Friday, September 29, 2017

Let's 3D Print Some Stupid

The Marines are learning how to 3D print small quadcopters. (1)

“… Marines built an initial batch of 25 Nibbler UAVs – quadcopters with a dwell time of about 20 to 25 minutes, which can carry cameras or other intelligence payloads and cost about $2,000 apiece to print …”

Wow, you say!  What’s not to like about that?  Unlimited 3D quadcopter printing.  That’s fantastic! 

Uh, back the quadcopter up, for a moment, and let’s look at this a bit closer and make sure it’s as fantastic as we and the Marines seem to think.

Let’s start with capabilities.  A quadcopter with a 20 min endurance is very small, very light, and can carry only a very small payload.  This is not a battlefield roaming, omniscient, eye in the sky, see everything sensor.

“The Marines built, The Nibbler, a four- rotor UAV with a 20-minute flight time capable of looking over hills and around buildings …”

This is a peek-around-the-corner or look-over-the-next-hill type of capability.  That’s nice, I guess, but haven’t soldiers been doing that kind of recon for a thousand years?  Plus, a quadcopter stands a better chance of being spotted and alerting the enemy to our presence than a properly trained soldier who understands stealthy recon.  So, that’s a disadvantage to the quadcopter.  Still, I’m sure there are circumstances where it might be convenient to have a flying, pinhole camera.  That’s right, a pinhole camera – that’s about all a quadcopter this size could carry.  This size craft is not going to be carrying radar, FLIR, or anything else that might actually be useful.

Now, let’s look at logistics.  People tend to think that a 3D printer creates objects out of thin air.  It doesn’t.  It uses a print medium that has to be supplied in bulk.  If you want to print a 10 lb part, you need at least 10 lbs of print medium and that’s only if you have 100% conversion of the medium.  And you don’t.  Printers have a degree of waste.  The conversion is 50% to 90% depending on the printer and part.  So, to make that 10 lb part you actually need 11-15 lbs of print medium. 

Thus, the printer doesn’t actually save any weight or volume in terms of logistics.  If you think you’ll need 100 quadcopters printed, you’ll need to transport 150% more than their weight of print medium with you into the field.  You’ve gained nothing, logistically, and have likely increased your transportation weights and volumes.

How Many People Does It Take To Operate A Quadcopter?

Let’s look at personnel requirements.  A 3D printer is not quite like your home PC printer.  It requires some fairly sophisticated programming and operating techniques.  In other words, you’re going to have to pull riflemen off the line to sit somewhere doing 3D printing. 

“A total of 48 personnel were taught to run the 3D printers …”

We’ve pulled 48 riflemen off the line in order to create a very marginal recon capability.  Is that really the best use of Marines? 

Let’s look at cost. 

“…cost about $2,000 apiece to print …”

You can buy this kind of quadcopter from almost any retail store in America for around $125, ready to fly, with controllers and small cameras.  What are we saving?

Let’s look at time.  It takes a very long time to print an object.  People tend to think a printer can produce a complete, fully functional quadcopter that flies out of the printer and straight to the battlefield.  That’s not even remotely correct.  The printer produces individual components – each component can take minutes to hours to produce - that have to be tediously and laboriously assembled, wired, and tested.  More people, more time.  Why not just have a pre-purchased, complete unit boxed and ready to go?

I have no idea but I would guess that to print all the components for a small quadcopter would require many, many hours.  In contrast, you can open a boxed quadcopter and have it in the air in 15 minutes.  If you have a sudden, urgent need for a quadcopter in the field, printing is not the way to go.  Sure, you could have a supply of them printed up and sitting in a pile, ready to go but then why not have pre-purchased ones in boxes ready to go?  What have you gained?

Let’s look at firepower.  This kind of effort continues the Marine’s trend away from firepower and towards becoming a light infantry with only very limited use.  Quadcopters aren’t going to win a peer war with China, firepower and numbers are.

This smacks of technology for the sake of technology with no real warfighting benefit.  It costs more than buying the same item, it saves nothing logistically, takes far more time, and offers only a marginal capability, if that.  Personally, I’d rather have a scout-sniper do my recon.

The military is so caught up in the technology craze that no one bothers to ask how any of this will result in greater lethality on the battlefield.  Instead, the military seems like it’s desperately searching for some use for 3D printing just to be able to say they can do it. 


(1)USNI News website, “Marines’ 3D-Printed ‘Nibbler’ Drone Creating Lessons Learned on Logistics, Counter-UAS”, Megan Eckstein, 27-Sep-2017,


  1. $2,000 is way too much, Marines should just buy Chinese :)

    The ~ $500 Xiaomi Mi Drone quadcopter possessing a three-axis gimbal and a camera and can record at 4K at 30FPS with bundled remote control allows you to transform your smartphone into a viewfinder for seamless navigation through the camera.

    The drone houses a 5,100mAh cell and can remain airborne for a total of 27 minutes, along with an accessory to jam in more battery packs simultaneously for added flight time with support for GPS and GLONASS.

    Xiaomi MI Drone Official Video #SamiLuo

  2. RE: "Plus, a quadcopter stands a better chance of being spotted and alerting the enemy to our presence than a properly trained soldier who understands stealthy recon."

    This is amazingly incorrect. No matter how well trained in "stealthy recon" a person is, they can't see through a door, nor through the walls of an office building that needs clearing. In the early parts of the Iraq invasion they literally ran out of grenades trying to clear command/HQ office buildings the traditional way.

    A small disposable man-pack UAV lets you enter each space and view it without risking a rifleman or consuming a grenade or other ordnance first. Having the ability to quickly deploy a "cheap" set of eyes that looks around the next corner, or can be thrown through a cracked doorway saves a lot of wounded or dead privates. Per unit that lack of attrition in personnel means each unit stays in the fight longer before needing rotation and replacement (even for just a few hours). Maintaining combat power in an urban fight can be exasperatingly difficult due to the easy concealment it affords both sides - with exposure usually coinciding with the first shots. Recon by dead private is an expensive and time consuming process. Any bit of tech that can see or trigger enemy responses is desirable. It has to be cheap, small, and easily replaced because in an urban fight you will lose a lot of them.

    That is why you want the ability to generate them on demand as near the point of conflict as possible. A MEU going ashore could quickly see its drone attrition skyrocket compared to training rates - do you want to suddenly hit the civilian supplier with a request for 10,000 units delivered yesterday, or start cranking them out aboard the amphib on a printer? Ideally you do both, but having the capability to replace losses on site without concern for commercial inventories (nor the logistics of getting them from the civilian supplier to the warfighters on the ground) makes a lot of sense. Even at a wastage rate of ~50%, storing the raw printing materials is more desirable than the finished product because raw materials *typically* take less cube, which is critically important for amphibious operations.

    A last note regarding lethality. Once you have the processes in place to generate and operate small UAVs for infantry use, adding lethality to the drone itself is simple. Right now at the platoon level we are working with UAVs as the WWI military was working with manned aircraft. They began as observation and scouting platforms to get the ball rolling. Once they are in routine use, the next step is weaponizing them. The bad guys are already using modified quadcopters with 40mm grenades attached - a field expedient light bomber. We will do the same. Instead of fragging each office/room in a clearing operation, add one to the drone that is already scouting the room and only use it when necessary. Replace with flash/bangs when civvies may be present. This is not tech for tech's sake, just incremental improvements to the ways and means of utilizing new tech for expeditionary forces.

    1. "This is amazingly incorrect. No matter how well trained in "stealthy recon" a person is, they can't see through a door, nor through the walls of an office building that needs clearing."

      This is amazingly incorrect. No UAV can see through a door or walls. No UAV can open a door. On the other hand, a person has a variety of methods for "seeing" through a door ranging from IR to audio to cameras under the door to simply looking through windows.

      You also seem to think I'm arguing against unmanned sensors. Where did you get that impression? Certainly not from this post. I'm all in favor of unmanned sensors, of whatever type. If you read the post, you'll see that I'm against 3D printing of UAVs - not UAVs themselves.

      If you think you might need 10,000 UAVs then procure them before the operation. Entering an operation without the requisite equipment is just poor planning and if you think you can suddenly crank out 10,000 units then you're living in a fantasy world.

      Thanks for the note on lethality and UAVs. I had no idea a UAV could be lethal. That's incredible! I read military articles all day but I've never heard of such a concept. Thanks for making me aware of it.

      I don't think you read the post at all. If you did, you certainly did not comprehend it!

    2. The potential with the 3d printing is that 20 lbs of material can be used to make quadcopters sure, but if you don't need them you can print spare mags, some weapon parts, fuel cans, tent poles, etc. The price for the quadcpoters probably mainly comes from the parts you can't print, like batteries, control & radio circuits, cameras, etc. The main thing is if your unit needs something now, you don't have to hope they haven't run out and you have to wait for it to be shipped from the US. Also remember this technology is still in its infancy, we're still exploring what it can and can't do, what it is better than other alternatives, and where its worse.

    3. I don't think you appreciate how long it takes to print something! Sure, if you only need one fuel can and can wait several hours for it, and were too stupid to bring enough with you, and want to pull several riflemen off the line to make it then, yes, it's a great idea.

    4. "The price for the quadcpoters probably mainly comes from the parts you can't print, like batteries, control & radio circuits, cameras, etc."

      Price aside, don't you see the gross inefficiency of having to not only bring along a printer and print medium but also separate boxes of batteries, circuit boards, wire, cameras, etc., and then pull combat soldiers off the line to unpack each of these components, print the parts you didn't bring, hand wire and assemble them, test them, and transport them to wherever they're needed - as opposed to just bringing actual UAVs with you in whatever quantity you think you'll need plus some extras?

    5. ComNavOps, while I generally agree with your premise of pulling away combat personnel for jobs that should remain with supply personnel (which these may have been), I think you cloud your argument by attacking 3D printing and its potential based on the simpleness/silliness of this exercise.

      Although printing toy UAVs in the field is almost useless as you say, the ability to print locally (ships in Navy/Marine case) will most likely become standard procedure for many things in 10-20 years. Although limited to slowly printing plastics and basic metal forms now, research is already progressing on complex shapes and materials.
      Processes have already been developed for food, strong metal alloys, as well as bone and tissue (although barely beyond theoretical, in very precise lab experiments).

      You also miss the logistics potential. Even with a 50% material waste (reality is much lower), this can be offset through less storage volume for bulk materials versus the equivalent fully produced parts and packing materials.

      Speed is currently the biggest hurdle today, but industrial printers are progressing well beyond the home/hobby models you describe. You may be able to get a fully assembled toy UAV in a day or two, but good luck getting an overnight replacement fan blade for your shiny new F-35 (and yes, several engine manufacturers are already working towards this goal).

      So yes, your premise about the usefulness of this particular exercise is silly, but the potential of this capability to the military clearly is not.

    6. "silliness of this exercise"

      Well, we agree on that!

      "Although limited to slowly printing plastics and basic metal forms now"

      If and when the technology advances, I'll reevaluate.

      "Even with a 50% material waste (reality is much lower), this can be offset through less storage volume for bulk materials versus the equivalent fully produced parts and packing materials. "

      No. The individual packing materials and storage volume for the circuit boards, wire, connectors, screws, radios, and other parts that can't be printed have got to far outweigh a single, packaged, complete UAV unit with all the individual components "packaged" into one unit. Go buy all the individual components you'd need plus the printer and medium and then tell me how that volume, weight, and packing material compares to a complete unit in one compact box. There's no comparison.

      "good luck getting an overnight replacement fan blade for your shiny new F-35"

      Either you have a new blade on hand because it's one of the standard spare parts based on maintenance history or you haven't got one because no one has ever seen one break before. If the later is the case, why would you have a 3D print program all ready to go when no one anticipated needing it? Be consistent in your logic. If you can anticipate to the point of having a prepared program for the printer then you can anticipate and have a spare on hand.

      Finally, we are years or decades away from being able to print parts that require exotic materials. To be fair, you allude to this when you acknowledge that we can currently only print plastics - I'm not sure that we can even print any useful metals like stainless steel, titanium, inconel, etc.

      Again, if and when the technology changes, I'll reevaluate. Until then, let's leave the riflemen in their foxholes and let's spend our development dollars on better armor and explosives. Firepower wins wars, not 3D printing.

    7. Another aspect to 3D printing is material of construction. A 3D printer is, right now, limited to a few types of cheap plastic. That's not going to produce much in the way of milspec products! There's been some experimentation with some metal parts but I don't know how far that's come.

      The larger point is that if you expect a 3D printer to produce any imaginable part then you'd need to have bulk supplies of all kinds of materials (plastic, composites, ceramics, metals, alloys, etc.) even if the printer could work with the materials. More likely, you'd need multiple types of printers for each type of material. Multiple bulk raw materials and multiple types of printers all for the convenience of not having to bring a spare part along with you? The logistics efficiency just flew out the window!

      Further, 3D printed parts are very crude in their finishes. For some things, that's fine but for most precision parts (like a fan blade) that's totally unacceptable and non-functional. Someone would have to do surface finishing of the part. That requires machine shops. Are you really sure it isn't easier and more efficient to just bring some spare parts along?

      The more I think about the fan blade comment, the more I chuckle!

      You seem to have a vision of every soldier crouched in his foxhole beside a personal 3D printer. He sees an enemy, instantly prints a grenade, defeats the enemy, and celebrates by printing up a bottle of champagne!

      I see armies marching triumphantly into battle with nothing but a 3D printer for each soldier - they can print their rifles and tents after they get to the battle!

      I see future war movies about a heroic soldier fighting his way through to bring 3D printer medium to his pinned down buddies. Or, maybe, a movie about heroic pilots braving enemy fire to airdrop 3D printers to besieged troops. At the end of the movies, the heroes will receive medals at a ceremony with the medals printed right their as the presentation occurs! All right, that's enough. I'm just having a little fun with this.

  3. ComNavOps completely missed the point of the Marines exercise. AM is very important when the Marines invade
    Mars, lots of local materials, very long delivery times of parts via LSTm from Earth.

  4. There's another much more important thing - BIG military industrial complex won't never allow such "improvisations" in the military service itself.

    What i mean is, if 3D printing some military useful systems can be done by the military itself in the not so distant future .. then some companies will loose they're profits, they're never allow it to happen.

  5. College engineering departments are big on 3-D printing. I think it has some manufacturing potential, but it's not the future of all manufacturing that it's being promoted as. Ships have traditionally had limited manufacturing abilities on board in the form of machine shops. 3-D printers may prove useful too. Never saw marines toting lathes and mills out into the field. As stated above, taking manufacturing equipment and materials to the field and building drones is silly. For the given bulk and weight, they could take multiple assembled drones.

    For the tent stake: find a stick, sharpen it with your bayonet, and pound it in with your entrenching tool.


    1. "Ships have traditionally had limited manufacturing abilities on board in the form of machine shops."

      Yes, they have. Ships were once upon a time expected to perform their own repairs and a functional machine shop was a critical part of that. Today, we're moving away from on-board repairs and my understanding is that ships are being built with no or very limited machining capabilities. The LCS is the extreme example of no machining capability that I'm aware of. I don't know what the Zumwalt has, if anything.

      "For the tent stake: find a stick, sharpen it with your bayonet, and pound it in with your entrenching tool."

      Now that's some common sense, useful technology!

  6. DARPA looking to line their coffers again? I just can't imagine this is more cost-efficient or timely in turn-around than an off-the-shelf UAV, at least not at the 2000 dollar price tag. 3d printing is certainly evolving, but I think this is just an exercise in justifying DARPA's need to do expensive research through excruciatingly slow university collaborations.

    The "fan blade" comment posted earlier is comical. A 3d printed ceramic or polymer composite that meets milspec for a fan blade replacement in an F35? You could singlehandedly kill GE, Rolls and Pratt with such knowledge. Please patent that now.

    1. "The "fan blade" comment posted earlier is comical. A 3d printed ceramic or polymer composite that meets milspec for a fan blade replacement in an F35? You could singlehandedly kill GE, Rolls and Pratt with such knowledge. Please patent that now."

      That's a great answer to the 3D fan printing comment. When you get to high tech systems, the individual components are usually exotic materials and finishes with exacting specifications and characteristics. To think we'll simply print one up with a 3D printer is fantasy.

    2. While producing AM parts in the field will not be practical for a long time, use of metal AM is growing because it is relatively easy to print exotic allows that are difficult to machine via traditional methods, such as many titanium alloys and high-nickel steel alloys. They material just needs to be weldable. Surface finishes are about the same as investment cast parts, and electropolishing and superfinishing can be used to bring parts within tolerances. Hot isostatic pressing AM parts ensures that they are fully dense and full strength prior to heat treatment. It is by no means a cheap process, but AM can facilitate drastic reductions in the number of parts and the use of designs and materials that are not possible via purely reductive machining. GE is investing heavily in this technology, particularly for aero engines.

    3. The kind of AM process you're describing is like comparing a modern jet fighter to a WWI biplane. Beyond the underlying generalized concept, there's little in common. We're talking about today's (and tomorrow's!) run of the mill 3D printers. You're talking about very advanced processes completely unsuited for any combat field application.

  7. What do you think about zeppelins? It looks like zeppelins carrying hundreds of tons with much less fuel consumption than a jet is possible with modern technology. Can they have any utility at a war?

    1. You tell me. What use do you think a giant, slow moving, non-stealty object would have in combat?

    2. I didn't know. That was why I asked to you. I think I got my answer.

    3. Okay, that's fine. I think you've surmised my answer. There is very little use for a giant, slow moving, non-stealthy object in combat. It might be useful as a rear area transport but the slow speed and inability to operate at speed in storms or headwinds probably negates even that.

      Another possible use is as an elevated sensor platform. A ship could release and hover a blimp with a radar high overhead and extend the radar horizon. However, being so easily detected (plus radiating a radar signal), it would give away the location of the host ship. It could be sent many miles away but it would be non-survivable.

      The last idea is as a rear area communications relay but I'm not sure there's really any need for a rear area comm relay - in the forward battlefield, yes, but in the rear, probably not.

      Sorry, but I just can't think of any viable combat use.

  8. 3-D printers are not going to kill the MIC. In addition to making the individual parts, there are other processes such as surface finishing, special coatings, and detailed assembly instructions. Just because you can 3-D print something that looks like a jet engine turbine blade, you are a long ways from having a working jet turbine.


  9. Being new to 3D printing/additive machining, one usually starts by making simpler parts first to gain experience to make more complex parts. Making parts for a drone is just a starting point. And, I wouldn't make too much out of the conversion rate as the excess material can be recycled and reused.

    AM has some advantages over traditional machining methods, like making many parts at once or makings parts whole by eliminating welds and complex machining setups. Of course, it depends on the complexity of the part and the economics involved. In general, hogged out parts made from plate or bar stock are good candidates for AM.

    I can imagine some practical military uses of AM in the field, such as making parts to repair a vehicle, a generator, or an artillery piece. Conversely, one could make parts to enhance the armour protection of a vehicle or an entire FOB. You could also make parts for a weapon or even an entire weapon. The Army recently 3D-printed a grenade launcher, including the ammo.

    Let's see how this one plays out.

    1. My problem is as much with the underlying concept as the exact parts that can be made. The idea of pulling combat soldiers off the line to make parts that can just as easily (more easily, in fact) be brought with supplies is just silly. For that one part that no one thought would break but did and, therefore, no one thought to bring a spare, that's just not worth the transport of a printer, power supply, medium, and pulling soldiers off the line. In that rare case, in combat, there's probably dozens of the same "thing" that have been disabled and the missing part can be pulled off any of them. Combat has a way of supplying loads of unintended spare parts!

      This just strikes me as technology for its own sake or a solution looking for a problem where none exists.

      A high end additive manufacturing machines that might actually be useful are not suitable for combat field conditions. Most such machines require exquisite care, scrupulous cleanliness, skilled technicians, and advanced programmers - not the conditions normally found in the field in combat.

      Sometimes it's not necessary to wait to see how something will play out. Sometimes it's obvious how it will play out. Now, 20-50 years from now when 3D printing has advanced to Star Trek-like matter replicators, then we can re-evaluate.

    2. That some scientists want to play around with this is fine - stupid but fine. However, when it takes 48 Marines away from precious combat training and wastes their time learning 3D printing, then I have a problem with it.

    3. "This just strikes me as technology for its own sake or a solution looking for a problem where none exists."

      Thank you! I'm not against new technology when it will help the soldier, sailor, airman, or marine do his job. But this 'got to have it because it's new tech' is out of control.


    4. "The Army recently 3D-printed a grenade launcher ..."

      And took days to do it! From a Popular Mechanics article about the event,

      "The grenade launcher barrel and receiver took about 70 hours to print and then required 5 hours of post-print finishing."

      Over three days to manufacture one item! And, that was not simple 3D printing. It used very sophisticated instruments that would not be remotely suitable for field combat use. Plus, it still needed non-printable parts.

      It was a PR stunt.


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