conclude, CT technology is an effective method of non-destructive testing.

Authors of the paper include Herminso Villaraga-Gómez, Christopher M. Peitsch, Andrew Ramsey and Stuart T. Smith.

Discuss this and other 3D printing topics at 3DPrintBoard.com or share your thoughts below.

Russia: Researchers Examine Porosity Issue in 3D Printing

3D printing opens up infinite new realms of creativity to innovators around the world, whether they are bioprinting or making surgical implants, cars, rocket engine components, or running shoes. Along with all that wonderful opportunity for invention, however, comes pressure. While it is understandable that some objects are still works in progress, most of us want the end product to be as perfect as possible—not only out of self-respect, but also out of respect for a technology just coming into its own in the mainstream, and a need for proper aesthetics, functionality, and productivity.

Now, researchers from the Russian Academy of Sciences have found ways to improve upon 3D printing, outlined in ‘Improvement of quality of 3D printed objects by elimination of microscopic structural defects in fused deposition modeling,’ by Evgeniy G. Gordeev, Alexey S. Galushk, and Valentine P. Ananikov. Porosity issues are a reason for many failures in FDM 3D printing, despite its usefulness in so many different applications, to include medicine, biochemistry, engineering, chemical sciences, and more. Issues with structural weakness and porosity often make the use of FDM 3D printing challenging though, whether just in prototyping or other manufacturing processes.

In assessing FDM 3D printing, the research team used materials such as PLA, ABS, PETG, PP, Nylon (polyamide), and carbon-filled Nylon while they examined the following:

Filament feed rate
Wall geometry
G-code defined wall structure

(A) cylindrical test tube, (B) hollow entity of cubical shape, (C) spherical flask. In the top view, arrows indicate outgassing.

As they optimized feed rate and structure, the researchers were able to significantly improve 3D printing quality—even with more basic hardware and materials. In evaluating, they printed with a Picaso 250 Designer Pro (PICASO 3D) with a 0.3 mm diameter nozzle, creating objects like cylinders, cones, spheres, pyramids, and cubes—all of which they performed numerous experiments on.

“It turned out that under standard conditions cylindrical objects had the minimum number of pores and the best quality of 3D printing,” stated the researchers. “Conical objects had larger pores uniformly distributed over the surface. For a spherical shape, the largest number of pores was observed in the region of poles lying on the axis perpendicular to the planes of the layers, while the equatorial region retained impermeability.”

“A combination of cylindrical and conical shapes in one object resulted in a uniform distribution of a small number of pores in the wall of the cylindrical portion, and a much larger number of pores in the conical portion. In plane-faced products (e.g. hexagonal pyramid and cube), the most porous areas were found at the edges, that was, in the neighborhood of the joints between the faces. The observed dependence of porosity on the geometric shape or its specific area is explained by the corresponding differences in the mode of layer positioning: in cubical and cylindrical products, the layers are arranged exactly one above the other, so the interlayer contact is most effective. In conical products, the layers are arranged with a certain offset, that is, stepwise, which makes the interlayer contact less effective.”

Functional assessment of 3D printing quality for objects of different shapes.
All objects are printed with identical parameters at k = 0.9 from PLA: (A) cylinder, (B) cone, (C) sphere, (D) compound shape, (E) pyramid, (F) cube. The diagrams below show the distribution/densities of the pores. Red areas have maximal porosity/permeability; green areas are relatively impermeable; blue color designates junctions with the air compressor.

The team states that they found ‘edges and vertices’ to have more defects than other shapes in the experiments.

“Among the shapes with smooth outlines, conical and spherical elements of irregular curvature are most vulnerable, whereas flat and cylindrical surface areas are most resistant to the pore formation,” stated the researchers.

The researchers also discovered that thin-walled objects became ‘untenable’ in terms of sealant. Reversing this with thicker walls allowed for less pores and better success in 3D printing:

“Thus, to minimize the porosity, the proper filling of the inner space should be additionally controlled by verification of the G-code suggested by the slicer software. The more homogeneous the intermediate layer of the wall is, the more impermeable the wall of the product will be, since all the seams will be securely insulated from each other.”

Permeability was shown to be greatly affected by the following conditions:

Extrusion multiplier
Wall thickness
Internal filling
Temperature
Materials
Shape

“The product properties can be affected by the feeder construction, presence/absence of a closed case, heating mode of the working platform, extruder cooling system, etc.,” concluded the researchers. “Despite that, with proper optimization of printing conditions, commercial desktop 3D printers can be suitable for the production of sealed containers for various applications. The proposed quality assessment procedure allows the gradual improvement of the quality of 3D printed objects by elimination of structural defects.”

Find out more about the research conducted at the Russian Academy of Sciences here.

PP tubes as chemical reaction vessels in comparison with conventional glass test tubes. Values of k are given below for each 3D-printed tube. Performance in the studied chemical transformation is illustrated by product yield (in %) in each studied case, where ≥ 90% efficiency corresponds to excellent performance.

What do you think of this news? Let us know your thoughts! Join the discussion of this and other 3D printing topics at 3DPrintBoard.com.

Maryland Researchers 3D Print Middle Ear Prostheses

While printing finds itself in wide use among the medical prosthesis community, there are certain organs that are fairly elusive. Although 3D printing offers precise control over minute details, there are always worries about part quality and precision. Parts like the ear, particularly for sufferers of hearing loss, can be intricate pieces to produce as […]

The post Maryland Researchers 3D Print Middle Ear Prostheses appeared first on 3D Printing.

Unpacking America’s downloadable 3D printed guns

Today is the day that Defense Distributed’s 3D printable gun models were due to go online. In case you missed it, on 10 July 2018, the U.S. Department of Justice decided to overturn a ban on the digital distribution of files that can be downloaded and used to make 3D printed guns. The debate, and […]

REVIEW: The 3DGence INDUSTRY F340, a powerful PEEK 3D printing workhorse

The 3DGence INDUSTRY F340 is a dual nozzle industrial 3D printer suitable for working with a range of functional materials including the high grade thermoplastic PEEK. 3D Printing Industry recently visited Poland to test the 3DGence F340 and find out if this industrial additive manufacturing system lives to the manufacturer’s claims. As an FFF/FDM 3D […]

3DPrint.com Interviews Cole Brubaker of Halmos Technologies for nanofunctionalized materials for 3D printing

A few weeks ago we read about Cole Brubaker’s fascinating research at Vanderbilt University on nanofunctionalized materials for 3D printing. Together with a team, he had looked into gold nanoparticles and how these could be used to spot defects in 3D prints. The idea to use nanoparticles for quality control in 3D printing was novel and could have very wide-reaching applications in 3D printing. We as an industry are using many different settings and machines to make unique parts and seeing if these parts have been built properly is specifically problematic for 3D printing. Using nanoparticles fo QA and also maybe QI excited us. Furthermore, post 3D printing these parts are tossed into the world, and then what? When do we know when a part has outlived its usefulness and is due to be replaced? Construction and manufacturing could be much safer if we had intelligent materials which told us when they needed to be serviced. Nanotechnology was also a very interesting area for us especially since we believe strongly in nanoprinting and the value-add that this will create for a more optimized world. Another hype area is IoT which wishes to make the whole world smart by adding sensors to everything. What if there was a cheaper way? What if you could harness 3D printing and nanotech to have the part be your sensor and your display? What is nanotech and 3D printing could make simple cost-effective parts that would function in the real world while keeping us updated as to their usefulness? We decided to interview Cole Brubaker and were excited to discover that he is now working on a startup Halmos Technologies to commercialize what he discovered at Vanderbilt.

On the left researcher Cole Brubaker stands next to his Phd advisor Kane Jennins.

Cole Brubaker and his Phd advisor at Vanderbilt Kane Jennings.

You’ve completed your PhD and are now working in a business. Are you commercializing one of your inventions? Why this one?

“I will be finishing up my PhD in the next few months, and am excited to continue working on the commercialization of new, functional materials for additive manufacturing with my company Halmos Technologies. One of the largest hurdles facing additive manufacturing and its widespread adoption right now is that of quality control. How can we ensure that a part was printed exactly as it was designed? With the nanofunctionalized materials I have developed during my time at Vanderbilt University, I believe that the ability to quickly and nondestructively inspect parts and materials for defects and missing print layers will be a paradigm in the world of 3D printing. Ensuring quality control will help provide a sense of safety and security in 3D printed parts in its continued adoption across a number of fields and uses.”

What kind of business is it?

“The business will be focused around the production of functional materials for 3D printing and additive manufacturing applications. By focusing on material design, new materials with enhanced material behaviors compared to the traditional PLA and ABS plastics can be developed. This will open the door for a number of new and exciting products and devices that can be constructed with 3D printing.”

We found your research really interesting, the idea to add nanoparticles to a part in order to enable a visual identification of manufacturing defects. Could an approach like that be able to also indicate when a part is end of life?

“Looking forward, the ultimate goal of this technology is to develop novel ‘smart’ materials and parts that are capable of self reporting damage and wear. This would include providing an indication of when a part or structure Is nearing the end of its useable life, or is in need of repair. Ideally we will be able to design materials to provide in situ material state awareness throughout its useable lifespan.”

Could it indicate when an aerospace part has had too much strain or UV?

“Stress and strain monitoring is one application that I am very interested in exploring. By extending the ideas and concepts I have developed with our previous work, the ability to nondestructively, and visually, inspect structures for strain, or other mechanical insults, arising during normal operating procedures and use is a main focus of this technology going forward.”

It is easy to see that this has applications in monitoring bridges or craft. What are other applications possible?

“There are a number of relevant applications this technology could be used for, beyond just civil infrastructure and aerospace components: biomedical implants, tools and molds, prototypes, energy, etc. Nanomaterials have the potential to positively impact a wide range of fields and uses, by enabling 3D printed parts with new material behaviors and responses.”

The UV-Vis spectrophotometer meant to detect the flaws and “read the parts” seems expensive, however. Would other scanning technologies let us have different results with the same approach?

“Right now, this technology is still at a laboratory scale demonstration, which Is why we are using the UV-Vis spectrophotometer to inspect the as-printed parts for detects and flaws that occurred in the manufacturing process. There are a number alternative, handheld optical inspection devices that can be used to monitor and inspect for defects and damage in the field. Ideally, a system which could be inspected and qualified using nothing more than the standard smartphone camera would be the ultimate goal for the technology; enabling rapid inspection at any given moment in the palm of your hands.”

3D printed parts with embedded nanoparticles.

Could you do the same with magnetic particles for example and get much cheaper to scan part?

“Gold nanoparticles are just one example of the types of additive that we can use with 3D printing and additive manufacturing applications. We selected gold nanoparticles due to their flexibility in synthesis, design procedures, as well as the ability to functionalize the surface of the gold nanoparticles to enable additional sensing and inspection capabilities. The same approach could be extended to a wide variety of nanomaterial systems, such as magnetic particles, based on the desired use of the material. We have also demonstrated the ability to incorporate quantum dots within the 3D printing process to fabricate fluorescent materials and displays, where the same approaches can be extended to a variety of material systems.”

There is a lot of hype around nano. Do you really feel it will change a lot?

“Nanotechnology is booming. The number of relevant applications and uses of nanotech seems to be growing daily, and I don’t see it slowing down anytime soon. Nanotechnology is so appealing because of the unique material properties that are enabled at these reduced length scales. By changing the relative size and material composition, nanotech with enhanced mechanical, thermal, optical and electrical properties can be developed. And using the approach we have developed, our goal is to bridge the gap between the nano and bulk scale, by enabling larger scale 3D printed parts and structures with the enhanced material behaviors enabled by nanotechnology. This would be a true paradigm shift in the world of additive manufacturing.”

Are there dangers as well?

“One thing that is important to consider is the impact that functionalization has on the overall material properties, and understanding how the material behaves following the inclusion of nanomaterials, or any other additives, to the host polymer.”

Your research really required an interdisciplinary team of chemists, engineers, civil engineers, biomedical engineers and more. At science’s boundary is this kind of collaborative work between fields more a requirement nowadays?

“I definitely see science moving more towards an interdisciplinary approach, not only in academia but also in industry. When you bring together a group of people each with different backgrounds, experience, training and knowledge, there is really no limit to the things that can be accomplished. It gives everyone a fresh perspective and new ways of thinking about problems and questions that you may have not otherwise considered. Working across academic boundaries and bringing together these groups on interdisciplinary researchers and thinkers will continue to help open doors, and help push forward additive manufacturing and 3D printing.”

Has scientific research gone from an individual affair to more of a team sport?

“Research has definitely become a team sport. Even in additive manufacturing, the field as a whole is a perfect example of that transition. Mechanical and electrical engineers are constantly interfacing with chemists and material scientists to design and optimize systems and materials to arrive at a common end goal: the ability to rapidly manufacture functional parts and structures.”

3D printing functional nanoparticle embedded materials for quality assurance and quality inspection on an Ultimaker 3

You also work on quantum dots. I know we’re going to be hearing much more about them. What do I need to know about quantum dots?

“Quantum dots are semi-conducting nanoparticles that have unique optical and emissive characteristics that can be tuned according to their size and material composition. It is this emissive characteristic of quantum dots that most people are excited about. They have been used for everything ranging from solar cells, displays, biological tracking and most recently in TVs that you can buy at your local electronics store. With the development of large-scale production facilities, I think the use of quantum dots are going to become more common in every day applications and uses. Our work with quantum dots in 3D printing is an exciting representation of how we can begin to manufacture and print large scale structures with these tunable optical characteristics enabled through nanotechnology and quantum dots in particular.”

I wouldn’t immediately think of Nashville Tennessee as the place to found a technology startup?

“Tennessee is quickly becoming a hot spot for new startups and tech companies. There are a number of local and state-sponsored programs geared towards helping small businesses succeed here in Tennessee. And even more, just about 3 hours away from Nashville, at Oak Ridge National Laboratory, the Manufacturing Demonstration Facility is one of the largest additive manufacturing and 3D printing research and development centers in the country. Having access to experts in the field within just a few hours drive is an unbeatable benefit to continuing to work with 3D printing in Nashville.”

Mathematics Jewelry Uses and Patents I-Beam based Jewels

New York based couple structural engineer Beth Macri and software engineer Jason Macri have started a jewlery business together. The tech duo was inspired through trying to use 3D printing to create unique jewlery for a friend. An I-Beam served as the inspiration for an architectural piece of jewlery that shows you the name of the wearer from another angle. The I-Beam jewlery is actually extruded letters and one can choose one to match your jewel. Their jewlery brand is called Mathematics and it is made through 3D Printing and lost wax casting. 3DPrint.com interviewed Beth to see how her jewlery brand came about.

Why did you start this business?

I went back to school for parametric arch and fell in love with 3D printing technology. I wanted to use this technology on a smaller scale and started to think of jewelry concepts that couldn’t be achieved without the 3D printing technology. Initially I was working on generative algorithm jewelry, however a friend of mine was having a baby and I wanted to make a unique letter necklace to commemorate the occasion.

Why an I-Beam?

The I-Beam was a part of my subconscious after my years of working as a structural engineer doing high end architecture.

Who is your target audience?

There really isn’t a target audience as we have customers ranging from college students to Fortune 500 CEO’s. Each necklace has a different style and a different meaning so it can tell the story for just about anymore.

What is your goal for this business?

The name was recently changed from Beth Macri to Mathematics, as Mathematics is a ubiquitous word and we want our jewelry to be ubiquitous.

How does the jewlery get made?

I didn’t develop the software, for my product I use basic Rhino modeling techniques and work alongside our local casting house that is using the latest in 3D printing technologies in jewelry.

Are you as a designer worried about how many other upcoming jewelry brands there are?

I am not worried about up and coming jewelry designers for two reasons. We have a patented product, so we are the only ones who can create these necklace. But we are also friends with many designers from our industry, and welcome more to our world; it’s empowering and fulfilling to work alongside so many other unique and wonderful designers.

The Mathematics Founders Beth and Jason Macri

What is it like working with 3D printing?

It’s been a game changer. I wouldn’t be in business if it wasn’t for this technology. This technology pushes the boundary of what can be done in the jewelry industry.

I’ve noticed that with the demise of Facebook there is no way to indicate to the world that you are in a relationship. Perhaps this can be the way?

Our jewelry is the antithesis of sharing yourself with the rest of the world; it’s whatever you want it to be but it’s also private and personal to the wearer. We think this is a nice reprieve from oversharing with the rest society.

The most interesting thing about Mathematics jewelry was that the couple state that they patented the jewels. This is quite remarkable considering how much prior art there is in using extruded letters. A design grant was given to Beth Macri in 2015 for extruded letters that are in the form of a beam. One part of me is simply flabbergasted that as late as a few years ago someone had not registered this. Another part of me doesn’t like being restricted in the form that I can create. What do you think?

3D Printed Guns: Bad People can go on Instagram and get an Instagun

Lawmakers speak out against 3D printed guns with Senator Richard Blumenthal saying that “these ghost guns are the new wave of American gun violence.” Senator Edward Markey says that “Donald Trump would be responsible for every 3D Printed AR 15 roaming the streets of our country.” Also, he stated, “Beginning tonight at 12:01 AM, bad people can go on Instagram and get an Instagun.” ChuckSchumerr also says that the administration is “enslaved by the NRA.” One gets the impression that these guys are worried about “The Purge.”

We’ve gone from being a $12 billion High tech industry growing at a 30% clip, saving children, repairing pets, providing jobs and being the future of all the things to now being a political football. I’ve worried about this before but this 3D printed gun backlash is actually happening. Lets recap for a moment. We’ve spoken about this topic before and are caught between bringing realism to 3D printed guns and popularizing this even more.

It has always been legal in the United States to make your own homebrew guns 3D printed, or made with whatever the technology. Ghost guns could always be made and 3D printed ghost guns could have been made for 30 years now. What so far over the past 30 years have been the cases when 3D printed ghost guns have been used for crime? What percentage of gun crimes is committed by homemade ghost guns?

Making DIY guns at home has been legal for decades. If you want to sell your gun, then you have to apply to become a gun manufacturer or distributor and your gun has to have a serial number. A group of people looking for controversy did not do this. They were invited on all the talk shows and got more money to 3D print their guns. The 3D printed gun was one guy’s idea but the media attention made it a reality. It is therefore their fault once someone gets killed. By making this a self-fulfilling prophecy and popularizing it they are making it a reality. Meanwhile, the group that first 3D printed guns is using CNC machines to make guns.

Instagun t-Shirt.

A lawsuit gets settled and immediately lawmakers spring into action to defend us from 3D printed guns. The entire media sees this as a new threat. Do none of them realise that ghost guns or 3D printed guns could have been possible for decades?

Meanwhile in these decades have crimes been committed with them? Nope. Criminals have enough guns already and can get them via traditional means. Also, other methods of manufacturing are better than 3D printing for this application.

So now lawmakers are going to spring into action to? Let me guess: implement DRM for 3D Printing as a solution. The result is that we will get separate more restrictive laws for 3D printing in the United States than for other manufacturing technologies. This can only hamper and restrict 3D printing in the United States. By demonizing 3D printing US politicians have undergone a collective failure to think things through today. We had similar freakouts in Australia and other countries before leading to bans of 3D guns but this one may have consequences unlike other things with ghost guns that just blew over.

The US is one of the leading countries in 3D printing and stands to benefit significantly from it. The US government has spent many millions over the years commercializing several 3D printing technologies that are being used for satellites, aircraft, automobiles, medical applications and in industry. With more legislation aimed just at curtailing 3D printing the US risks undoing its earlier efforts. 3D Printing is being put at a disadvantage when compared to other technologies. The US may through this hoopla harm and even retard its growth in 3D printing. US technological leadership will crumble if the US 3D printing industry is hindered uniquely.

By popularizing this issue 3D printing is coming in a negative light. Rather than putting 3D Printers in classrooms, questions will be asked and kids will get less access to 3D printers. US printers will be more expensive and less capable than others because they will need to have DRM. What’s more DRM will not be a workable solution for companies making secret things and new inventions. These companies, therefore, will no longer buy US 3D printers. Any move towards DRM for 3D printing will do irreparable harm to the US portion of the 3D printing industry while other countries will use this to their advantage.

FDM, SLA, Powder bed fusion and BinderJet are US inventions. The US has done a lot of the heavy lifting to commercialize 3D printing and relies on it for next-generation aircraft and other technologies. Now through one week of media fear mongering the US could put itself out of the 3D printing race. Short-term political goals are being placed ahead of the long-term strategic goals of the country.

Could people use the internet to exchange gun plans? Could people use the internet to plot crime? Of course, they could. But, in retrospect, the fear could be real but I think on the whole its been good for the US to have lead the way in building and rolling out the internet globally. Many billions of good.

Now an impactful technology is being smothered and restricted, in the US alone because of lobbyists and collusion. Some big content company wants DRM to restrict 3D printing. Why because we’ll print out their little puppets? Nope, because they’re afraid we’ll print out our own creations. Other politicians want to fan the flames of a problem that they will then “solve.” No one solves anything but oh it is a beautiful democracy theater for us to watch. Being so close to this thing, caring and knowing how it really works makes me worry about how they decide all the other things that I don’t know about.