Songdo RM2 Sculpture

This project involved fabricating sculptures for an apartment complex in Incheon. To produce the tallest free-form piece, at approximately 3.5 m, we applied a metal 3D printing technique based on automated robotic welding.

WAAM uses arc welding, in which metal wire is fed together with an inert shielding gas (argon), to deposit molten metal continuously onto a substrate. Building up layer upon layer of weld beads, we 3D printed the sculpture in stainless steel — a process similar to FFF (fused filament fabrication) 3D printing, in which plastic is melted and deposited in layers.

Before production, we ran stainless steel deposition tests with WAAM to determine suitable deposition parameters (travel speed, wire feed speed, current/voltage, bead width and layer height), and prepared robot-controlled plasma cutting equipment for cutting after deposition.

The arc welding equipment was synchronized with the industrial robot's motion. We programmed motions that tilt the torch-mounting flange to match the inclined geometry of the sculpture, so that the molten metal stays in place instead of running during welding.