Automated post-print processing on 3D printed parts
Third Quarter 2019, Electrical switching & drive systems & components
Additive manufacturing processes can produce parts with the most complex geometries in a single operation. However, post-processing these 3D printed parts is time consuming and costly. In order to remove this bottleneck in the production process, PostProcess Technologies has developed a series of machines that leverage a groundbreaking chemistry of detergents and abrasive media. The newest example is the Hybrid DECI Duo. The multi-functional machine provides automated removal of support material and surface finishing. It was automated with control technology from Beckhoff.
Image copyright PostProcess Technologies, USA.
The challenges of post-print processing in additive manufacturing include surface finishing and the removal of support material. Particularly when building complex structures, any overhangs or other asymmetrical contours require the use of support materials. These ensure that the workpiece does not collapse during production and maintain the correct shape of the part during printing. The support materials must be removed afterward. In addition, the parts printed from materials such as advanced thermoplastics, light-cured resins and metals often require finishing to achieve the desired look and feel while meeting requirements for size, texture and precision.
PostProcess Technologies was founded in 2013 with a vision to revolutionise additive manufacturing by removing the post-print bottleneck, thus paving the way for economical series production. The company developed a completely new process that leverages a groundbreaking chemistry of detergents and abrasives as well as pressure and temperature instead of using cutting tools.
The core of the PostProcess solution is the proprietary Automat3D software, which, guided by the company’s Agitation Algorithms (AGA), facilitates different agitation or intensity levels in post-print processing. By individually adapting the process parameters, the solution can meet the requirements of even the most varied part geometries without destroying important structures.
As PostProcess began to implement its machines, the company knew it needed proven, robust automation components. Since most of the 3D printers are not PLC driven, but rather PC driven, they decided to use PC-based control technology from Beckhoff. PostProcess has developed a range of different machines for removing support materials or surface finishing. The newest addition to their product offering is the Hybrid DECI Duo, the first multi-functioning machine that combines both processes in a single compact system that helps optimise valuable production floor space.
“A PC-based platform that combines Windows OS and automation tools based in Visual Studio was an ideal fit for our programming efforts, given that we are not specifically controls engineers, but lean more toward computer science,” says PostProcess president and CTO, Daniel Hutchinson. “This convergence of automation technology and information technology driven by Beckhoff enables us to have greater flexibility with our workforce, drawing from many different pools of engineering talent.”
TwinCAT 3 PLC and NC/PTP serves as the back-end for the DECI Duo system, providing real-time automation of the part processing operations. PostProcess has also standardised on a motion system from Beckhoff, consisting of AM8000 series servomotors with One Cable Technology (OCT) and several AX5100 EtherCAT servo drives. Hutchinson continues: “The AM8000 series motors fit our needs perfectly. Compact size and minimised cabling were at the top of our list of requirements, and these motors hit all the right marks. Plus, the combination of the OCT motors, servo drives and EtherCAT as the drives bus made commissioning very simple.”
Hutchinson explains the benefits of EtherCAT as system bus for the Hybrid DECI Duo: “EtherCAT is our sole communication protocol for all of the PostProcess Production series machines. The microsecond-level communication speeds are unparalleled. EtherCAT also supports flexible topologies and the use of third-party hardware.”
EtherCAT I/O terminals are installed across all PostProcess Production lines. According to Hutchinson, this provides maximum flexibility and streamlines future expansion. Reduction in development time was the most important benefit realised by PostProcess. “With the Beckhoff system, our development time was cut in half,” reports Marc Farfaglia, engineering manager. “Much of this is due to the flexibility of TwinCAT 3 software and the ability to reuse function blocks and other code on subsequent machines.”
TwinCAT also provides further benefits for engineering, as it pairs very well with the Automat3D software. Hutchinson concludes: “The ability to utilise industry standard development tools and configuration management services, such as Microsoft Visual Studio, Visual StudioTeam Services and third-party extensions, greatly improves the development time, organisation and learning curve for our developers. As the 3D printing and additive manufacturing market continues to evolve at a rapid clip, it is exactly this level of flexibility that will help OEMs like PostProcess shape the future of the industry.”
For more information contact Michelle Murphy, Beckhoff Automation, +27 11 795 2898, email@example.com, www.beckhoff.co.za