# Do 3D printers in space stations mean a significant cost reduction?

I just watched a VSauce2 video, at the end of which certain NASA animations were shown about some of their recent innovations. One of them included use of printers in the ISS.

Do they actually mean a noticeable decrease in cost? I mean, I'm aware that bringing equipment up to these places has huge costs, and I assume 3D printers may decrease the amount of said equipment, as they can create it up there.

What are they precisely used for up there?

• Someone else may be able to find this as I am unable, but I fairly recently read a story about either NASA or the US Military creating 3D printed clips to replace some really expensive ones that they had to buy from a specific company, potentially saving them thousands if not millions. – SGR Jul 28 '16 at 10:05
• Theoretically, yes. If you had feed-stock enough for one tool but plans for a hundred tools that you might need, then that would save you bringing up all one hundred tools just in case you needed them. – Richard Jul 28 '16 at 10:39
• I can't say what they're being used for for certain, but I can point to some logic. If you are certain that you're going to need a replacement item, 3dprinting in space isn't effective. However, if you are not certain whether you are going to need the item, you can defer the decision whether to launch item into space or not until later. Any wrench or tool that doesn't need to be made remains in a reusable material form for use on future items. The open question would be whether enough of these choices can be deferred to pay for the cost of the waste and the printer. – Cort Ammon - Reinstate Monica Jul 28 '16 at 19:55
• I can't get the image of a distinguished physicist sitting at a conference table and putting 3D-printed components in a glass of ice water out of my head. – Tobia Tesan Jul 29 '16 at 13:08

A 3D printer on station isn't likely to lead to direct cost savings; the range of items it can replace are limited, and it has to be supplied with feedstock mass in any case; it won't allow for significantly fewer supply launches.

The primary benefit is that it can allow for the repair of a system the astronauts would otherwise have to do without until the next scheduled supply - whether a nonessential but convenient item, or a scientific experiment, or, conceivably, even a mission-critical or safety-critical part. This would have a definite impact in terms of return-on-investment, but that's not the same as cost savings.

• Just keeping an astronaut or an experiment on station has a cost, so a time saving for a part for an experiment which otherwise would have to be postponed or repeated after the next supply becomes a cost saving. – Pete Kirkham Jul 28 '16 at 11:45
• That's what I mean by ROI. It's not likely to make a difference in the total number and timing of launches, but it can make a difference to what gets accomplished while they're up there. – Russell Borogove Jul 28 '16 at 13:19
• I added a new answer, but it could result in some significant supply savings. The ERASMUS project I mentioned is the most immediate example that could do this. It is a bit silly that the savings are in the form of wet wipes, but alas, such silly things often seem obvious in hindsight. I'll be interested to see how it goes. – fuchstraumer Jul 29 '16 at 17:55

The 3-D printer on the ISS is more for testing purposes than anything. The idea is that for really long duration missions, a 3-D printer will allow them to make something in case something breaks, or they realize they need something that didn't come initially with the ship. So far I can only find a few things that have been made, including a ratchet, several test items, and a wrench. It seems the later was actually used as needed, the rest are just test artifacts. There is a lot of promise, a 3-d printer can potentially save a significant amount of launch weight, not to mention reducing the spares required on a ship, but overall, they are still trying to figure out exactly how to best use them.

As has been mentioned, the real benefit will be for those things that break, aren't life critical, but are needed sooner than a few months that can be taken to get the part from the ground. To my knowledge the 3-D printer has been used once for such, to print a tool.

• Yes, it's going to take some testing in microgravity before anyone would rely on them (e.g. cooling rates depend on convection, dimensional accuracy depends on cooling, usefulness depends on accuracy). Just like any other new technology going into space. – Chris H Jul 28 '16 at 11:03
• "save on launch weight", well that's assuming it's built from in-situ resources... – mb21 Jul 28 '16 at 16:36
• No, actually. It's easier to pack in bulk than it is to pack something delicate, you need less protection for a block of wood than a figurine, for instant. – PearsonArtPhoto Jul 28 '16 at 16:38
• @mb21The eventual possibility of saving on launch weight comes—as I see it—from the ability to launch and store feedstock massing less than a full set of spares for the systems you will maintain using the printers. That calls for a flexible and reliable printer, and only covers parts you can afford to wait through some print cycles for. You need to support many systems to be confident that the mass of feedstock needed (plus contingency) really will be less mass than the bringing a warehouse. All and all it's a quite a ways in the future, but you have to start somewhere. – dmckee Jul 28 '16 at 16:56
• And as for cost-saving, there is one potential, huge though unlikely to occur cost saving: preventing necessity for an emergency launch to provide mission-critical replacements that can't be delayed until next scheduled launch. – SF. Jul 29 '16 at 5:07

I disagree vastly with the majority of the answers here - there are a large number of recent NASA SBIR/other grants that show the agency firmly believes otherwise!

Currently, the 3D printer on the space station is naught but a research one and is a poor one at that. The company that made it is run by a... not so nice fellow that didn't do a good job of building it. It has served limited use due to this.

The primary cost savings could arrive through recycling of the materials onboard. This would allow for reusable utensils, reusable tools (tool broke? if you still have material, it can be reprocessed), purpose-made parts for performing experiments (recycling makes this not at all wasteful), and so on. Utensils especially are useful - if they can be recycled, they will be sanitized when the material is melted at its usual temps! Currently, astronauts must wash all of their utensils with wet wipes since running water isn't the best idea on the ISS. This generates a (hilariously silly) amount of waste in the form of nothing but wet wipes. Which also must be sent up as supplies. And the astronauts say that the utensils can get fairly gnarly after a while... so being able to print single-use recyclable utensils lowers waste generation, lowers supply requirements, and increases quality-of-life (in some small measure) for the crew. All large cost savings!

The issue isn't with the technical readiness of 3D printers for space station employment. Even the most basic of printers is capable of printing in zero-g in its stock form. The issue that requires some engineering is bed adhesion, and removal of the byproducts generated by melting ABS/PLA/Ultem-1010. These fumes can be hazardous and must be removed from the build volume with air cycling (or must be contained while the machine is running, then purged).

ERASMUS is the utensil recycling idea I mentioned - can see that it was funded here: http://www.parabolicarc.com/2016/05/06/nasa-selects-tethers-unlimited-sbir-awards/

Note that the same company/division is currently building this as well - probably not a coincidence, once you figure one of these out the rest are natural evolutions of the starter concept. Neat stuff! -

http://www.geekwire.com/2016/nasa-firmamentum-3-d-printer-recycler-space/

A 3d printer does not give direct cost savings, it's cheaper to launch a pre-made object than the feedstock it takes to print it (there's always some material waste when 3d printing), plus the weight of the printer itself.

What a 3d printer gives is the ability to prototype. 3d printed plastics are weak compared to cast plastics and nowhere near the strength of metal, you couldn't use them for anything load bearing. You can, however print a part, see if it works, and then tweak the design. Once the design is right the design can be given to someone on the ground to manufacture and send up on a later re-supply. For non-load bearing pieces you could use the 3d printed materials directly, meaning you aren't paying for something to be manufactured. It also gives the astronauts the option to design and implement their own made solutions, meaning less ground support. These may well translate into cost savings but it's impossible to quantify how much.

• But you can print tool steel as well. Conventional methods are still more acurate, though. – Crowley Jul 28 '16 at 13:44
• You can print steel but I don't think that would work out well in space. A 3d chocolate printer would be pretty good for morale though! – GdD Jul 28 '16 at 14:29
• @GdD You can print steel selfie stick at least. – MolbOrg Jul 29 '16 at 3:32
• 3d printed plastics are weak... Not convinced of that, except of course as far as perhaps how strong various structural members might need to be or various steel tools, etc. I received a small 3D printed artifact as a gift some 8 years ago, and it's plenty hard enough for many purposes. Printed w/tech that was a bit older at the time, and I suspect the tech has significantly improved. But it'd also depend on how the specific printer worked and the material. – user2338816 Jul 29 '16 at 8:38
• I should probably qualify that statement a bit better @user2338816. 3d printed plastics are not as strong as cast plastics, this is due to the nature of the way the 3d printing process works - successive layers melted on. – GdD Jul 29 '16 at 8:50

Yes and no.

Let's pretend that the 3D printer can print anything if it has equal mass feedstock. Let's also pretend there is a static 10% waste in feedstock for the printer.

Now, with those rules. It is more expensive to use the 3D printer in many situations. The 10% waste would totally ruin it. However there are two areas that would really make it worth while.

1. It would be cheaper to carry 100 lbs of Feed stock and the plans for 1,000 1 lbs tools then to carry 1,000 1 lbs tools. Replace tools with anything.

2. It would be cheaper to carry 100 lbs of feed stock and print a 990 foot sheet, then it would be to try to fly a 990 foot sheet into space.

Now with those two examples you can begin to extrapolate examples where it may be better to print than to carry.

The real problem is that a 3D printer can't just print anything. It's very limited. Limited by size, shape, material, and function (moving parts). For example you can't print a motherboard with it. Even things like a tennis ball are not gonna happen.

So why take it into space? Well the biggest reasons I can see are to test its usefulness. There is potential there. And to use it to replace or repair some equipment. Basically, if you just need a washer, print the washer. Don't launch another pod, or evac the station because you need a tiny washer.