3D printed boats are no longer prototypes — they’re operational hulls built layer by layer using large-format additive manufacturing. Unlike traditional boatbuilding (fiberglass layup, aluminum welding, or molded composites), large-scale 3D printing fabricates the hull directly from a digital model using thermoplastic extrusion. Most marine projects use materials such as reinforced PLA, PETG, ABS, or recycled polymers, sometimes blended with glass or carbon fiber for improved stiffness and impact resistance. Here’s what makes it technically interesting: • Layer-by-layer fabrication enables complex internal ribbing and lattice reinforcement without additional molds • Variable wall thickness can be printed directly into the hull design • Rapid prototyping reduces tooling time and cost • Digital models allow iterative hydrodynamic optimization before fabrication • Potential for on-demand, localized manufacturing Hydrodynamics still matters. The printed hull must manage buoyancy, drag,...