Engineers at Naval Surface Warfare Center (NSWC) Corona have designed a 3D printable part for one of the most dangerous jobs in uniform. According to VoxelMatters' November 8 report, the Submunition Clip gives explosive ordnance disposal (EOD) teams a mechanical way to hold the firing pin of an unexploded submunition in place. It replaces the epoxy and plaster that technicians have used for the same job. The design earned its team a Naval Sea Systems Command (NAVSEA) Excellence in Safety Award for fiscal year 2025. A provisional patent has been filed with the U.S. Patent and Trademark Office. And the designer wants the part to reach the field the way makers share parts with each other: as a file that units download and print themselves.
A note on sourcing: the Navy's own announcement page couldn't be read when this story was prepared. Everything below comes from the VoxelMatters and Interesting Engineering reports, both linked at the end.
The Problem: Holding Still Something That Wants to Go Off
M42 and M46 submunitions are palm-sized shaped-charge munitions that US forces used in the 1991 Gulf War, and the VoxelMatters report says clearance of them in Kuwait and Iraq is still going on. The Interesting Engineering report says the new clip is aimed at two of these munitions, the M42 and the M46.
The basic need is simple to state and hard to meet. Before anyone can handle or move an unexploded munition, the parts that could set it off, the firing pin above all, need to stay put. The older procedure held the firing pin still with epoxy or plaster. Both reports describe three problems with that approach. It uses a lot of material, it takes time during clearance operations, and it does not guarantee complete neutralization.
The Submunition Clip swaps that chemical approach for a mechanical one. Instead of encasing the arming parts, it clips onto the munition and keeps those parts from moving. Both reports describe it as securing the explosive components mechanically during disposal work, and Interesting Engineering stresses that it is low-cost.
Who Built It
The clip started as an idea from someone who had done the work himself. VoxelMatters reports that Samuel Larter, an engineering technician at NSWC Corona, proposed it. Larter is a former U.S. Marine Corps EOD technician who served with the 15th Marine Expeditionary Unit. Darren Mansour, of the center's Close Combat Engineering Team, did the design work.
That pairing matters. The best fixtures and jigs usually come from someone who has fought with the old method, teamed with someone who knows how to turn the complaint into a part. Interesting Engineering reports that Larter had the idea of an attachment that could keep critical components from moving, and that Mansour saw how to turn it into a working design.
Why Print It at All?
The reason to choose additive manufacturing here, going by Mansour's own words, is about distribution.
VoxelMatters reports that In VoxelMatters' account, Mansour said he wanted this to be 3D printable "so they didn't have to wait for some supply chain to spin up," with the model saved on an online database of CAD models. That model will sound familiar to anyone who has downloaded a bracket from a repository rather than ordering one. Units that already have printers don't need to wait for a shipment of parts through a supply chain. They need access to a verified file. If a part is lost or used up, they can print another.
The patent filing points to a second route. Both sources say the provisional patent could allow the design to be licensed for outside production. That points to two possible supply paths: units printing their own clips locally, and licensed manufacturers producing them. The reports don't say which will dominate or when either will start. Nothing in the coverage gives a deployment schedule, approved materials, or print settings.
What It Means for Makers
Nobody reading this should be printing anything meant for live ordnance. That work belongs to trained EOD technicians with qualified, controlled parts. Still, the Submunition Clip is a useful case study for anyone who designs functional prints, for three reasons.
First, mechanical constraint beats bulk filling. The older method, as both reports describe it, used a lot of material, took time and could not guarantee neutralization, while the clip is a physical part that holds things in place. Makers face a small-scale version of this whenever they choose between potting a part in resin and designing a fixture that holds it positively. Positive location is often easier to apply and to inspect than a bulk fill, though that is a general design observation, not a claim from the reports.
Second, the design is built around the field, not the factory. The pitch is a file that a unit with a printer can produce on demand, not a part made in one place and shipped out. That is the same reasoning behind spare-parts libraries and printable repair parts in the civilian world. In those settings the hard problems are versioning and verification, not the printing itself: making sure the file someone downloads is the right revision and fits the hardware in front of them. A military CAD database will have to answer those questions with much higher stakes.
Third, the idea came from a user. Larter was not a designer working in the abstract. He had done the job and knew where the old method fell short. Some of the best printed tools start the same way, with someone annoyed by a task they repeat.
Open Questions
The available reports leave a lot unsaid. They don't name a material, give tolerances, or describe what testing the clip went through before the safety award. They also don't explain how the online CAD database will be controlled, or who will be allowed to download files from it. With the primary Navy page unavailable, those details will have to wait for more reporting. What is clear is the direction: a safety-critical part, designed to be printed close to where it is used, has been recognized with a NAVSEA safety award, and a former EOD technician's idea is headed toward licensing.
Bottom Line
The Submunition Clip is a small, cheap printed part that replaces a slow epoxy-or-plaster method that could not guarantee neutralization with a mechanical lock. It is aimed at the M42 and M46 submunitions, has a NAVSEA safety award behind it, and is backed by a provisional patent that could open the door to licensed production. If Mansour gets his way, EOD units will print the clip themselves from a shared CAD library, which is the same idea at the center of maker culture.
