3D printing—particularly in metal—offers a promising way to obtain short-run parts in a hurry. For a business, the benefit is merely filling the order rapidly. But for the Marines, the benefit might be winning the battle by sourcing solutions to fix supply chain problems like a broken component required to return a downed piece of equipment to use.
Manufacturing parts through a 3D printer can cut down on time and cost in comparison to ordering specialized parts, especially if there is no longer a viable supply chain available for a specific part. It also allows engineers to design and construct brand-new designs and are able to test them. This capability provides engineers the creativity to no longer be constrained to the typical methods of manufacturing,
Is hybrid metal AM a part-making resource, a tool-making resource, a resource for repair? It depends on the need, and it depends on the perspective of the particular user thinking about this capability.
Headquarters Marine Corps is now looking at draft policy on additive manufacturing, and the feedback from the MAGTF experience is shaping that policy.
Marines involved in the additive manufacturing effort found all kinds of ways to innovate during the deployment. Within the size confines of the printer, the Marines found all kinds of things to print – wrenches, assembly parts, and protective covers to shield expensive equipment from repeated impact, and even a cover for a laser device that was on back order for seven months and was instead printed in a single day.
“If you have a cable assembly for your utilities, you can only order the entire assembly – but if you don’t need the entire assembly, you just need one little component, you could print that one component for a few dollars rather than have to order the entire assembly which may cost hundreds or even a couple thousand dollars spending on what the item is.
While DoD is interested in additive manufacturing, particularly downrange in operational scenarios where certain items might be harder to acquire, more work needs to be done by industry to certify 3D printed parts and prove that they can stand up to the stresses of military use.
Suppliers are developing “hybrid” applications, where 3D printing and traditional manufacturing techniques like forging are both used to make a qualified part. this technique is attractive for both the commercial and defense aerospace markets that need qualified parts but want to reap the benefits of 3D printing.
DoD is constantly struggling to find suppliers for parts on aging planes that the original manufacturers may no longer produce. In some cases, the companies that built the part have long exited the business, but the DoD requirements remain. Oftentimes we have parts that we can no longer get, and they’re in small numbers, so we can’t get interest in the part of an industry to build something when there’s only a small number and they have to retool or do that.
The only solution at the moment is to pay more. We often can find somebody, but at a really high price, and we’re stuck them because we don’t have any competition. We hope this will change in the near future, thanks to developments in 3D printing.
It’s hardly a new technology at this point, but things have changed for how DoD looks at the potential of 3D printing. The first is that the technology has become more widespread and adopted across the Pentagon.
Where even a few years ago there was resistance to the idea a 3D printed part could be as reliable as a classically forged piece, there is now acceptance that parts printed via additive manufacturing can be secure and stable.
For a globally deployed force, getting something delivered in the right place at the right time can be challenging. DoD is is undertaking a variety of logistics initiatives to help ease that burden and make the force more lethal, and improve visibility of where things are and where they need to be in a decentralised way. That will give it the agility to be proactive, and enable the logistics support to be out in front of where operators need these things.
This logistics command and control will be absolutely essential to link the different capabilities to the people to the different assets to provide the rapid response capability that a combatant commander will need. DoD can’t do this alone, but rather will require support from the industrial base, international partners and the joint force.
In terms of specific initiatives to improve service-wide logistics, additive manufacturing is playing a large role. DoD has been pursing this for some years and still has work to do, advancements in 3D printing allow the force to not worry about the supplying and ordering of parts cutting out the supply chain and reducing timelines for making parts.
The next phase for the service in terms of 3D printing is mainstreaming the process, which means transitioning from plastic parts to metal. Plastic works really well, but we don’t want to replace all aircraft parts with a piece made out of plastic.
“Can we find better ways to maintain these airplanes? Is there some new technology that can help us? Or some new repair processes?”
The 3D printing process is one way to do that.
“We’re responsible for all the maintenance, repair and overhaul of all components that come off the aircraft."
The team has a wide variety of things to maintain, including many parts that would require an expensive bulk buy in the supply chain when they really need only one or two. Examples include mic switch knobs, crew compartment panels, sun visor brackets, and armrests.
The unit already uses 3D printers in various sizes, but they want others with flexible technologies to support making parts that engineers haven’t necessarily thought of yet.
The standby compass cockpit panel dashboard is something the unit is currently prototyping.
Even with larger items, which require more durable parts and aren’t suited to 3D production, 3D prototyping streamlines the process by experimenting with designs that will be manufactured later with metal.
“You’re using the 3D printed technology in order to deliver a prototype that confirms form, fit and function … and then you can be confident of your repair solution or your new part, delivering that to the traditional, organic manufacturing unit that’s going to use multi-axis milling machines to cut metal into that part.
The in-house 3D process is much faster than going back and forth with outside suppliers for parts. “Once you get the geometry, you can print it overnight and have it the next day."
To identify the geometry of the part and print it takes only a couple days. “With diminishing sources of supply, the benefit for us is the flexibility and the agility to respond to a warfighter need.
“The benefit is speed. That’s our bottom line."
Marines have now deployed self-contained hybrid additive manufacturing facility called the “ExMan” unit, or Expeditionary Manufacturing. The ExMan represents potentially the most effective resource yet for enabling deployed personnel to be self-sufficient in providing for their own critical hardware needs, offering a model for how an established manufacturer might proceed with additive, because the Marines are following a learning curve comparable to what a machine shop might expect.
ExMan is already aiding and saving cost for Marines even though it has yet to be deployed and will provide a valuable alternative to existing supply of, for example, unmanned aerial vehicles—drones. These devices are still new, and prone to break frequently. As yet, there is no formal supply chain for needed parts, because there is no understanding yet of what replacement parts are key or how frequently they will be ordered. As a result, some needed parts have a lead time longer than one year. In response, the Marines have been keeping drones flying by making needed parts through 3D printing.
One example of this relates to recognising the use cases. Marine team is developing and evaluating the capabilities of the ExMan. “Having hardware supplies at the point of need is always a problem. For instance, a broken steering-column pinion gear might render a Humvee inoperative, but obtaining this replacement part far forward in the field fast enough to matter might be close to impossible. To respond to problems like this, Marines have long done manufacturing in the field. Existing portable machine shops offer milling or turning capabilities.
Marines are exploring the problem of the pinion gear. Is it now possible to solve a problem such as this one in the field? That is, is it possible to return the Humvee with this problem back to use quickly? The component is too difficult to make through machining alone, but perhaps straightforward to make through hybrid AM. For example, what about 3D printing gear teeth onto a piece of metal tubing? The “innovative mindset” consists simply of this: Recognising that many formerly prohibitive supply chain challenges are no longer prohibitive when additive is added to machining.
Yet a part like a pinion gear is too challenging for systems such as these, for multiple reasons. The part is too complex to make on a lathe or mill in an exigent setting, and carrying enough raw material to be prepared to make a part such as this would represent a problem in itself, since machining a shaft with gear teeth out of solid stock would mean cutting a lot of material away.
Attempting this additive manufacturing at a tactical level was part of an “advancing the force” mission assigned to the MAGTF, to push the Marine Corps closer to its vision laid out in the latest Marine Corps Operating Concept.
As the Marines look to implement the vision outlined in the Marine Corps Operating Concept, the 3D printing initiative to make parts for which the Marine Corps owns the design and can alter it as needed as mission requirements and the threat environment change – are providing a first look at what Marine operations in the next decade may look like.
“The Marines were coming back from deployment saying that we’re seeing quadcopters and things like that going over our positions, so we started to inject that into our training.
“There’s not a lot the regiment can do on its own in order to defeat that threat, so we really worked on mitigating it – practicing good procedures, reducing our signature so we’d be less vulnerable to it.
And then when we deployed we stepped it up a notch – because we were at so many locations across the theater and there are so many different approaches being taken by the joint force, we were exposed to almost all of them, so we tried to bring that together so we can harness that and build that knowledge for our Marines.”
Using the drones in MAGTF operating forward is the perfect setup for innovation and learning that comes from having the full range of Marine Corps assets operating under a single commander.
“It Provides a bias of problem-solving and looking for original solutions, because you have that mix of different capabilities. Also, from an operational standpoint, “some of the best innovation comes when people have practical problems they’re trying to solve. It actually stimulates the creativity to advance the state of the art. That’s kind of what we lived every day.”
Many of the Marines involved already had experience with writing codes, using 3D printers, soldering and other skills needed for the drone assembly, so “just taking advantage of the natural talents we already had out there, we were able to pull them in and use them to our advantage. It helped retention – the Marines were very excited that we were able to do some things faster than we otherwise would have.”
The drone-printing effort contributed to several learning efforts. Hybrid Logistics Working Group had been stood up, with additive manufacturing being a prime focus for the group.
“As we wrestled with additive manufacturing at the tactical level, whenever we came into a supply chain conflict we were able to tap into that group in order to start to address some of those questions.
“What we learned from that is, you need the push-pull, where Marines at the lower tactical level are trying to solve problems today, and you need that immediate feedback to the policy level so that they can remove barriers, because we naturally found them.
“This is new and everybody is exploring it. Through that working group we were able to do it a lot faster.”
A 3D printer works by taking a three-dimensional image or model, and printing the part one layer at a time, upward from the bottom-most layer. The layers are fused together by some sort of adhesive agent. The printer may take hours to finish a part, depending on the level of complexity and size.
This innovative capability enables maintainers to create one-off modifications of aircraft parts at reduced costs in terms of both time and materials to aid in the advancement of Edward’s unique test and evaluation mission.
But the dilemmas are these: Metal AM systems are generally costly, bulky relative to the size of parts they produce and difficult to use given the safety considerations necessary for handling powder metal. These factors are problematic for a machine shop, and prohibitive when it comes to the prospect of letting the Marines use metal 3D printing in the field.
And for the Marines, one more concern is that metal 3D printing ought to operate in conjunction with CNC machining within a single setup, for the sake of truly obtaining the part as fast as possible. That is, the Marines’ interest is in “hybrid” AM combining additive and subtractive operations. For all these reasons, a small CNC milling machine with an add-on metal 3D-printing head comprises the heart of a system Marines are evaluating for making repairs and replacements to hardware items in the field, far from traditional supply chains.
Hybrid system offers an extreme version of the experience a machine shop might have in adding metal AM to its capabilities. The metal 3D printing head mounts onto an existing CNC milling machine in parallel with the metal cutting spindle. The resulting hybrid system can 3D print features and machine those features to tolerance within the same setup.
Heads for metal 3D printing are supplied via various methods of metal deposition, including laser melting of powder spray, arc melting of wire feed, and high-velocity cold spray of metal powder. In the ExMan, the wire-fed metal 3D-printing head mounts parallel to the spindle on a milling machine, producing a system that can build 3D features and then mill and drill them to precise tolerances within a single setup.
The input material is solid wire instead of powder and because current is used to melt the material rather than a laser. It’s not a normal arc-welding process, which generally includes some level of porosity, but instead a lower-heat approach that enables effective deposition of metals at full density.”
This 3D printing by deposition, meaning placing metal along a precise tool path rather than using a powder bed, means a complete 3D part can be built up onto a flat surface. It also means a 3D feature can be built just as easily onto an existing part, with the existing part used as the starting work surface. In short, hybrid manufacturing is a resource for repairing or modifying existing components every bit as much as a resource for making components from scratch.
The search for metal 3D printing capability was blocked at first because powder-bed selective laser melting systems were seen to be unsuitable for deployment and use in the field, given their cost, size and safety requirements.
Now the challenge and the opportunity of metal AM lies in the mindset change necessary to reevaluate challenges such as this. Marines—just like shops adopting AM—need to rethink long-standing assumptions about what kinds of parts can now be fabricated quickly.
Building and fielding the drone allowed Marines the opportunity to develop an understanding of how these things are put together and manufactured locally. And then how can it be used, what are its strengths and weaknesses, what are its limitations so that the Marines better understand what tools can be applied to counter the threats that were being used against them?
To meet objectives, we commissioned this case study to not only optimise current equipment product support Job Site operations and enhance dedication to Field-Level Troops product support services, but also provide the services with the tools, templates and real world strategies so we have capacity to sustain these improvements into the future.
We established the following Job Site scope areas, which framed the objectives of this Case Study:
1. Optimise allocation of Job Site product support resources, including oversight of routine, peak & specialty work orders
2. Design product support programmes for field level unit outreach at Job Sites, including mission-driven reporting & surveys
3. Propose product support approach for receipt of individualised Job Site service level work orders with field-level units
4. Maximise "wrench turning" produce at Job Sites, including product support programmes for continued training, incentives & performance
5. Establish core product support Job Site services, specialised services evaluation & changing conditions.
6. Enhance Job Site performance metrics, including key product support performance indicators, techniques & reporting
7. Provide framework for evaluating the Job Site costs/ benefits of expanded product support services to existing or new troop units
8. Conduct Job Site space requirements assessment, addressing barriers to efficient product support operations
9. Optimise Job Site operations, including product support policies, procedures & performance requirements for on-hand stock parts/tools
10. Evaluate Job Site product support work order rate-setting systems and recommend adjustments to rate setting & replacement