Going from CAD file to additive manufacturing file is not quite as easy as it could be. But researchers are getting closer to developing the right functions that translate CAD data to useful 3D printing data.
For example, International TechneGroup Limited (ITI) reports the successful conclusion of an EU additive manufacturing (AM) initiative where new developments in CADfix, ITI’s advanced geometry processing software, delivered key breakthroughs in AM geometry handling. The goal of the EU initiative, known as “Hyproline,” was to build a working demonstration of a high performance AM production line for small series metal parts.
The Hyproline platform promises to enhance the competitive position of Europe’s small and medium-sized enterprises (SMEs). Program researchers focused on three different metals: stainless steel 316L, titanium and copper and serial production of custom parts on the order of 10 mm with a goal of 10,000 parts per day. Challenges included increasing the quality of 3D printed metallic parts, an area where CADfix contributed through improved slice generation from CAD, and processing of inline 3D scanning and laser ablation with real-time point cloud capture and 3D comparison, culminating in the generation of custom laser tool-paths for use by a continuously running production line.
“The concept was initially focused on SMEs in the electronics and aerospace industries, but has potential application in other industries that produce low volume, high precision metal parts,” stated Frits Feenstra, senior project manager, TNO. “We are excited about further developing this manufacturing platform to enable fully integrated mass production of custom 3D printed products.”
AM is maturing but improvements in accuracy of 3D geometry and CAD files, and improvements in post-processing, are critical for reducing costs, reducing production times and increasing quality and reliability. Managing the data flow for scanning geometries with high precision and processing that information fast enough to allow the AM process to become adaptive is becoming a key issue in driving the wider adoption of AM.
ITI’s CADfix translation, repair and defeaturing solution was used to prepare CAD geometry for the additive manufacturing step for Hyproline, to convert the point cloud to the 3D surface and to compare the as-produced 3D object with the CAD model while on the production line, and finally to generate tool paths to drive the laser ablation stage of the production line.
“CADfix is suitable for this type of additive manufacturing because of its flexible, closely linked representations of geometry, ranging from continuous CAD geometry to discrete facetted geometry, such as facets, slices or point clouds. Access to multiple forms of geometry enables CADfix to be applied effectively to all aspects of the AM geometry process chain. For the Hyproline platform, CADfix was comparing the point cloud scans to the as-designed CAD to extract the excess material to be removed by the laser processing stage,” said Mark Gammon, ITI. “This endeavor was truly ground-breaking because of the high-speed of laser polishing of the metal parts, combined with 3D scanning to produce multiple, unique parts in the same run, on the same production line.”
This consortium began as a result of an EU FP7 Factories of the Future Program grant awarded in fall 2012. Formal consortium work concluded in August of 2015. Primary objectives were to reduce time-to-market, to reduce waste, and to reduce the number of rejects.
