Boeing, the Manufacturing and Industrial Technology Divison (ManTech), NavAir Aermip and Thermwood collaborate on large scale composite AM cure tool.
Boeing’s Research and Technology department submitted a proposal to look into the development of low cost composite cure tooling technology.
Thermwood’s Large Scale Additive Manufacturing (LSAM) system was chosen due to its capabilities to 3D print very large components and the results of work already carried out. Thermwood previously collaborated with the U.S. Navy to produce the nose of one of their submarines as well as being involved in previous research and development collaborations with ManTech.
Neil Graf Office of Naval Research, noted “Composite manufacturing is a strategic technology for future platforms, development of more cost effective tooling solutions would (be of) significant benefit.”
The highly contoured mould was the most challenging shape that the LSAM had worked with. The spherically shaped portion of the mould line offered the largest challenge, as the unsupported 3D printed angle limitation of approximately 45 degrees provides an interesting obstacle to overcome. Boeing rotated the 3D print plane 35 degrees to avoid encroachment of the build angle limitation.
The final 3D Print Model
TechmerPM PESU CF 1810 high temperature print material was used to create the composite cure tool. High temperature materials present additional challenges during print over low temperature materials. Two interim support features were added to compensate for the centre of gravity shift of the print. The LSAM machine performed flawlessly during the composite cure tool print. The tool was printed in 7 hours and 26 minutes using 610lbs of material.
After machining the tool was tested by the Boeing Research and Development Team for surface profile, dimensional stability and vacuum integrity. The LSAM printed tool passed all tests and achieved dimensional surface profile tolerances of .020” (+/-.010”). Further tests of the tools durability were then carried out during multiple autoclave cure cycles and fabricated three parts. The tool achieved all parameters including vacuum integrity throughout.
The cost savings were estimated at 50% compared to traditional manufacturing methods and reduced the lead time by 65%. These savings as well as the environmental impact of less material wastage could provide huge benefits to any organisation who are looking to fabricate bespoke or low volume components.
“Collaborations such as this help expand the scope of capabilities of emerging large scale additive technology by addressing real world challenges that would be difficult for any single entity to define and address by itself. We look forward to new challenges moving forward”, says Thermwood CEO, Ken Susnjara.
Thermwood is looking forward to future collaborations and the opportunity to show case enormous benefits that large scale additive manufacturing can have.