U.S. Marines with 3rd Marine Logistics Group 3D printed a replacement part for a U.S. Coast Guard boat in South Korea on July 11, 2026 during the Combined Joint Logistics Over-the-Shore (CJLOTS) 26 exercise, turning a repair that would normally take two to three weeks into a same-day fix that cost about $12.
The part, printed by Marines with 3rd Maintenance Battalion, Combat Logistics Regiment 35, matched the price of the original component, after the unit reverse-engineered the piece and printed it inside an Expeditionary Fabrication Facility (X-FAB), the Corps’ containerized, deployable 3D printing lab.
A Broken Boat, a Missing Part, and a Same-Day Fix
CJLOTS is a recurring U.S.-Republic of Korea exercise that trains forces in moving personnel and equipment from ship to shore in austere conditions. During this year’s iteration, a Coast Guard watercraft needed a specific part that wasn’t available through standard supply channels, the kind of gap the Corps’ additive manufacturing push has spent nearly a decade trying to close.
“There is a demand to decrease the supply deficiencies and backorders in order to increase repairs and replenish items quickly,” said Chief Warrant Officer 2 Jonathan B. Salas, utilities officer for Regional Maintenance Operations Company North, 3rd Maintenance Battalion. “In this case, we cut a potential two- to three-week shipping delay for a replacement part down to just a few hours.”
Marines scanned and reverse-engineered the original component in their design systems, made minor adjustments, and printed a functional replacement that was installed and returned the boat to service. Salas noted the unit also has the option of switching to a cheaper filament that would trim another $4 off the part’s cost without affecting performance.
The fix kept the Coast Guard’s rigid-hull inflatable boats, valued at roughly $600,000 each, available for quick-reaction-force and patrol missions securing the waters around the exercise.
“They were taken aback by the fact that a part such as their strainer can be reverse-engineered and 3D printed in full in less than half a day,” said Cpl. Kenzie Gallang, a metal worker with the battalion.
The Lab Behind the Fix
The work was done out of an X-FAB, a self-contained expeditionary fabrication laboratory the Marine Corps began evaluating in 2017 as a tool for on-demand crisis response. At the time, the 20-by-20-foot shelter was stocked with four 3D printers, CAD software, and a 3D scanner, and a team of four Marines could set it up on-site in two to three hours.
“In a contested environment where ships cannot easily land, or airplanes cannot necessarily fly in and deliver goods, Marines need a way to support themselves, at least temporarily,” Lt. Col. Howie Marotto, additive manufacturing lead at Marine Corps Installations and Logistics, said during the lab’s early field evaluation. “The deployable X-FAB would give them another outlet to supply themselves until the regular logistics or supply chain can support them.”
The capability was framed from the outset as a way to shrink the same kind of supply-chain wait 3rd MLG’s Marines cut through in Pohang. “Instead of waiting weeks or a month for a part, our machinists can get the part out by the end of the day,” said Master Sgt. Carlos Lemus, who helped run the lab’s initial field evaluation.
The Marine Corps has also used the platform to equip units with new technologies like 3D printed drones, part of a wider Department of Defense push to fund additive manufacturing across the services. The plan has been to eventually pair X-FAB with the Corps’ Shop Equipment, Machine Shop (SEMS) milling capability for a more complete field-repair setup. Also part of the Marines X-Fab system are Markforged Mark Two 3D printers.
Bilateral Payoff for the ROK-U.S. Alliance
Beyond the single repaired boat, the episode is being framed by 3rd MLG leadership as a proof point for combined logistics resilience on the Korean Peninsula. Producing components on-site, rather than routing every request through traditional supply nodes, gives allied forces a way to sustain equipment readiness in the field and share fabrication solutions across services and nations.
“We are demonstrating how nontraditional manufacturing methods, even in an expeditionary environment, can produce parts of consequence to improve the readiness across the joint force,” said Col. Robert Fairley, commanding officer of Combat Logistics Regiment 35.
The Corps has framed this kind of tactical-level sustainment as central to CJLOTS 26’s broader goal of strengthening U.S.-ROK interoperability, with the expectation that validated 3D printing workflows can be extended to future joint and combined exercises.
Closing the Contested-Logistics Gap
The CJLOTS fix fits into a broader defense strategy of pushing manufacturing capability to the point of need rather than relying on long, vulnerable supply lines.
Other services have chased the same gap with different hardware. The U.S. Army has leaned on metal cold-spray printing for exactly this problem: at a Tennessee training range, SPEE3D’s deployable Expeditionary Manufacturing Unit produced a mission-critical vehicle part in under ten hours and delivered it by drone, compressing a six-to-ten-week standard logistics timeline into a single operational day. SPEE3D CEO Byron Kennedy framed the stakes bluntly: waiting weeks for a part isn’t just a delay, it’s a tactical vulnerability.
The Army has pursued the same logic on the materials side. Its Combat Capabilities Development Command 3D printed AF96 steel impeller fans for the M1 Abrams tank engine as a proof of concept for reducing convoy loads of spare parts, the idea being that raw material and a printer can substitute for truckloads of pre-positioned inventory, provided the printed parts can be qualified against OEM performance standards.
Across services, the throughline is the same: shrink the distance between breakdown and repair, and shrink the convoy that repair used to require. The Marines’ $12 Coast Guard part is a small-scale instance of a strategy the whole Department of Defense is now scaling up.
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Featured image shows U.S Marines with 3d Marine Logistics Group showcase 3D Printing Capabilities to the U.S. Coast Guard at CJLOTS 26. Photo via Lance Cpl. Marcus Henson, 3rd Marine Logistics Group.
