September 2019

46 n PRECISION MOTION September 2019 www.drivesncontrols.com ‘Revolutionary’ 3D printer turns to the UK for guidance I n 2015, an East German start-up called AIM3D set out to revolutionise 3D printing by creating a machine that would drastically reduce the cost of additive manufacturing of metal parts. The company’s founders, all from the University of Rostock, believed that additive manufacturing had so far failed to become widely used because of high material and machine costs. Even today, many 3D printers can only work with one material for printing and these materials are often expensive.“It was our ambition to create the machine tool for the 21st century that has a place in any company – much like a lathe or milling centre in the 19th century,” recalls Robert Radon, AIM3D’s head of mechatronics development. It took two years of r&d to achieve their aims, but AIM3D is now ready to move into serial production of its machine (which it calls the ExAM255) and is waiting for a patent to protect its CEM E-1 extruder printhead. The printer can work with almost any granulate material with diameters up to 3mm. It can handle pellets that are usually used for injection moulding, thus offering a wider range of materials than any other 3D printing technology. And the machine can print prototypes made of metals such as steel, as well as plastics, without costly retrofitting. “The really special thing about the extruder is that the customer does not have to purchase expensive polymer filaments or metal powders,” explains Radon. The ability to use standard injection granules makes the process much less expensive. In addition, the same material can be used for prototypes and for final manufacture, making the transition from prototype to finished product more economical and quicker. “In my opinion,”adds Rene Zielke, AIM3D’s head of plant development,“we are the only company so far to have developed such a universally employable 3D printer. Although there are a few that work with polymer granules, they do not offer choice in the range of materials and this is a unique feature of our system.” Two heads A notable feature of the new printer is the way it separates shape and fusion during the printing process. Only the thermoplastic carrier material is fused to give a component its shape. Following this, the component can be reworked before entering the sintering process. This, in turn, reduces tooling and machining costs during post- processing. The binding material is removed from the thermoplastic carrier in a two-stage process, and then sintered in an oven to create the final product. The printer uses two print heads to allow for possible material changes. During the printing process, the second print head is not used and has to be lifted constantly by 10mm to ensure that it does not collide with the object being printed. One unexpected challenge that the AIM3D team faced when developing their machine was finding a linear guidance system that would meet their needs. When they started to build their first prototypes, they were convinced that finding suitable linear guides would be straightforward – it did not seem a particularly complex task. However, it soon became apparent that this was not the case.“To A German company has developed a 3D printing machine that can work with of variety of metal and plastic materials, including injection moulding granules, thus making the printing process much cheaper. To provide the precision linear slides it needed for the machine, the developer turned to a UK supplier. AIM3D believes that its 3D printer is the first that produce components using standard injection-moulding granules.