While it may sound great to sit around and eat cookies all day, the fact is that cookies aren’t particularly healthy because they’re chock full of sugar. But, partially because obesity rates have been increasing over the last few decades, people have been more focused on reducing sugar in tasty foods like cookies, or replacing it with something else altogether, like artificial sweeteners such as sucrose. But another trend has also emerged: that of ‘clean label products’ with few or no additives. Desserts could appeal to both trends if a product’s sweetness is increased in a different way, while its overall sucrose is reduced.

Types of 3D food printing: A) Selective laser sintering, B) Inkjet printing, C) Binder jetting, D) Extrusion-based printing

A fairly new way to prepare sweet treats like cookies is 3D printing. The technology makes it possible to create complex, reproducible 3D structures impossible to make by hand alone, and can also help with more customized nutritional requirements.

Tim Meuleman, a student at Wageningen University & Research in the Netherlands, recently wrote a thesis paper, titled “Sugar reduction in cookies by using 3D food printing,” on using 3D printing to achieve sugar reduction in cookies.

The abstract reads, “3D food printing was used to prepare cookies containing different sugar replacers, and cookies containing different doughs which were layered. The effect of these preparation methods on cookie quality properties was investigated. By doing this it could be observed if 3D food printing could be used for achieving sugar reduction in cookies. The cookies were prepared by 3D food printing a dough, which contained sucrose or a sugar replacer. Correlations between the molecular weight of the sugar replacer used and physicochemical properties like texture, water activity, dry matter content, shape stability and bake stability were investigated. Furthermore, the influence of 3D printing on these properties, and the influence of layering different doughs on these properties was investigated. Also, a sensory analysis was performed, to determine the influence of the layering of doughs on perceived sweetness. The effect of molecular weight was tested for homogeneous cookies containing one of the following sugar (replacers); sucrose, xylitol, maltitol, oligofructose and polydextrose. The conclusion was that the inhomogeneous distribution of sucrose in a sugar reduced cookie by layering with a 3D printer does increase the perceived sweetness in comparison to a sugar reduces cookie where the sucrose is homogeneously distributed. The sugar replacement as well as the printing did have influence on the measured physicochemical properties, however these were only small differences. The layering does have influences on the bake stability and fracture stress, however also only small differences were observed.”

The goal of Meuleman’s thesis was to investigate the effect of different sugar replacements in cookie dough, along with the structuring of the cookies based on properties such as shape stability, taste, and texture.

Texture analysis setup

“3D printing was first used to print doughs containing sugar a single sugar replacer to evaluate the impact of the sugar replacement on 3D printing, on physicochemical attributes like final cookie texture, water activity, dry matter content and shape stability. Different doughs were prepared to find the right recipe suitable for 3D printing,” Meuleman wrote. “Next, it was investigated if printing of different layered structures with alternatively the sucrose containing dough and the dough with a sugar replacer improves the texture and/or taste of the cookies in comparison to cookies with homogeneously distributed sucrose and sugar replacers. The influence of the layering and composition of the layered structure on the final cookie properties were especially examined. Furthermore the effect of printing on the cookies was examined by comparing printed cookies to cookies where the dough was cut to shape in the same dimensions as the printed cookies.”

Meuleman used an adapted version of a recipe for a 3D printable dough that he wrote had been “found by unpublished internal experiments at TNO (The Hague, the Netherlands), acquired via Stefano Renzetti,” and chose the various sugar replacers because of the variations between their molecular weight; this allowed him to observe how cookie properties, like dry matter content and texture, were influenced.

Once cookie dough was prepared with a variety of sugar replacers, Meuleman created a design for 3D printing a rectangular cookie in OpenSCAD, which was then loaded into Slic3r before being fabricated on a byFlow 3D food printer.

Vertical and horizontal design for one cookie layer in Slic3r.

After the cookies were baked, they were packaged in aluminum foil to sit for a day, so the water could redistribute inside before the dry matter content and water activity were measured and the texture analysis was performed.

“The texture of the cookie was determined by a three-point bending test to investigate the influence of the recipe and the structure design on texture. The printability was assessed visually, by determining if the printed structure has the same dimensions, if it resembled the created design and if the dough caused any errors during printing. The stability was assessed by making measurements of the dimensions of the cookie before and after baking. Finally, the taste was evaluated by sensory test,” Meuleman wrote.

He concluded that 3D printing was a good way to lower the sugar content in cookies, because it does not negatively influence the texture and also increases the perceived sweetness without having to add any artificial sweeteners.

Future research could focus on developing dough that is easier to 3D print.

“Other interesting effects that could be investigated are: researching other influences from changing the sugar replacer than the changing the molecular weight of the sugar or sugar replacers, like water binding capacity,” Meuleman concluded. “These influences could also be applied to the data collected in this thesis.”

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A team of researchers led by Jan Schroers, Professor of Mechanical Engineering and Materials Science at Yale, has developed a way to 3D print objects from metallic glass. The material is stronger than metal yet has the pliability of plastic, which makes it extremely valuable. The research is published in a paper entitled “3D printing metals like thermoplastics: Fused filament fabrication of metallic glasses.“

Extrusion-based 3D printing of metals is still a challenge, but bulk metallic glasses, or BMGs, can undergo continuous softening upon heating, like thermoplastics can. The research team, which also included researchers from Desktop Metal as well as MIT, demonstrated that BMGs can be used to create solid, strong metal components under ambient conditions similar to those in thermoplastic 3D printing.

“It was even surprising to us how practical this process is once we had the processing conditions figured out,” Schroers said.

Metal 3D printing, while gradually becoming more accessible and affordable, is still quite costly, and powder-based 3D printing is prone to flaws and imperfections, which make it even more expensive. The BMG research could save a lot of money and resources for manufacturers, and also eliminate the need to choose between the benefits of thermoplastics and metals.

The researchers worked with a well-characterized and readily available BMG material made from zirconium, titanium, copper, nickel and beryllium. They used amorphous rods one millimeter in diameter and 700 millimeters in length. They used an extrusion temperature of 460°C and an extrusion force of 10 to 1000 Newtons to force the softened fibers through a 0.5 diameter nozzle. A surprise came when they characterized the 3D printed parts.

“We expected high strength in the parallel-to-the-printing orientation, but were very surprised by the strength in the perpendicular orientation,” said Jittisa Ketkaew, a co-author and graduate student in the Schroers lab.

In theory, a wider range of BMGs can also be 3D printed using the researchers’ method.

“We have shown theoretically in this work that we can use a range of other bulk metallic glasses and are working on making the process more practical and commercially usable to make 3D printing of metals as easy and practical as the 3D printing of thermoplastics,” said Schroers.

There is potential for this method to be used in numerous applications, said Punnathat Bordeenithikasem, a co-author and recent Yale graduate who is currently working as a postdoctoral fellow at the NASA Jet Propulsion Laboratory, California Institute of Technology.

“Beyond prototyping, the achievable properties of the printed parts accompanied by the versatility in part design makes this 3D printing technology suitable for fabricating high-performance components for medical, aerospace, and spacecraft applications,” said Bordeenithikasem.

Authors of the paper include Michael A. Gibson, Nicholas M. Mykulowycz, Joseph Shim, Richard Fontana, Peter Schmitt, Andrew Roberts, Jittisa Ketkaew, Ling Shao, Wen Chen, Punnathat Bordeenithikasem, Jonah S. Myerberg, Ric Fulop, Matthew D. Verminksi, Emanuel M. Sachs, Yet-Ming Chiang, Christopher A. Schuh, A. John Hart, and Jan Schroers.

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Imagine not only holding a tiny ecosystem in your hand, but then eating it, in just a bite or two. That’s the concept behind Edible Growth, a 3D printed “mini vegetable garden” created by Eindhoven-based designer Chloé Rutzerveld. Rutzerveld designed the idea back in 2014, and since then, Edible Growth has grown in popularity, having been displayed in North America, Asia and Europe. Currently, the design is being showcased in Brazil’s Museum of Tomorrow, and is also featured in Rutzerveld’s new book, which was published last week.

Chloé Rutzerveld [Image: Paul Bellaart]

Edible Growth consists of a spherical 3D printed crust with several holes in it. Inside is “edible soil” filled with yeast, seeds and spores that, within days, grow into plants and mushrooms that poke through the holes in the crust, becoming a bite-sized garden that is both adorable and nutritious.

One issue with 3D printing things like fruit and vegetables is that processing them into printable paste causes a significant loss of nutrients. By growing plants inside a 3D printed case, Rutzerveld allows them to keep their original form and all of their nutritional value, while employing 3D printing to create something new and exciting. Four years after introducing the concept for the first time, Rutzerveld reflected upon the fame of Edible Growth.

“Edible Growth was my graduation project at the TU/e  in 2014,” she told the Dutch Institute of Food and Design. “It is a critical project about the use of additive manufacturing techniques which proposes to use the technology as a means to enhance natural growth instead of using the printer merely as a form-machine to create crazy shapes of chocolate, sugar and pasta. I think it went viral because it was the right time to show a skeptical and different view on 3D food printing. Also the picture of my roommate eating the prototype and a very realistic stop motion of how it grows, made people think that Edible Growth was not a prototype / future food concept but that we could already print edible ecosystems.

“Now, 4 years after the launch of the project the TEDx presentation (Calgary 2015) has over 52.000 views and at least once every two weeks I get an email concerning a question, invitation or proposal related to Edible Growth. Crazy! When I just started my studio in 2014 I didn’t want to be known as the 3D food printing girl – I thought it was very limiting but it also created a lot of pressure to come up with something new, which was as good or even better. But after a while I embraced it, because who cares how people find you. It matters that they find me somehow and are interested in the way of thinking to start something new, together.”

Edible Growth shows not only how food can be creatively 3D printed, but how it can be eaten while still growing, and how food can be grown inside the home to lessen the demand for huge agricultural tracts of land.

Rutzerveld’s other works include a plant-based stroopwafel and an experimental meat cookbook. She may not have wanted to be known as the “3D food printing girl,” but Edible Growth has opened up plenty of doors for her to explore the way food is prepared, eaten, and considered. Her book, Food Futures, will be available worldwide beginning in early 2019.

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Some accessories prepared by ultraviolet-assisted 3D printing.

There are many advantages to ultraviolet (UV)-curable systems, like energy saving, rapid curing, environmentally friendly, and high cost performance. These systems are used often with UV-assisted 3D printing, which deposits layers of photocurable liquid polymer crosslinked by an external UV light source to make an object. Silicone materials are promising for 3D printing use due to their unique properties, like thermal resistance, good transparency, and UV resistance.

A team of researchers from Hangzhou, China recently published a paper, titled “Preparation and performance of ultraviolet curable silicone resins used for ultraviolet cured coating and ultraviolet-assisted 3D printing materials,” that detailed how they synthesized a type of UV-curable silicone resin “by an easy controlled method of sol-gel with 3-methacryloxypropyltrimethoxysilane, methyltrimethoxysilane and dimethyldiethoxylsilane.”

The abstract reads, “Types of curable methacryloxypropyl silicone resins were prepared by a cohydrolysis condensation reaction with 3-methacryloxypropyltrimethoxysilane, methyl trimethoxy silane, and dimethyl diethoxy silane. The properties of the transparent resins cured by the ultraviolet were investigated in detail. The ultraviolet cured silicone material transparency was higher than 95% in the light wavenumber range of 400 nm and 800 nm, pencil hardness from 6 B to 6 H, and thermal decomposition temperature higher than 150°C. The silicone materials prepared by ultraviolet-assisted 3D printing had a water absorption coefficient of 0.21 wt% and a line thermal expansion coefficient of 5.27 × 10⁻⁴ m/k. It showed that the silicone resins can be candidates for ultraviolet cured transparent coating and ultraviolet-assisted 3D printing.”

A sol-gel method was used to synthesize the transparent silicone resins, which had various amounts of R/Si for UV-assisted 3D printing. These pre-polymer materials were 3D printed on an SLA 3D printer, and the resulting resins were deposited on slides and UV-cured.

The researchers measured the materials’ dynamic viscosity, along with the hardness of the cured samples and their apparent curing contents. They also recorded the transmittance spectra of the silicone resin pre-polymers cured on a slide, carried out thermogravimetric (TG) analysis of the 3D printed silicone resins, and performed differential scanning calorimetry (DSC) measurements of the final products.

By decreasing the n(R)/n(Si), the researchers found that they could increase the viscosity of the pre-polymers, as well as the pencil hardness of the UV-cured products.

Figure 4: The TGA curves for the silicone resins with various of n(R)/n(Si) cured by ultraviolet with 10 wt% of 2-hydroxy-2-methyl-phenyl-propane-1-one for 30 s.

“The TGA analysis (Fig. 4) showed that all the thermal decomposition temperature for the ultraviolet cured silicone materials higher than 150°C, which means that the cured silicone resins were all with fairly good thermal stability,” the researchers wrote.

The cured material is still sticky, with low hardness, if the amount of 2-hydroxy-2-methyl-phenyl-propane-1-one is less than 10 wt% of silicone resin pre-polymers – possibly because it wasn’t totally cured “for the insufficient amount of ultraviolet initiator.”

But, if the amount of UV initiator reached 10 wt%, absorption at 2333 cm⁻¹ and 1625 cm⁻¹ for methacryloxypropyl disappeared. Excessive amounts of UV photoinitiator will make the material’s properties worse, which is why the correct amount is 10 wt% of the silicone resin pre-polymer.

The researchers also investigated the influence of UV curing time, and found that when it was less than 30 seconds, the material would not completely cure. But, the cure time did not have much of an effect on the cured material’s gelation rate and hardness.

Figure 7: The FT-IR spectra for the silicone resin before and after cured by ultraviolet with 10 wt% of 2-hydroxy-2-methyl-phenyl-propane-1-one for 30 s.

“This phenomenon can be explained by the FT-IR analysis given by Fig. 7 that the characterization peaks at 1630 cm⁻¹assigned to the unsaturated double bond of the methacryloxypropyl almost vanished after the silicone resin cured by ultraviolet for 30 s, which demonstrated that the silicone resins were cured completely,” the researchers explained.

By observing the performance of the UV-cured silicone resins, it’s obvious that they can be used as transparent coating.

“Ultraviolet curable transparent acrylic modified resins were prepared by cohydrolysis condensation reaction with 3-methacryloxypropyltrimethoxysilane, methyl trimethoxy silane and dimethyl diethoxy silane. It showed that the prepared transparent acrylic modified resins can be cured completely cured by 10 wt% 2-hydroxy-2-methyl-phenyl-propane-1-one for 30 s with transmittance up to 95% in the light wavenumber range of 400 nm and 800 nm, pencil hardness from 6 B to 6 H, thermal decomposition temperature higher than 150°C,” the researchers concluded. “It also exhibited that the silicone resin prepolymers can be used for ultraviolet-assisted 3D printing. The silicone materials prepared by ultraviolet-assisted 3D printing are with coefficient 0.21 wt% and the line thermal expansion coefficient 5.27 × 10⁻⁴ m/k. It showed that the silicone resins can be a candidate material for ultraviolet cured transparent coating and ultraviolet-assisted 3D printing.”

Co-authors of the paper are Xiongfa Yang, Qiong Chen, Haoyuan Bao, Jiangling Liu, Yufei Wu, and Guoqiao Lai.

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A mishap has resulted in the first bioprinter to be sent to the International Space Station not quite making it to its destination. Last Thursday, the Russian spacecraft Soyuz MS-10 crashed due to a malfunction during liftoff. The bioprinter, called Organ.Aut, was to arrive at the ISS and be part of the first experiments in 3D printing organ tissue in space, but it was destroyed when the spacecraft malfunctioned.

“The bioprinter was in the habitation module, which jettisoned from the escape capsule of the Soyuz MS-10 spacecraft and fully burnt,” a source told Sputnik.

Two new members of the ISS crew, Russian cosmonaut Alexey Ovchinin and NASA astronaut Nick Hague, were also aboard the spacecraft, but they safely returned to Earth in a jettisoned escape capsule. The exact cause of the incident has not yet been announced, and is being investigated by a special commission of Russia’s space agency Roscosmos. All manned launches from Baikonur Cosmodrome have been suspended until the commission can figure out the cause of the failure. Incidents like this don’t happen every day – in fact, this was the first time in modern Russian history that a manned space launch failed.

So what happens next? 3D Bioprinting Solutions, the company that created the Organ.Aut 3D bioprinter, has a backup plan, as it turns out, and is now preparing to send a duplicate bioprinter into space.

“Organ.Aut and cosmonauts have a duplicate [of the printer], it will be ready to fly to the ISS in the near future,” said Yousef Hesuani, Co-Founder and Managing Partner of 3D Bioprinting Solutions. “We will work out a separate cycle graph of the experiment for preparing the flight at the Progress spacecraft. “The current crew has already confirmed its readiness for undergoing the remote training, so we will be ready to send the scientific equipment in any case.”

The delivery of the first 3D bioprinter to the International Space Station may have hit a snag, but it’s not really more than that: a snag. Besides the second bioprinter being provided by 3D Bioprinting Solutions, there are several other bioprinters being developed for the purposes of bioprinting in outer space. It may seem odd that so many are focused on bioprinting in space, when, after all, 3D printed organs are going to be needed here on Earth, but bioprinting is actually easier in zero gravity.

Thick, viscous liquids and large nozzles must be used to bioprint on Earth, but take away gravity and it’s possible to use much thinner inks and nozzles, allowing for much more precision. While some amazing bioprinting breakthroughs have happened here on Earth, there’s a whole world of possibility that may open up once we start using the technology in space. Advanced bioprinting has already taken place in zero gravity conditions, and another bioprinter is scheduled for delivery to the ISS early next year. Still another is set to go up shortly, as well.

The Allevi Zero-G is another space-bound bioprinter. [Image: Allevi]

It’s pretty much a certainty that bioprinting in outer space will be taking place very soon, and that we can expect to see some amazing developments once the printers actually start arriving on the ISS. The real question is which of them will start achieving those developments first.

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Last spring, we heard about an intriguing research project out of Germany’s Hasso-Plattner Institute (HPI), called TrussFab. The integrated, end-to-end 3D software system made it possible to design sturdy, large-scale structures, and then determine the proper distribution of recycled plastic bottles and 3D printed connectors to fabricate a strong end product, like a bridge, that could hold human weight.

While these structures were pretty interesting, they were static, as in non-moving. But HPI has completed a new research project, called TrussFormer, that builds on TrussFab and uses hinges and linear actuators to add movement to the structures.

This new software system lets users make large-scale, kinetic structures, which involve motion and dynamic forces, out of 3D printed hubs and recycled plastic bottles. The HPI team is presenting its new paper, titled “TrussFormer: 3D Printing Large Kinetic Structures,” at the Human Computer Interaction conference (UIST) in Berlin this week; co-authors are Robert Kovacs, Alexandra Ion, Pedro Lopes, Tim Oesterreich, Johannes Filter, Philip Otto, Tobias Arndt, Nico Ring, Melvin Witte, Anton Synytsia from Oregon State University, and Patrick Baudisch.

The abstract reads, “TrussFormer builds on TrussFab, from which it inherits the ability to create static large-scale truss structures from 3D printed connectors and PET bottles. TrussFormer adds movement to these structures by placing linear actuators into them: either manually, wrapped in reusable components called assets, or by demonstrating the intended movement. TrussFormer verifies that the resulting structure is mechanically sound and will withstand the dynamic forces resulting from the motion. To fabricate the design, TrussFormer generates the underlying hinge system that can be printed on standard desktop 3D printers. We demonstrate TrussFormer with several example objects, including a 6-legged walking robot and a 4m-tall animatronics dinosaur with 5 degrees of freedom.”

The system adds linear actuators into rigid truss structures, known as variable geometry trusses, to initiate organic movement, which means they hinge around several points at once. One example that illustrates this is a static tetrahedron that, when an edge is switched out with a linear actuator, becomes a moving structure. Rotation is possible by introducing connections, or hinges, at the nodes.

The research team demonstrated the TrussFormer workflow on an animatronic model of a T-rex. First, the software designs the static structure shape with structurally stable primitives, such as octahedra and tetrahedra. With TrussFormer, there are three different ways to animate the structures:

1. Automated placement
2. Placing elements with pre-defined motion; known as assets
3. Manual placement

The first way is for beginners, while the third is for users actively acquiring engineering knowledge. In order to add movement through the ‘demonstrate movement’ tool, the T-rex head is pulled down; then, the system places an actuator that turns the body into a structure capable of bending down.

TrussFormer then verifies that the mechanism is structurally sound during a stability check across the structure’s various poses, so that users don’t produce invalid configurations.

“In the background, TrussFormer finds the safe range of expansion and contraction of the placed actuator by simulating the occurring forces in a range of positions,” the researchers explained on their HPI project page. “If there is a pose where the forces exceed the pre-determined breaking limits or the structure would tip over, TrussFormer sets the limits for the actuator so it will not extend beyond them.”

Once the animation pane is opened in the software’s toolbar, sliders can be used to manually control and try out the structure’s movement. Once the desired pose is found, users can add it to the animation timeline as a keyframe. This allows TrussFormer users to orchestrate how all of the actuators move with just a simple timeline and editor: for instance, a feeding behavior, where the T-rex opens its mouth, leans down, and waves its tail, can be easily programmed.

Once the user has defined the structure’s animation, TrussFormer then computes the dynamic forces. In the example of the T-rex body moving up and down, the long neck’s large acceleration leads to high inertial forces, which goes past the construction’s breaking limit and causes the structure to fail. It can be hard to realize this ahead of time, because often times inertial forces are far higher than the static load in a structure. That’s why the software automatically corrects the animation sequence – limiting either the range of movement or acceleration – so that the structure will be able to hold up.

The ‘fabricate’ button is pushed once users are satisfied with the design’s structure, movement, and animation. This will then start the hinge generation algorithm, which analyzes the motion of the structure and generates the correct geometries for 3D printable hubs and hinges; these come with imprinted IDs for easy assembly. For the T-rex, 42 hubs, with 135 hinging pieces, are exported.

The software exports the animation patterns as Arduino code, and finally outputs a specification file with the speed, motion range, and force of the actuators so users can “achieve the desired animation pattern.”

“TrussFormer helps users in the 3 main steps along the design process,” the researchers conclude. “(1) It enables users to animate large truss structures by adding linear actuators to them. It offers three tools for this purpose: manual actuator placement, placement of assets performing predefined motion, and creating motion by demonstration. (2) TrussFormer validates the design in real time against static forces, static forces across all poses, and dynamic forces. (3) TrussFormer automatically generates the necessary 3D printable hinges for fabricating the structure. Its algorithm determines the placement and configuration of the hinges and their exact dimensions.”

VIDEO

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[Images: Hasso-Plattner Institute]

Daudi Barnes, right, works with lead analyst Mike Fitzpatrick, left, and lead design engineer Mesa Hollinbeck.

Colorado-based company Agile Space Propulsion was born from the expertise of Daudi Barnes, who has been working in the spacecraft propulsion industry since 1998. Agile Space Propulsion has a specific goal: to design and manufacture rocket engines using 3D printing technology. In particular, Barnes wants to develop thrusters, the small maneuvering engines used in rockets. According to Barnes, as rockets get cheaper, there is an increasing need for thrusters, and the miniaturization of electronics is spurring demand for more space vehicles for a variety of purposes.

“Cost reductions have opened up opportunities,” Barnes said. “People are saying: ‘Wow, if all of this is more affordable, we can do more missions now.'”

Rocket launches have been downsizing and becoming lighter and cheaper, partially thanks to 3D printing, which enables complex parts to be made in fewer components, or even in a single component. It also allows for a great deal of lightweighting.

“Weight is everything in space,” said Barnes. “It costs $1 million to put 1 kilo on the face of the moon. If you can make a spacecraft half a kilo lighter, you’re saving a ton of money.”

Agile Space Propulsion has already developed a 100-pound thruster and is currently working on a five-pound one. Barnes points to the use of 3D printing in much of aerospace, for both small and large engines.

“In traditional manufacturing, there are a lot of steps, a lot of parts, and there are restrictions on what you can do,” he said. “For instance, you can drill a straight hole, but you can’t drill a curved hole.”

3D printing, on the other hand, can create curved channels, and can cut down on the number of steps involved in making something like a thruster.

“The end product is more sophisticated, more capable and lighter, and that’s a really big thing,” said Barnes. “I can print in one day something that took months to make. Just the time savings alone is a big cost-saver.”

Barnes has already developed a prototype thruster for a lunar lander for NASA. The thruster had languished in production for years without making much progress, due to the limitations of conventional manufacturing techniques. Using 3D printing, Barnes was able to come up with a prototype in merely nine weeks, and it performed better than the engine that had been in production for so long.

Barnes is also the owner of Advanced Mobile Propulsion Test, which gives him access to that company’s rocket engine testing facility. This allows him to quickly iterate and test his designs.

“We use 3D printing, but the other part we have is the testing facility,” he said. “We can learn a lot when we test here. We’re uniquely diagnostic. We have very specific equipment that gives you detailed information and more certainty in the information you’re getting. We are also focused on a quick turnaround. You can get back to an engine, modify it and quickly retest.”

Barnes created Agile Space Propulsion because of a failure to land NASA grants to develop new technology, as Advanced Mobile Propulsion Test was viewed as a testing facility and not a design company. Currently self-financing the new company, Barnes is looking for $500,000 from investors. He also wants to hire a CEO to replace him so that he can focus on engineering and developing rockets. The company now has five full-time employees and three part-time employees, and works with several contractors.

Once he has completed business development, Barnes will seek an additional $5 million to enhance the company’s ability to produce thrusters.

“We’re sort of like a seed that’s planted, and we’re hoping it will take root and we will be able to grow it and sustain it,” he said.

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[Source/Images:

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3D Systems today announced the release of the ProJet MJP 2500 IC RealWax. This 3D printer is a digital foundry solution which lets existing investment casting operators switch to 3D printing for their patterns using MJP 3D printing. 3D Systems has implemented an entire investment casting solution along with the system including materials, machines, and software. By integrating software more workflows can also be automated and parts can be optimized. Injection molded tools are also not needed anymore. Overall 3D printing patterns should speed up the casting process. Traditional investment casting patterns are often laborious and require several manufacturing steps. 3D printing can reduce the number of steps taken to make a pattern and the overall cost. By using VisiJet M2 ICast the steps foundries have to take to adopt 3D printing are also comparatively facile. The VisiJet material is wax so it will work within the existing foundry and no updates and changes to furnaces or temperatures are needed to handle the material.

In commissioned research for one part, “cost comparison analysis conducted by Mueller Additive Manufacturing Solutions, a pattern tool for a mechanical cam cost $6,050 while the 3D printed equivalent pattern cost less than $25 – with the only lead time being the short time to print the pattern.”

Such calculations would be geometry and part size dependent of course but in general, we can say that by switching to 3D printing cost and time savings should be considerable.

Al Hinchey, 3D print manager, Invest Cast, Inc. stated that,

“We are able to produce parts that were previously not able to be produced using traditional wax injection molding. Additionally, the part quality, surface finish and accuracy have allowed us to move more of our production to this product. Finally, the complexity of parts that we can now produce has enabled new functionality that we can offer our customers,”

3DPrint.com interviewed Mike Stanicek, Vice President,  Product Management, Plastics, 3D Systems to find out more about this development.

If I’m a traditional investment casting company unfamiliar with 3D Printing what would I need to learn and what equipment would I need to implement this?

“The beauty of the ProJet MJP 2500 IC 3D printing solution is that it 3D prints patterns using wax. That means a typical foundry will have the experience and skills necessary to quickly adopt the workflow associated with the 2500 IC and transform their foundry. There is no need for the operator to learn new processes for building patterns onto trees, investing those patterns, melting out the wax or preheating of the investments. The printer is plug-and-play, and as one of our beta customers said “it was unboxed, set-up and printing in 5 hours.” The ProJet MJP 2500 IC comes installed with 3D Sprint™ software which simplifies the steps of turning geometry into a pattern that can be printed on the 2500 IC without the  need for an expensive 3D print preparation program. Finally, simple post-processing removes the support material that was generated during the printing process. 3D Systems provides detailed instructions regarding the steps and equipment to successfully carry out this process step. The operator can easily remove the majority of the support wax and then place the pattern in a heated IPA bath for about 30 minutes. After that, it is ready to be used to develop the casting shells.”

How can it decrease the cast parts weight?

“Design for additive techniques enable the optimization of a part in CAD so it is much lighter weight but would typically be regarded as ‘unmoldable’ using traditional pattern production. 3D printed casting patterns, however, can deliver that design optimization into the investment casting workflow because they are built layer by layer using the additive process. This gives flexibility to reduce the amount of material used while improving strength-to-weight ratios and makes these kinds of designs viable for casting.”

How will this let me save costs?

The ProJet MJP 2500 IC creates patterns in a fraction of the time and cost compared to
traditional pattern production.

1. By 3D printing the patterns, the time needed to design and fabricate a mold is
   eliminated. The traditional process typically takes weeks to accomplish. With the
   ProJet 2500 IC, first part can be achieved in hours or days.
2. The designer can try multiple design iterations without having to incur the expense
   of time and money to make each mold. This allows almost real-time design iteration.
3. Finally, the foundry does not need to account for tool storage. When a customer uses
   traditional molds, they must be stored until they are used again which necessitates
   an additional cost the foundry must incur. In a digital foundry, the mold is a digital
   file stored in a server room without maintenance, storage, or human capital cost.

Will this speed up my investment casting process?

“Yes, by removing the time to design and manufacture a mold, a foundry can reduce time to
first part by several weeks. This is a significant competitive advantage. For the foundry, this
can also help generate additional revenue as a premium, quick-turn service for customers.”

What post processing does the 3D Printed part need?

“With the ProJet MJP 2500 IC, post-processing is quite simple. Typical post-processing includes a manual “de-bulking” of the support wax which requires minimal effort as the wax is designed to be removed easily. Once that is complete, the wax pattern is soaked in a
heated IPA bath to remove any remaining support wax. The time in the bath is geometry-dependent but for most patterns, it will take 30 minutes or less.”

 Will this change buy to fly ratios for me?

“The ProJet MJP 2500 IC is already changing the way foundries operate, dramatically speeding time to first part and reducing overall total cost of operation (TCO). 3D Systems has developed a TCO model which shows the impact and breakeven analysis of typical wax pattern parts. While each part is different, the basic rule of thumb is 300 parts using 3 cubic inches of material or less will be cheaper to print than mold. In addition, by shaving weeks off the time to first part, additional savings result by achieving the first part faster without the expense and time required to build a traditional mold. A digital workflow enables foundries to achieve higher quality parts, and faster time to market while exploring.”