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Maybe this is not possible to answer, but I was hoping there was some reliable information available on this.

It seems to me that the SpaceX Starship rockets have sort of a homemade quality to them, like they were made in someone's garage with basic tools, vs even some of SpaceX's other rockets. They are not painted, just bare metal it seems, and they also don't look as smooth and streamlined.

Is there a specific reason for this, like keeping costs down, or speeding up production? Is it just a fundamentally different way these are constructed? Maybe this is just my untrained eyes, too.

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    $\begingroup$ Hm. I imagine the final Starship will look more refined. The whole design is still very much in development and every prototype is probably designed to be built quickly for testing so they can go iterate on the design and turn around quickly for new tests. The whole vessel will probably still look unusual in the end, but it will seem more "finished', I want to say? $\endgroup$ – user39728 Mar 16 at 18:27
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    $\begingroup$ Why go to the trouble (and expense) of making them pretty, when - on experience to date - they're just going to blow up soon after you launch them? $\endgroup$ – jamesqf Mar 17 at 5:14
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    $\begingroup$ Are we talking about the test versions of the self-landing rockets that have been going up lately? Because those things are being built in the knowledge that them smashing into the ground or blowing up is a likely outcome. $\endgroup$ – Flater Mar 17 at 10:17
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    $\begingroup$ It's not just starship philandgarth.com/wp-content/uploads/2019/06/… $\endgroup$ – Charles Bamford Mar 17 at 18:45
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    $\begingroup$ Have you seen the Space Shuttle Enterprise? Or the Russian Buran shuttles? Or basically any prototype spacecraft or even just prototype aircraft? The first drafts are always a bit sketchy looking. $\endgroup$ – Darrel Hoffman Mar 17 at 20:39
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It seems to me that the SpaceX Starship rockets have sort of a homemade quality to them, like they were made in someone's garage with basic tools

That is because they are!

The "zeroth" prototype, Starhopper was built from November 2018 to March 2019 literally in a dirt field in Texas, in the open air. When Elon Musk announced in December 2018 that SpaceX was abandoning carbon fiber as the construction material and switching to stainless steel, he also announced that they had already been building a prototype test article for several weeks.

Despite the fact that they were building Starhopper out in the open, in a field, on the side of a public road, a lot of people did not even realize that what they were building there was a spaceship prototype. The mental disconnect between what they were seeing and what their mental image was of how "spaceship are supposed to be built" was just too big for them to comprehend. Spaceships are built in cleanrooms by people in white coats with facemarks and hairnets, not by a hired tank welders in a dirt field on the side of a road!

And yet, that is exactly what SpaceX did. Including the tank welder part: according to the logos on the side of their trucks, Starhopper was at least partially built by contractors who normally build water towers. (Which is where the "flying water tower" joke comes from and why it is so delightful that SpaceX actually did turn Starhopper into a water tower instead of scrapping it.)

In the beginning, there was only a dirt field and a tent for workers to store equipment and parts in:

SpaceX Starhopper production site, Boca Chica, TX, USAVideo by Austin Barnard

They didn't even have a windbreak or a way to secure the nosecone, which is why Starhopper flew without one: it was blown over and destroyed by the wind.

Over time, SpaceX added more tents, a windbreak, the midbay, and the highbay, they hired their own welders, they bought welding robots, they switched to a different alloy of stainless steel, they are developing their own alloy of stainless steel, and so on. So, each new prototype actually looks better than the last one.

But, in some sense, they are not even building Starship prototypes. One of Elon Musk's mottos is "Build the machine to build the machine", and that is what they are doing down there. You can almost think of it like the factory is the prototype, and the Starships are just a by-product. (Which is for example why they partially built SN 12–14 and then scrapped them again without ever testing them).

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  • $\begingroup$ To be fair, they did have the nosecone anchored, the wind broke the mooring blocks. (twitter.com/elonmusk/status/1088088320767217664) $\endgroup$ – Christopher James Huff Mar 17 at 23:01
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    $\begingroup$ Breaking the dependence on a cleanroom is a deliverable in its own right. Otherwise what are you supposed to do off-planet? Call a tow-truck? $\endgroup$ – Peter Wone Mar 18 at 0:36
  • $\begingroup$ Thank you. These were all great answers, but somehow I found yours the most interesting and on point to what I was looking for. $\endgroup$ – PhilippNagel Mar 19 at 0:11
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    $\begingroup$ "Build the machine to build the machine" is how it's done, no need to make a motto of it. Should have called the Starship the "Bonadventure" after the sloop-built-up-from-zero (well, with a box of useful goodies) in Jules Verne's The Mysterious Island. $\endgroup$ – David Tonhofer Mar 19 at 21:18
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So there are probably several things about which you are referring.

They mostly stem from the same issue, which is using Stainless Steel for the hull of the vehicle. This has benefits that other questions have addressed.

Why switch Starship from composite to Stainless?

First off, they do not paint it, since stainless does not really need paint (Though they did paint the mock up for the Lunar lander "Human Landing System" white. In that case, they would paint it white to help with temperature control while sitting on the lunar surface. Or else just to make NASA happy since they like white vehicles).

Also, finding paint that does not flake/burn off during high speed flight is non-trivial, (as the X-15 project discovered) and at least for now, they are not flying at high enough speeds to be worth figuring it out. (Era of SN8-11 flights. SN-15 may go faster/higher).

The welds started off very rough looking, as they did manual welding to both form the rings, and to join the rings, basically in a field. Then they added in new tents with automated welders and the quality (determined by success at pressure tests, and lack of pops) or at least visual quality has been improving with each iteration of the Starship prototypes.

Additionally, the skin looks pretty wrinkled, until they pressure test it at which point the skin puffs or expands just enough to smooth out a fair bit of the wrinkles. Then they detank and it gets a bit wrinkled again.

Elon has tweeted that they have or are about to get a planisher, a device to smooth welds out as well.

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    $\begingroup$ So we are really watching them figure out how to build these better each time a new one is made? Pretty cool. $\endgroup$ – PhilippNagel Mar 16 at 16:37
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    $\begingroup$ @PhilippNagel Literally. It is awesome. $\endgroup$ – geoffc Mar 16 at 17:55
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    $\begingroup$ It's also not quite as wrinkly as it looks. It's shiny, so every little ripple stands out. $\endgroup$ – Christopher James Huff Mar 16 at 23:18
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    $\begingroup$ @PhilippNagel That's what some people don't get about the test flights. We're not watching tests to certify the equipment, we're watching a series of science experiments. $\endgroup$ – slebetman Mar 17 at 3:26
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    $\begingroup$ That seems to be the difference between SpaceX and the state of the art in high tech engineering. Other people use test flights to verify that things work as designed, SpaceX uses them to break stuff because it was designed wrong. As an analogy, back in the 1970s aircraft engine manufacturers typically built maybe 25 prototype engines, and expected to self-destruct 20 of them by accident. In the 2020s, you have to make a very good case for wanting 5 prototype engines rather than 4, and nobody expects any of them to self destruct. $\endgroup$ – alephzero Mar 17 at 4:23
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It’s important to keep in mind what SpaceX is trying to achieve here and follow its logic. Their goal is to make humanity a multi-planet species and build a self sustaining city on Mars. And this is not just a sound bite as so many company goals are, this really is what SpaceX are about. To achieve this goal it must be practical, both in engineering and financial terms and financial practicality is probably the harder part and drives many decisions SpaceX make.

They will need a huge number of ships and most of them will be used on multiple missions so the ship must be reusable, robust and must be cheap to manufacture and cheap to fly*. This was at least in part why carbon fibre was eventually rejected – it’s just too expensive. Stainless steel is suitable and relatively cheap. It’s also fairly easily assembled by welding and robust which are ideal properties.

SpaceX have looked at assembly processing and concluded that it is not necessary to build a giant expensive clean room and that it would be cheaper, easier and practical to assemble large parts outside. So that is what they have done. They have probably also figured out that making a Starship look pretty will cost money for little financial gain, so they don’t do that.

But perhaps even more importantly these are early prototypes and there is even less benefit in making them look pretty. Consequently they are what they are, built as cheaply as possible to do the job they are intended for (collect flight data and act as production pathfinders). As time goes on they will gain experience in welding and find process improvements which will help Starship look less rough and ready. They may also need to use a thinner gauge steel which may help.

I expect to see Starship slowly improve in appearance as time goes on, but it may always have a slightly rough look about it because it doesn’t need to look pretty.

  • This is also in part why Raptor is fueled by liquid methane - its very cheap.
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    $\begingroup$ It's not so much the cost of the fuel as the cost of the handling--liquid hydrogen is a pain to work with! $\endgroup$ – Loren Pechtel Mar 17 at 3:47
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    $\begingroup$ @WernerCD: I expect the number of welds to reduce as well. Right now, the only reason for why the size of the rings is what it is, is that this is the largest you can buy on the market. But, SpaceX wants to build thousands of Starships, at which point they have enough "pull" to get suppliers to produce larger ones. Actually, SpaceX's metallurgy department (yes, they have such a thing) is developing a custom stainless steel alloy just for Starship (and the Tesla Cybertruck), so in the end they might just produce it themselves. $\endgroup$ – Jörg W Mittag Mar 17 at 6:28
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    $\begingroup$ Also paint has weight. That much paint has quite a lot of weight. Things don't rust in space. The best way to make a spaceship look good is to put it in orbit. It's impossible to look bad against the crescent of the Earth. $\endgroup$ – Peter Wone Mar 18 at 0:29
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    $\begingroup$ I remember reading many years ago that at least one airline did not paint their planes (i.e., mostly bare metal, just name/logo painted) because of the weight == fuel savings. $\endgroup$ – manassehkatz-Moving 2 Codidact Mar 18 at 2:10
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    $\begingroup$ Tangentially related, the Eiffel tower gets repainted fairly routinely, and the total mass of the paint is pretty non-trivial. Something like 60 tons. Starship and most spacecraft are significantly smaller, but the cost of sending mass into space on Dragon is over 2,700 dollars for just a kg ( used to be 54k on space-shuttle). Every gram saved on paint is nearly 3 dollars of the budget. $\endgroup$ – Ruadhan2300 Mar 18 at 8:55
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I've worked in Aviation Maintenance since 1988. Commercial aircraft/spacecraft are made in a factory, most of the parts are stamped out with dies and presses made specifically for that part, with no seams and bending/shaping all automated. And they are painted. Paint covers a lot of blemishes, just like makeup does on people. If you ever get chance to get close up to the outside of anything that flies, you will see it is not quite so pretty, and the seams and rivets and patches are able to be seen.

I am sure once SpaceX puts a craft into full time production they will produce much prettier products. It was American Airlines that did not paint their aircraft to save on fuel. But they polished them constantly, and finally made the decision to start painting the fuselages of their aircraft due to corrosion problems, the main reason for painting metals.

Stainless steel going into outer space regularly will require paint as well, as it can be made to help reduce the radiation in outer space coming through the hull and the threat of corrosion. Stainless steel can still corrode. I like the idea of using stainless steel though, the extra weight will be negligible when going from the moon to Mars, but will need more fuel to get out of earth's atmosphere.

Any thing that will be reused often will benefit from a steel hull, and new alloys are being developed. Now we just need transparent aluminum for the windows.

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  • $\begingroup$ Rats! If it were still April 1st I'd ask When will we finally have transparent aluminum spaceship windows? $\endgroup$ – uhoh Apr 3 at 4:14
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in old race cars terminology "paint dont make it go"!

unless you have actually built prototype anything (not that that is a big deal) its hard to explain. all the iterations of design start with an idea, which lead to a finished product evolved from the idea. things is, if you had the pristine space vehicles (that were lost) lined up on the ground that you could look at, you'd see this evolution. trouble is rockets tend to self destruct when they fail or crash.

if they did survive,, you would see the form following function.

in the car industry for instance, the vehicle starts with an external design and once that is approved, the internals are added.

happens with many things. trouble is thst is "bass akwards"

the need for complex re-engineer of parts to fit ever changing n spaces is what drives the parts industry and why GM for instance might make 20 or 39ndifferent water pumps, or axles, or seats or whatever.

spacecraft are built for two things, keeping occupants relatively safe and reaching an intended destination.

so looks aren't so important as "what's under the hood" so to speak.

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    $\begingroup$ What does this mean: trouble is thst is "bass akwards"? Also, in English, sentences begin with a Capital letter. Could you please correct all your other errors. $\endgroup$ – Fred May 1 at 17:14

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