23 thoughts on “3-D Printing And Spaceflight”

  1. Excellent overview (and great points on mass differences) , though personally, I think they missed one example that is very applicable to spaceflight; using a 3-d printer to print a regenerating rocket engine out of the advanced alloy Inconnel. It’s a better way to produce a rocket engine (no seams to weld, less mass, less costly, etc.) I’d have thought that was years away from being plausible, but I was wrong, it’s being done now (actually, it started last year). It’s how SpaceX is making super dracos.

  2. The best use of 3D printing is still rapid prototyping. And with modern techniques it’s possible to use 3D printing to manufacture full-strength parts (e.g. by 3D printing sand molds or by 3D printing wax parts for investment casting, and so on) with a lead-time of only a few hours, instead of days or weeks. It also makes it possible to reduce the size of the “industrial foundation” necessary to produce parts in limited quantities, which has significant applicability for off-Earth industry of course.

    One big leap in technology that I think a lot of people haven’t clued into yet is in situ R&D of spacecraft. If you have a small-ish space station in orbit with a handful of crew and you can run it at fairly low cost and get shipments from Earth fairly cheaply then it starts to make sense to develop spacecraft in space. Just as with Earth-based prototyping you’ll largely be tearing down and building up with the same components but with some slight changes here and there. With a minimal footprint manufacturing capacity (a few machine tools plus 3D printers and so forth) it’ll be possible to have a rapid turnaround on new parts translating to new designs which can be tested almost immediately. Even if the production line versions of the vehicles are ultimately built on Earth the ability to iterate on designs and testing so rapidly in orbit will accelerate development a great deal.

    Also, that sort of capability naturally dovetails with in situ refurbishment, repair, and recycling activities, all of which are likely to be highly lucrative.

  3. Only if we man up and not because of additive manufacturing.

    Elon has both a can do attitude and a realistic business sense. Others with less resources do as well, but all of them are in the minority.

    3D printing is great but it’s not an enabling technology because we are able without it. They should certainly include it but the real problems are attitude, not technology. The definition of economics makes it plain… using limited resources that have many uses. Thinking only the latest and greatest is part of the problem.

    1. astronauts on the ISS are able to manufacture small parts as needed today? 3D printing doesn’t enable them to do what is currently not able to be done?

      “An enabling technology is an invention or innovation, that can be applied to drive radical change in the capabilities of a user or culture. Enabling technologies are characterized by rapid development of subsequent derivative technologies, often in diverse fields.

      Equipment and/or methodology that, alone or in combination with associated technologies, provides the means to increase performance and capabilities of the user, product or process”
      http://en.wikipedia.org/wiki/Enabling_technology

      Increasing the capabilities of the user is exactly what 3D priniting allows.

      1. People are enamored with 3D printing precisely because it allows people with no skills to make some of the things people with skills have been making forever. Yes, there are a few things that are simpler when done additively.

        I plan to get a printer myself but I’m not going to get caught up in the hype.

        Not quite as bad as the Segway but very similar.

        This is one of the problems with leaving the farm. Farmers are few in our modern society but they can tell you more about manufacturing and business than most college graduates.

  4. Their list misses the key one IMNSHO.

    If you have good 3-D printing (additive andor subtractive), and you have a material that’s both reasonably sturdy and quite recyclable (aluminum), you can start to approach a closed-system.

    Screw printing stuff with “moon rock” for anything but walls. The investment of electricity (yes, a sizable chunk) can get you to aluminum. Casting, wire drawing, CNC, and sintering -just- aluminum can cover a pretty astonishing array of parts.

    1. This is actually much more meaningful in a colony scenario.

      Imagine you have a colony where every system has lots of redundancy (such that failure of any single component is a non-emergency). If most components are designed to be built using a low-footprint industrial base and are designed to be immanently recyclable then you can just reclaim the parts, recycle the material of the bits of the component that needs replacing and then put the refurbished part back in service with little down time. And, more importantly, with very little wastage, which could be the most critical factor of all. Even if the systems end up being less capable than more well made parts the ability to refurbish them without major resource input would be a tremendous win for self-sustainability.

      1. Exactly.

        But the “to Mars” people need to be -thinking- along these lines, instead of NASA’s “How do we make Salisbury steak taste good after seven years?” (aka: every last consumable for the entire trip needs to be precooked and prepackaged) thinking.

        1. Also they need to be thinking about how to build things like life support systems using a very limited industrial base. It’s an interesting combination of extreme efficiency (recycling) and elegance plus sufficient crudeness to enable refurbishment and remanufacturing on a planet with maybe hundreds or thousands of inhabitants, a single machine shop full of tools, and extremely limited production capabilities (e.g. production of only a handful of metals of fairly low quality, no local IC production, etc.) However, if done correctly the Martian industrial base would grow by leaps and bounds year over year.

          One thing a lot of people get wrong about Martian colonists is imagining them as adventurers. Such folks would be useful a tiny minority of the time. What you actually want are highly driven, self-reliant, multi-talented work-a-holics. Folks who are going to get shit done from sunup to sundown, who are going to MacGyver up the very equipment that they depend on for their living. Who are going to go out and establish an entire agricultural base in a matter of years and then expand it massively over time. Imagine that scene from Apollo 13 where they jerry-rig the CO2 scrubbing system, that’s the closest approximation to what life is going to be like for colonists, every day, for years and years (with less peril, most of the time). Tools that are highly flexible will be by far the most useful in that environment.

    2. Lots of titanium on the Moon too. That’d be good for parts needing more strength or heat resistance than aluminum can provide.

      3-D printing of metal parts is currently limited by the surface finish achieveable. I think future low-grav and zero-g machine tools will likely be a combination of 3-D printing (laser sintering) and conventional CNC technologies just as here on Earth. Both conventional machining and grinding yield surface finishes far superior to those of raw 3-D printing. For certain areas of most precision parts, that will be an issue. Featherweight fuel tanks don’t have any critical surface finish issues on most of their insides and outsides, for example, but mating surfaces on flanges do. Lunar machine tools probably ought to exploit grinding to the greatest possible extent. Sintered regolith might make a pretty good grinding wheel.

      The real breakthroughs in 3-D printing will probably be in free-falling habs in LEO, L1/L2, lunar orbit, Mars orbit, etc. Absent gravity, there is little or no requirement for removable support material to be fabricated along with the part so as to make overhangs in the design possible. A lot of earthbound 3-D printed parts wind up needing many times the mass of the finished part laid down in the form of support material that winds up being dissolved away from the “keeper” part. Be nice not to have to do that, or at least nowhere near as much. It would radically improve both the mass efficiency and the fabrication time of a lot of parts.

  5. “I really think we are on the verge of the most exciting era for human spaceflight since the sixties.”

    I hope you’re right this time.

  6. As the technology and experience matures, 3D printing holds the possibility of revolutionizing long-duration space missions. Low mass parts could be created in space, eliminating the need to withstand launch G forces. This alone could significantly lower the mass of space vehicles, especially if they can build structural elements, propellant tanks, spacecraft walls, and internal systems like valves. It was interesting that the article mentioned using this technology to build space suit gloves. That would be huge in places with highly abrasive soils like the moon and Mars.

    Any part created in space could be recreated, eliminating the need to carry spares. While some things like circuit boards could probably be created using 3D manufacturing, it’ll be a while before integrated circuits could be built in space so those will be needed as Earth-created spares.

  7. Delicate parts could be manufactured on-orbit, avoiding the need to design parts to withstand the stresses of launch.

    Sounds like that could be a biggie.

    1. Yes, it’s similar to the advantages of fueling on orbit, because the dry orbital propellant tanks don’t have to take those stresses either. It’s a point that’s often missed even by proponents of orbital fueling.

  8. I really think we are on the verge of the most exciting era for human spaceflight since the sixties.

    Speaking for myself, I think we’re already there, because of SpaceX. (OK, you said “human”, but nonetheless, SpaceX launches have me on the edge of my seat like nothing else today.)

    I remember watching Gemini and Apollo launches back in the sixties. I’m a little too young to remember Mercury, but I read a lot about those flights.

    I didn’t follow SpaceX at first. I didn’t watch any of the Falcon 1 launches or the first Falcon 9 launch. But afterwards, I learned that they had an ignition abort, found the problem, recycled the count, and launched successfully the same day. I had never heard of that ever happening before. I remembered ignition aborts on Gemini 6 and several Shuttle missions, and I was flabbergasted that they went ahead and launched. That was the moment where I really started taking SpaceX seriously.

    So I was watching for the next launch, the COTS 1 flight. It was the first flight test of Dragon; just two orbits and a splashdown. I saw a lot of snarky comments like, “So what? NASA did that 50 years ago”, but I thought of it as a tiny taste of what those pioneering early Mercury flights must have been like, when the whole country stopped in its tracks to follow them. It was the closest that I will ever come to reliving those heady days.

    Then came the long-awaited COTS 2+ flight, the first one to the ISS. That made me feel like a kid again. I have literally never been that excited about a space flight since Apollo. Perhaps the first Shuttle flight might have been that exciting, but my enthusiasm was tempered by the fact that I knew there were no plans to return to the Moon at that time. By contrast, SpaceX has very ambitious plans indeed.

    1. I remembered ignition aborts on Gemini 6 and several Shuttle missions, and I was flabbergasted that they went ahead and launched.

      I don’t know about the SSME, but some engines can’t be restarted without replacing single-use components, because they’d never be restarted in normal operation. The H-1 on the Saturn IB, for example, used an expendable gas generator to start the turbopumps; so, even if they’d found a problem immediately after the engines shut down and and fixed it, they’d have to wait a while to try again.

      Since the Merlin has to restart for satellite launches and stage recovery, they can quickly attempt another launch.

    2. You have company, rickl. I must be a bit older than you. I was six when Sputnik and Explorer I went up, nine when Shepard and Grissom flew; ten when Glenn flew to orbit. I remember watching Echo I and Echo II pass cross the night sky. As Heinlein well put it, “I’ve been space-happy since I was a pup.” I heard about SpaceX early on and watched every launch on streaming video except the first Falcon 1. It is like the 60’s again. The main resemblance is the palpable sense of frequent, visible and accelerating forward progress. SpaceX is moving at a large multiple of the speed of any legacy aerospace major and at only a modestly lesser multiple even of other New Space companies. Exhilarating!

      1. Yes, I was born between Sputnik II and Explorer I. My dad said that I was sitting his lap for Alan Shepard’s flight, but I was too young to remember it.

        The main resemblance is the palpable sense of frequent, visible and accelerating forward progress.

        Well put! Exactly! One didn’t get that sense through 30 years of Shuttle flights.

    3. “SpaceX launches have me on the edge of my seat like nothing else today.”

      Then the launch is scrubbed. It is exciting to watch for sure but I am not waking up early or staying up late anymore.

    4. A three legged stool. Domestic commercial cargo, crew, destination. Once those three are in place and operational, commercial interests are halfway to everywhere.

  9. The reason ‘we are on the verge’ is that space beyond LEO is now going commercial. SpaceX is exciting to watch because they are moving by leaps and bounds but others may make their contributions known soon. Planetary Resources and Deep Space Industries, if they actually get a reasonable mass in lunar orbit, could make everyone rethink their plans.

    Government can only hold us back. Worse if we let the U.N. decide for the rest of us that everyone (meaning no-one) owns space or any piece of rock in it.

    Can you imagine what we could actually do in space if the money being wasted on space wasn’t? Most of the people commenting here could spend it better.

    1. Indeed. Take half a billion dollars, that sort of money is spent all the time in spaceflight (commercial and non). Imagine what happens when you take half of it and put it into R&D and production and then put the other half into buying launch capacity in the $1M/tonne range (which SpaceX can probably achieve within the next 5 years). Now you have $250 mil and 250 tonnes worth of mass to LEO to play with. The mind boggles at the possibilities and the fundamental transformation of spaceflight that will occur. And that’s just one little project. Things are going to get incredibly interesting incredibly fast.

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