4
$\begingroup$

Set in the near future each soldier is equipped with a sophisticated handheld 3D printer and a couple of cartridges, then sent straight into the battlefield. Depending on the terrain and what kinds of enemy they are facing, these soldiers can adjust and adapt on the spot (assuming the printer can produce an assault rifle or working grenade within minutes). The enemy are still using conventional weapons.

Will the traditional way of manufacturing weapons becomes obsolete?

$\endgroup$
  • $\begingroup$ Not if the printer can't produce something more sophisticated than guns and grenades. In the described scenario everybody has the same weapons, but the enemy has them for immediate use whereas you have to print it first. And if your printer breaks you have no weapons at all - if the enemies rifle breaks he can still hurl grenades at you. $\endgroup$ – Eike Pierstorff Aug 7 '15 at 10:31
  • 1
    $\begingroup$ Printing explosives like grenades and bullets would be a far future scenario (if that) not near future. $\endgroup$ – Avon Aug 7 '15 at 10:53
  • 1
    $\begingroup$ I see a few problems here, but the main part is that from my experience (which is few), a few minutes in a combat situation can be a really really long time. $\endgroup$ – Magic-Mouse Aug 7 '15 at 12:58
  • $\begingroup$ Your best option in many scenarios might be to just hit them on the head with the printer (which is not quite ideal IMO). The first time the enemy identifies printing as your primary method, they will absolutely not wait a second to take you out when spotted. Where they'd normally try to get better intel or arrange covering fire, their new goal will be "annihilate them while they have no/few weapons." Remember that printing a gun isn't enough, you need bullets to go with that thing, printed one at a time. $\endgroup$ – Geobits Aug 7 '15 at 15:44
  • 3
    $\begingroup$ 3D printing does not do transmutation of elements, or even chemistry. If you want to print something, you need a stock of the material(s) that it's made from. $\endgroup$ – jamesqf Aug 7 '15 at 18:17
7
$\begingroup$

The issue here is what materials you can use with your personal printer. 3D printing is nice because you can make many things that you couldn't otherwise. If you look a this article by Nick Allen, of the 3d Printing Company 3d Print UK, you'll see that he, an expert, does not think 3D printing can replace all manufacturing processes.

Here is why 3D printing weapons is difficult. These issues could, at some future time, be overcome. Until then, your soldiers need to contend with these facts in addition to their enemy:

  • Laminate weakness: 3D printed materials are weak in one direction, so things like a gun, which can be safely and repeatably used, are really hard to make. This is due to the fact that the weapon parts are made 1 layer at a time, so molecules are not as strongly bonded together between layers as they are to others within the same layer. This gun, which can fire 50 shots before failure, was impressive enough to get press attention. That was made using very-high end 3D printing equipment, not the kind of stuff you find in a hobbyist's home. 50 shots is not enough for military applications, nor is such a printer portable. (This is science fiction, though!)
  • Material Weakness: You need to choose what material to make your guns out of. Plastic is cheap, and easy to work with, but doesn't give you the strength you need to fire a military grade round. Metal makes more sense, but you need to cool it off wicked fast to make it and use it within minutes. Such rapid cooling will result in warping, which can further introduce weaknesses. A gun which explodes in your hand is worthless. (Grenades, though, are meant to fail.)
  • Speed: 3D printing is fast for a manufacturing process. Printing a gun could take days or weeks, depending on the parts. Of course, your hypothetical printers are even faster, so this isn't an issue, but cooling it off quickly enough for human use will warp it, or introduce more weaknesses. This also means that using a gun or other object meant to be used more than 1 time use may need to wait for everything to cool. In a battle, where seconds matter, this can be too long. You may be better off simply melting metal and flinging that at your enemy!
  • Finishing Processes: your product from your printer may need additional processes to smooth it all out and make the parts on your gun fit together. After all, small imperfections in a barrel can greatly affect a gun's accuracy and longevity. More modern and complicated 3d printers can be very precise, but your model fitting together is not guaranteed.

In summary:

Do not 3d print (rapid prototype) a weapon you want to be reliable or to see repeated use. One-time use things, like grenades, bullets, and other expendable weapons or ammunition are good candidates for 3D printing. (Bullets may be a poor choice simply because casting them can be so much easier...)

The laminate weakness introduced by the rapid prototyping (3D printing) process itself is a serious issue, which means all other manufacturing operations will not be outdated or replaced by rapid prototyping. Some processes may be replaced for some items, like casting, but processes like forging may never be replaced by a 3D printer. This is especially true when the item in question needs to be durable or strong, such as the firing pin or barrel of a gun.

|improve this answer|||||
$\endgroup$
  • $\begingroup$ Semi-related, look up the process called "sintering." It's the preferable way of 3D printing metal objects, using a fine metal dust and flash-heating it with lasers, but has its own complex issues and downsides (such as needing a vast quantity of unusable base material). $\endgroup$ – Draco18s no longer trusts SE Apr 12 '16 at 16:20
4
$\begingroup$

The primary advantage of a 3D printer is the ability to make complex shapes and forms more quickly and easily than conventional forms of production (casting, milling, forging etc.). Firearms and hand grenades are designed and manufactured in such a fashion that 3D printing does not provide any appreciable advantage over steel stampings,pressing and spot welding, and as noted, a barrel requires high strength material to operate reliably for a prolonged period.

The second issue is that for many items, 3D printing still requires assembly. If your device has parts made of metal, plastic and ceramics, each individual piece must be printed and then assembled (This is making the big assumption that the printer can deal with each type of material. More likely you need separate printers for each material). Even if all the parts are of the same material, a working device is not monolithic, so individual parts like the barrel, bolt, receiver etc. still need to be made separately and then assembled.

Finally, ignoring the issue of providing energy to the printer in the field, you need raw materials in order to print. While you might need less raw materials because there is less waste from machining etc., if your rifle weighs 3 kg unloaded, you need at least 3 kg of raw materials. A solider wandering around in the field with a printer, multiple bags of powdered raw materials an a portable hard drive with the templates of every conceivable device he might need to print will be more burdened than a soldier armed and equipped in a conventional manner, and most of what the 3D soldier is carrying won't be immediately useful anyway, until it gets printed.

Printers do have a place in a logistics chain, especially where you need access to lots of complex parts and have limited storage space. The maintenance hanger on an aircraft carrier is a good example. Being isolated and at the end of a long supply chain is another example, the ISS is an extreme example, and future "space navies" will have their ships outfitted with fully evolved examples of 3D printers. 3D printers have a place in the military, but not on the front lines.

|improve this answer|||||
$\endgroup$
1
$\begingroup$

3D printers could be very useful for soldiers in the field, however, printing weapons is not one of them. As a soldier you need a weapon, might as well give it to them right off. On top of that, things like grenades need gunpowder or some other explosive. That means you'd have to have the explosive as a separate 'cartridge' and once again it's easier to have them pre-assembled.

The printers especially for a field unit are going to be able to print one kind of material, likely being able to vary in stiffness/hardness. This could be used to replace broken pieces of equipment, say a buckle, a firing pin, eating utensils etc. The printer would need to come equipped with many standard items in it's library, and the ability to make ad hoc items.

Soldiers tinker and when bored come up with interesting ideas. The printers could really be a lifesaver.

|improve this answer|||||
$\endgroup$
0
$\begingroup$

The soldier in the field would not care about a 3D printer.

The support staff however, mechanics and maintenance in particular would be thrilled to have a 3D printer, if it can print parts in metal.

...which 3D printers can.

3D printed turbine engine

|improve this answer|||||
$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.