Marshall Aerospace and Defence Group, which is one of the world’s largest privately owned and independent aerospace and defense companies, has invested in a 3D printer from Stratasys to manufacture flight-ready parts for several of its military, civil and business aircraft as well as producing specific ground-running equipment at a lower cost than aluminium alternatives.
Marshall ADG is a British company, headquartered in Cambridge, UK, but with facilities in Europe and North America. The company was set up in 1909 and first became involved in aviation back in 1912 when its mechanics helped repair a British army Beta II airship that had made a forced landing with engine problems behind Marshall’s garage in Cambridge. Today the company employs some 1800 staff, and supports 16 air forces around the world, including the RAF.
Marshall uses a Fortus 450mc FDM printer together with Stratasys’ Ultem 9085 resin. Chris Botting, Materials, Processes and Additive Manufacturing Engineer at Marshall ADG,describes this as a lightweight material with high thermal and chemical resistance, noting: “This has been crucial to overcoming the stringent requirements of our industry, as we can now 3D print parts with the desired flame, smoke and toxicity properties for use on aircraft interiors.”
He adds: “When manufacturing on complex engineering programs, we need a method that can create an accurate, complex, functional and lightweight duct efficiently with minimal tooling costs – this is where 3D printing fits perfectly. But we also need to ensure that the ducting work produced will be approved by the EASA for flight.”
Part of Marshall’s core capabilities is to heavily modify aircraft to suit particular roles. The company already has several pieces of 3D-printed ductwork flying on these aircraft, as well as holders for safety knives and switches for aircraft interiors. It uses 3D printing to produce parts on-demand that are lighter and cheaper to produce than would be the case with traditional methods. Botting says that the ability to create accurate, repeatable and reliable 3D printed parts using aerospace-approved materials are key factors in achieving the performance requirements necessary for use within aircraft.
Marshall also 3D prints parts for ground use, such as a ducting adapter prototype for ground-based equipment that provides fresh air to cool an aircraft’s avionics. In this case, 3D printing helped Marshall transition from typically costly aluminium processes.
Botting explains: “It enabled us to create an accurate working prototype of a complex component. We were then able to demonstrate it had the potential to be 3D printed in Nylon 12 material as opposed to the more conventional method of machining from aluminum. The 3D printed duct led to a significant cost reduction compared to machining the part out of aluminum, as well as a 63% reduction in overall weight.”
Marshall ADG also 3D prints a range of complex tooling applications, including drill jigs, masking templates, bonded fixtures and composite mold tooling. The team regularly produces customized, low-volume production tools within just 24 hours of an engineer’s request. The aim is to replace heavy metal tools with 3D-printed thermoplastic tools to cut costs and lead times on urgent operational tasks.
Botting comments: “FDM technology has altered the way we work, and the aerospace-grade 3D printers and materials enable us to meet our increasingly aggressive deadlines and complex manufacturing requirements.”
He concludes: “In the future, there is no doubt that 3D printing will continue to have a significant impact in the way we design and manufacture in our business.”