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TRANSPORT & LOGISTICS
Additive Manufacturing Hub case study: Cobalt Design Cobalt Design made use of 3D printing to create small-scale models for the refurbishment of a railway carriage’s servery café, with support and assistance from AMTIL’s Additive Manufacturing Hub. Regional rolling stock across Australia and New Zealand is experiencing a surge in refurbishment programs aimed at extending the usable life of the interior spaces and amenities. Vehicle structure (as well as propulsion, braking and so on) are retained, while rejuvenating and refreshing the interior spaces as a means to upgrading the rolling stock or repurposing it for emerging markets, growing needs or new destinations.
The challenge The traditional method of refurbishing a carriage is to produce 2D CAD drawings and imagery to convey the approach, and to then rely on the experience of manufacturing personnel to implement the designs directly into the carriage at full scale. The process is timeconsuming due to a range of issues: • Components and brackets are often custom-made due to specific designs and low quantities. • Solutions often have to be compromised to be suitable for production requirements. • Feedback from stakeholders and management is only possible on a full-scale mock-up or an actual first-iteration 1:1 build. • Construction of structures in situ on rolling stock requires optimisation of subassemblies – minimising the number of subassemblies has advantages, but this must be balanced against the weight and size of the subassembly. Currently, this is typically managed ‘on the run’ during reviews of the first build or when a full-scale mock-up is built. Either approach is inefficient, and modifying full-scale structures and components extends development timelines. • Rolling stock depots that facilitate the build work often do not have the experience to move quickly through this process as it can be their first exposure to the vehicles being refurbished or to the refurbishment of interior spaces such as serveries (or both). Project Servo aimed to utilise additive manufacturing to create small-scale models of carriage interior spaces, components and equipment. This would enable stakeholders to communicate and evaluate different equipment alternatives within the space, as well as to test production methodologies and assembly sequences.
The solution Cobalt Design had been designing a servery café to be installed into a number of refurbished carriages. After the design concept was in development, Cobalt Design needed an effective method to communicate the design to the various project stakeholders, including production, maintenance, café staff and management. Cobalt Design engaged GoProto (ANZ) Pty Ltd to create 1:15 scale models of the interior space, major sub-assemblies and important components such as: • Bench workspaces. • Serving areas. • Storage cupboards and drawers. • Refrigerators. • Food display and warmer units. • Walls, door and structure. • Food cart and food cart storage options.
AMT OCT/NOV 2021
The Multi Jet Fusion (MJF) process was chosen as a reliable method to produce accurate models, with high durability, which would enable the servery to be disassembled and reassembled many times. This would be necessary to simulate the different configurations and assembly order options, and gain input by different stakeholders. Quick 3D CAD models were created for the main sub-assemblies, and components of the servery were simplified to approximately 15 robust units able to be pieced together in a Lego-esque manner. 3D CAD images were sent to GoProto for production of the MJF parts. Within three days, parts were completed for Cobalt Design to verify the scale models, before air-freight to a New Zealand-based customer. Therefore, within a fortnight of initiation, the servery concept and various options were being simulated for use and evaluated by team stakeholders.
How the Additive Manufacturing Hub helped Scale models proved an important tool in achieving approval of the servery design by different stakeholders, offering various advantages: • Scale models enabled physical evaluation of the space – not just virtual evaluation via computer. • Physical model parts allowed production staff to physically test the assembly order and methodology • Robust MJF parts allowed repeated assembly and disassembly, while evaluating and discussing alternatives
