The biggest, the smallest, micro or massive. While many announcements pride in this or that title, one thing is clear, Additive Manufacturing (AM) comes in (almost) all scales and sizes. Just as AM isn’t limited to one technology, the results can’t be limited in size, each additive technology can reach different results, characteristics and caters to a different need or industry. Here are a few recent examples to gauge the scope of AM.
Size is Relative
Tiny is a relative term, a tiny home, for example, is not so tiny (above tiny home 3D printed by ICON). On the other hand, the rocket piece below might be smaller than a home but it is one of the larger 3D printed parts that was printed in one piece for aerospace purposes. Size is also relative in regards to materials and technologies, the BAAM 200 at ORNL is capable of printing components up to approximately 6 meters long by 2.5 wide and 1.8 meters tall (second below is a one-piece tool produced for Boeing). BAAM (Big Area Additive Manufacturing) uses polymer materials, when it comes to metal 3D printers sizes are usually smaller and the printable area is measured in millimeters or centimeters, one example is the A.T.L.A.S project by GE’s and Concept Laser.
A Room Size Bed
There are impressively big machines, yet there are some that go beyond the limits of the machines’ bed size. Thermwood for example, 3D printed a 6 meters long helicopter blade mold for Bell (above). The company also has a solution for longer prints, where the printed piece is built sideways while printing instead of upwards. In other cases, especially when it comes to construction the machine is a free-standing robotic arm. The robotic arm serves as a giant extruder and while the advantage is it can move much more freely through space its resolution level is usually less than refined. Still, even though the surface isn’t smooth the results such as the MX3D bridge are structurally sound (below and in video). Of course, post-processing can be applied, bringing the piece to the desired finish. In the manufacturing of large items post-processing such as subtractive machining is still less wasteful than using subtractive manufacturing as the main method and machining the part entirely.
It’s in the Details
While in large prints resolution isn’t necessarily a high priority, when it comes to smaller parts it’s not just about the overall size of the object, the resolution is equally important. Nanofabrica makes micron-level resolution industrial 3D printers. They use a patented process based on Digital Light Processing (DLP) engine, and Adaptive Optics (AO), which improves image distortions in optical devices. Their process is used to manufacture industrial grade parts (up top and below) which are just a few millimeters big (or small) with wall thickness of approximately 0.02 millimeters, and each print layer is 0.002 millimeters thick (or thin). Another company in the nano-sphere is Nanoscribe which uses AM for serial production of microcomponents, micro-optics, and filigree structures. Recently Nanoscribe joined MiLiQuant, an initiative aimed at developing diode laser-based light sources alongside companies such as Bosch and Zeiss.
Measuring in Micrometers
When it comes to parts that are as small as the parts mentioned above, the dimensions are described in micromillimeters or microns which are one-thousandth of a millimeter (0.001mm = 1 μm). Just to make things a bit more visual, the length of a typical bacteria is 1–10 μm, plastic wrap is about 10–12 μm, so 5 or 6 times thicker than the Nanofabrica print layer mentioned above. This scale is relevant for the medical industry, implants such as the Matrixx series by Nexxt Spine printed on GE machines, for example (below). In implants, the intricate porous structure is said to help the healing process and the rejuvenation of tissue around it. Alaedeen Abu-Mulaweh, director of engineering at Nexxt Spine explains the chosen geometry in their implants: “Titanium – porous or otherwise – is physically incapable of biological remodeling, so using additive to directly mimic the structural randomness of bone doesn’t make a whole lot of sense. Rather than simply looking like bone, Nexxt Matrixx® was designed with functionality in mind to fulfill our vision of actively facilitating the body’s natural power of cellular healing.” The whole implant is only a few millimeters in size, making the inner walls of the structure micron-scale.
Size, of course, isn’t the main point, it’s just a reflection of the applications and demands across industries and scales. What are your thoughts? Do the titles “biggest” or “smallest” really matter? Tell us in the comments below. For more insights and information follow us on LinkedIn or subscribe to our newsletter for weekly updates.