US Navy Tests At-Sea Metal 3D Printing for the First Time at RIMPAC 2026

A US joint military team deployed a cold spray metal 3D printer aboard the Canadian support vessel MV Asterix during RIMPAC 2026, marking the first time the technology has been used at sea during a live naval exercise. The test showed that warships could produce mission-critical replacement parts while underway, without waiting for a resupply convoy to reach them.

The work was led by the Consortium for Advanced Manufacturing Research and Education at the Naval Postgraduate School, with support from the US Army Combat Capability Development Command Army Research Laboratory, the Tennessee Army National Guard, and the University of Tennessee Knoxville. SPEE3D, an Australian additive manufacturing company, provided the hardware.

How the System Worked

The SPEE3D Expeditionary Manufacturing Unit combines a containerized XSPEE3D cold spray printer with an integrated SPEE3Dcell post-processing and machining system. Cold spray additive manufacturing deposits metal powder at supersonic speeds, building dense parts without ever melting the material. That matters at sea: no high-temperature furnace, no special ventilation, no risk to the ship from extreme heat.

During the exercise, the team produced 32 metal parts across a manufacturing network that spanned ship and shore. Twenty-four parts came through a reachback connection at the Knoxville Armory. Eight were built directly aboard the MV Asterix using the at-sea printer. Twenty-nine of the 32 parts reached full completion, including heat treatment and machining.

Why Point-of-Need Manufacturing Matters for the Navy

Naval supply chains are slow and vulnerable. A ship operating in the Pacific or the Mediterranean can be weeks away from the nearest depot carrying the right spare part. A broken pump housing, bracket, or valve can sideline a mission. The RIMPAC test was designed to answer a simple question: can you print a usable metal part on the flight deck of a ship in rough seas?

The answer appears to be yes. SPEE3D CEO Byron Kennedy described the deployment as printing metal parts "on an open deck in heavy seas aboard the MV Asterix, alongside the US Navy and the Royal Canadian Navy." The system had already been tested on land during RIMPAC's Trident Warrior 24 in 2024, where it produced 11 cast-equivalent metal parts at Kaneohe Bay, Hawaii. A separate test in 2023 demonstrated cold spray printing in sub-zero temperatures at the US Army's Cold Regions Research and Engineering Laboratory. Each environment tested a different constraint. At-sea operations under way were the final frontier for the platform.

From Prototype to Operational Reality

The RIMPAC 2026 deployment was not a one-off technology showcase. CAMRE deployed more than 50 advanced manufacturing systems during the exercise, with the SPEE3D unit treated as an integrated node in a broader coalition manufacturing network. Morgan Bower, FLEETWERX Hub Director, framed the test in terms of coalition interoperability: "Producing parts at sea on NATO vessels using coalition equipment is an example of the flexibility and interoperability that are key to modern operations."

Lt. Col. Chris Curran, USMC (Ret.), Program Manager at CAMRE NPS, put it more directly: "The ability to produce, post-process, and evaluate parts while operating at sea has direct implications for readiness and sustainment."

The parts themselves were functional replacements, not prototypes. The eight at-sea prints included aluminum bronze hatch hardware. Heat treatment and machining were completed without the printer leaving the ship. Twenty-nine of 32 total parts across the network reached full completion, a roughly 91% success rate in an environment that included open-ocean conditions, coalition coordination, and the logistical complexity of a 30-nation exercise.

Cold Spray vs. Traditional Metal 3D Printing

Cold spray additive manufacturing is different from the laser powder bed fusion systems most people associate with metal 3D printing. There is no laser, no melt pool, no need for inert gas shielding around a heated build chamber. Metal powder is fired through a nozzle at supersonic velocity, bonding to the substrate on impact. The process is fast, works with standard alloys like aluminum, stainless steel, and copper, and produces parts that are near-net-shape with good mechanical properties. The tradeoff is lower resolution compared to powder bed systems, but for functional replacement parts, tolerances are often acceptable as-printed or after light machining.

SPEE3D's Expeditionary Manufacturing Unit was designed with that use case in mind. The printer is containerized, transportable by standard military logistics, and can be set up without specialized infrastructure. The integrated SPEE3Dcell performs heat treatment and CNC machining in the same footprint, which means a part can move from digital file to finished component without leaving the ship.

What Comes Next

The RIMPAC results feed into broader Pentagon efforts to scale additive manufacturing across the submarine enterprise and the naval surface fleet. The Navy has already signaled interest in point-of-need manufacturing for forward-deployed units, and this test gives concrete performance data to justify further investment. SPEE3D's track record now includes sub-zero, tropical, battle-damage, and at-sea conditions. Each environment has produced completed parts. The company's argument is that additive manufacturing works where conventional supply chains break down. RIMPAC 2026 gave that argument its strongest evidence yet.