MX3D + takenaka utilize robotic 3D printing to build a structural steel connector 

MX3D has teamed up with japanese construction company takenaka corporation to design and build a 3D printed structural steel connector. following the large-scale metal printers’ successful bridge project, MX3D’s latest work uses wire arc additive manufacturing (WAAM), showcasing the advancements in the production of highly customized and engineered steel joints.  

all images © leonard faustle (main video © claire bontje)

the structural steel connector is designed by MX3D and takenaka with the help of a topology optimization program that uses the mechanical properties of the printed material and the design constraints to generate guidelines on the most efficient shape. the joint has a hollow structure that is filled with concrete, poured post-print by takenaka engineers. filling concrete or mortar into steel tubes is commonly practiced in civil engineering as a more economical solution and is called CFST (concrete-filled steel tube). the inner concrete core prevents local buckling of the steel, while the outer steel bears bending and tensile forces.

the structural steel connector’s net weight is 40kg, reaching up to 45kg after its hollow core is filled with approximately 2.5 liters of mortar. MX3D has 3D printed this junction using duplex stainless steel, an alloy renowned for its good mechanical properties and excellent corrosion resistance, ideal for structural design. following the success of this initial concept, the partners involved now intend to implement the next bigger version(s) in an actual building project.

the goal of the project is to automate both the design and production of complex joints for large structures in the building industry. as the complexity of structures increases and skilled labor in countries with aging populations is less available such innovation is much required in the building industry. closing the digital design loop is another key focus point for the construction industry. the method used to produce this connector allows for full digital control over the design, production, timeline and cost with great logistic benefits and excellent integration with BIM applications.

the structural steel connector is printed using an advanced version of the MX3D proprietary technology. the company recently launched its metalxl software, a basic version of this technology that allows users to quickly start 3D printing large-scale metal objects in their own facilities. the beta 1.0 is currently being tested by selected users. beta 2.0 is available for pre-orders and expected in the first quarter of 2020. 

‘we’re getting much interest from construction companies after our moonshot project on the MX3D bridge. together with takenaka we’ve built this connector to show how the wire arc additive manufacturing (WAAM) technology is ready for industrialization to create unique connectors for complex constructions. this collaboration truly shows that architectural creativity doesn’t have to be limited by manufacturing constraints by further closing the digital design loop,’ says filippo gilardi, lead R&D engineering at MX3D.

‘this innovative manufacturing technology seamlessly connects bits and atoms, dramatically shortens lead times, pushes the boundaries of design, and finally contributes to the creation of more splendid architectural spaces. that is why takenaka collaborated with MX3D,’ comments takuya kinoshita, project leader at takenaka.

project info:

project team:

project development: filippo gilardi (MX3D) takuya kinoshita (takenaka)

MX3D engineering team:

process engineering: thomas van glabeke

engineering intern: michael jasinski

engineering intern: eddy bernou

production team: richard van dam, jean-francois moulin, cas nieuwland

takenaka engineering team:

design and engineering: ryo watada

structural engineering: fumiaki ohsuga

material engineering: yasuhiko inoue

production team: yusuke tanabe, daisuke honma, takaaki kurihara

special thanks to:

video: claire bontje

photography: leonard faustle

designboom has received this project from our ‘DIY submissions‘ feature, where we welcome our readers to submit their own work for publication. see more project submissions from our readers here.