3D printing has come a long way since its invention back in the 1980s. The clunky mechanical components of old have been substituted out for refined, slick, and precision machined parts that enable additive manufacturing on a scale never seen before. Regardless, the throughput of the technology is still far behind that of conventional manufacturing techniques, but this is slowly changing.
To keep up with an ongoing rise in global demand, the speed at which 3D printers can produce parts has increased drastically, and specialist OEMs and researchers alike are constantly pushing the boundaries of what is possible, both in terms of hardware and software.
Leading the charge with VAT Photopolymerization
Without a doubt, the fastest sub-technology within 3D printing is VAT Photopolymerization (VP). Digital Light Processing (DLP) and Liquid Crystal Display (LCD) systems use visible light and UV light respectively to cure photopolymer resins into solid 3D shapes, one layer at a time. The simple fact that entire layers can be cured in one go, often in less than around 7 seconds, makes VP synonymous with rapid 3D printing.
Leading in the market space, In-Vision, an Austrian developer of high-precision optical systems, recently launched its most powerful 3D printing light engine to date. With over two years of research and development going into it, HELIOS is a UV light projector designed specifically for resin-based 3D printers. The company claims its engine can achieve the highest illumination intensity in the market space, enabling faster cure times and compatibility with a greater number of resin types.
To put it into numbers, the engine has the power to deliver up to 60W of illumination intensity, which is around double the current industry standard. This kind of power simply wasn’t around when VP inventor Chuck Hall first worked with the technology in the early 80s.
Over in the academic space, researchers from Northwestern University’s McCormick School of Engineering recently developed a novel VP 3D printer that is capable of printing up to 2000 layers a minute. Again, the impressive print speed can be attributed to a high-power light engine, which helps to cure resin at a much faster rate.
Interestingly, the system makes use of a six-axis robotic arm - this is something you might see employed by an industrial DED 3D printer or conventional assembly line - rather than the more common Z-axis rail that most other resin printers operate on. By providing the freedom to move, rotate, and rescale each layer as it is being printed, the system also grants a whole new level of design freedom.
Advances in Fused Deposition Modelling
Fused deposition modeling, or FDM, is the most common 3D printing technology out there, but it's nowhere near as fast as resin technology. This is owing to the fact that the nozzle must scan out the entire volume of a 3D printed part to fill in the shape, rather than just flashing entire layers in one fell swoop. Without the option to use a more powerful light engine, FDM engineers are forced to be a little more creative to boost their print speeds.
Taking a fairly unorthodox approach, a company called Ulendo uses software algorithms to increase print speeds on third-party FDM printers. In fact, the company’s technology recently won a $250,000 research and development grant from the National Science Foundation’s America’s Seed Fund Program.
The software goes by the name of Ulendo FBS, and it works by modifying an FDM 3D printer’s firmware to improve print speeds by up to 100%, all without sacrificing the quality of the part being produced. The program addresses an issue that has plagued desktop printers for as long as there have been desktop printers - vibrations.
Many of the desktop systems on the market today still need to operate at relatively slow print speeds to dampen the vibrations caused by their moving parts. For reference, a typical print speed is around 60mm/s. Print too fast, and you run the risk of part defects and misaligned layer lines, where the printer’s frame has shook itself excessively.
At the heart of Ulendo FBS is a vibration compensation algorithm developed to counteract these unwanted vibrations experienced by a moving 3D printer’s frame. The program anticipates when the printer may be about to experience a disruptive vibration and dynamically adjusts its motion accordingly with predictive control models. So, even though FDM technology may be reaching its limits in terms of hardware, the ingenuity of software such as Ulendo FBS can still squeeze out a little more performance.
Taking it to the next level
The examples covered above are by no means extensive, but they act as proof that decades on, there are still innovations in both the hardware and software realms that push the performance of the technology to new heights. As is human nature, engineers and designers will constantly look for the next best thing, whether that be higher power lasers, improved light engines, or more robust mechanical frames.
Ultimately, 3D printing speeds still have a while to go before they can match the throughput of conventional manufacturing technologies such as injection molding and subtractive machining, but that’s not to say they’re not getting there day-by-day.