Off-planet manufacturing (split from SpaceX)

[kerbiloid]

8 minutes ago, Beccab said:

Sure, but again, why should they build starship there

1. They should build anything there. And a watertower like Starship is such anything. Everything other is more complicated than a steel cistern.

2. They need suborbital and orbital cargo crafts to support the orbital part of the colony and to establish the Martian industrial infrastructure.
Don't forget, that no rover still had passed more than 40 km beyond the Earth.
See their wheels after that and compare to a typical truck mileage.

Spoiler

So, they need methane engines.  Not necessary Raptor, but why not take it as a standard.
So, if they can print a Starship here, they will do it on Mars.

Edited May 30, 2021 by kerbiloid

[tater]

6 minutes ago, kerbiloid said:

The probes do that for decades, and they need ion engines rather than Starship.

Starlink has ion propulsion. Easy to alter them to be probes (better radio and a high gain antenna).

[kerbiloid]

1 minute ago, tater said:

Starlink has ion propulsion. Easy to alter them to be probes (better radio and a high gain antenna).

Starlink still doesn't need Starship, does it?

Only for greater launch rate, of course. Not for propulsion.

[tater]

Just now, kerbiloid said:

Only for greater launch rate, of course. Not for propulsion.

Musk tweeted about using an expendable SS to throw a large number of probes into the outer solar system. Starlinks have ~3.6 km/s dv as it is, so they might be a decent bus for that.

[Elthy]

1 hour ago, kerbiloid said:

Because on the Earth all metallurgy is totally based on coal. Either to chemically reduce the metal (Fe), or as enormous amount of expendable graphite electrodes (Al).

As nothing but Earth ever had algae, so the coal is available only here. Other planets can use only plasma ovens, ionizing the minerals, blowing helium or nitrogen through it, and collectiung the particles.
So they create thin metal dust as primary form of the metal. Which is exactly what the 3d printers use.  

1. Metallurgy works fine without coal, its just the cheapest reducing agent for iron. Aluminium can be made without it, too, you just have to recycle the carbon or win it directly from the martian atmosphere, which you need to do anyway.

2. No matter how you arrive at your raw element, dust or molten metal, its not fit for additive manufacturing. You need to add other elements for alloys and carefully create metall powder with the right diameter, your metall dust is as far from proper material as charcoal is from real printing-ink.

3. If you want to create anything other than complex structures in low quantitys (e.g. a simple I-beam)  you will simply melt the dust and use the same methods as on earth, as printing one of those would take weeks, a gigantic printer and yield lower quality while requiring way more manual labor.

[YNM]

7 minutes ago, Elthy said:

Metallurgy works fine without coal, its just the cheapest reducing agent for iron.

What else have been used / potentially be possible to use on other planets/bodies ? IMO this would be the most important thing in trying to get 'space-age' materials in space.

Also equally important would be to separate the different elements I suppose (like iron from aluminum from silicon or something)

Edited May 30, 2021 by YNM

[kerbiloid]

13 minutes ago, Elthy said:

Metallurgy works fine without coal, its just the cheapest reducing agent for iron.

Metallurgy is totally based on coke, or on "oil coke". It's either a reducing agent, or graphite electrodes.

13 minutes ago, Elthy said:

Aluminium can be made without it, too

1 tonne of aluminium requires to spend 600 kg of graphite electrodes. Made of coke. Made of coal.

13 minutes ago, Elthy said:

Aluminium can be made without it, too, you just have to recycle the carbon or win it directly from the martian atmosphere, which you need to do anyway.

600 kg of carbon per tonne of metal - is "just", of course.

13 minutes ago, Elthy said:

No matter how you arrive at your raw element, dust or molten metal, its not fit for additive manufacturing. You need to add other elements for alloys and carefully create metall powder with the right diameter, your metall dust is as far from proper material as charcoal is from real printing-ink.

By plasma oven you get metal dust for the 3d metal ink composition.

Or you can melt the dust into slabs and need whole industry to roll and cut them instead, which will weight more than the industry's total product.

13 minutes ago, Elthy said:

3. If you want to create anything other than complex structures in low quantitys (e.g. a simple I-beam)  you will simply melt the dust and use the same methods as on earth

Same methods = rolling and cutting.
On the Earth you have millions of customers to buy 1 000 t of rails and screws of 10 000 types which you have produced.
On Mars you need 1 000 t of the rolling and cutting machines to make 10 t of screws and 100 t of rails. A bad idea.

Edited May 30, 2021 by kerbiloid

[YNM]

1 minute ago, kerbiloid said:

By plasma oven you get metal dust for the 3d metal ink composition.

I'm pretty sure there aren't any metal alloys/grade that're the exact same as wherever the regolith happens to be... but idk.

[kerbiloid]

Just now, YNM said:

I'm pretty sure there aren't any metal alloys/grade that're the exact same as wherever the regolith happens to be... but idk.

You should mix the dusts in a mixer.

[YNM]

Just now, kerbiloid said:

You should mix the dusts in a mixer.

Well assuming you can separate the grains of different oxides.

But I think for 3D printing the grains have to be in the alloy form already.

[kerbiloid]

3 minutes ago, YNM said:

Well assuming you can separate the grains of different oxides.

Assuming you have separated the metal ions.

Any ore is prepared ("enriched") first, and this is a whole branch of the mining industry. Operations are mechanical and thermal. Sometimes magnetic (to separate iron particles somewhere).

So, no, there is no problem to separate iron and aluminium. Titanium as well.
And aluminium and magnesium usually used as alloy, so you should adjust the ratio, not separate.

Also you don't need pure alcali metal atoms. Oxides are still good.

Edited May 30, 2021 by kerbiloid

[YNM]

9 minutes ago, kerbiloid said:

Assuming you have separated the metal ions.

Will say I still don't get how we separate out impurities from ores. Though it's kinda hard to imagine us being able to separate say, iron out of regular soil, since if we had been able to do that we'd just have done that straight away...

Regolith are kinda similar, no ?

[kerbiloid]

19 minutes ago, YNM said:

Will say I still don't get how we separate out impurities from ores.

There are no impurities. There are oxides of metals. And of sulfur.

19 minutes ago, YNM said:

Though it's kinda hard to imagine us being able to separate say, iron out of regular soil

Same as it's done for millenia. Crushing, floating, shaking through meshes, electromagnetic sepearation on a conveyor belt, etc. Pure physics. See "ore enrichment" for details.

In case of plasma oven (evaporating the rock, then ionizing it by a shockwave in plasma cloud, causing adiabatic compression and heating), probably electromagnetic separation of evaporated ionized metals is the most common, as it decrease need in the enrichment.

19 minutes ago, YNM said:

Regolith are kinda similar, no ?

"Regolith" is just a common name for dispersed rock covering the solid rock. It's not a mineral name.

No, minerals are different, and more or less same as on Earth. Different concentrations of minerals in different places.
So, mine every metal where its ore is most rich. But as well, you can extract metals from any stone, and (and the most important) from all kind of the colony wastes.
As a result, the metallurgy and the waste recycling get united in one complex plant.

Edited May 30, 2021 by kerbiloid

[YNM]

18 minutes ago, kerbiloid said:

33 minutes ago, YNM said:

Though it's kinda hard to imagine us being able to separate say, iron out of regular soil

Same as it's done for millenia.

Are you saying people could've sent the soil they excavated from digging basements to a steel mill ?

20 minutes ago, kerbiloid said:

34 minutes ago, YNM said:

Regolith are kinda similar, no ?

"Regolith" is just a common name for dispersed rock covering the solid rock. It's not a mineral name.

Well I mean idk if anyone's been mapping where are there ore deposits on the Moon, but until then I guess we should try to do it from the only thing we know and is lying all around the lander/base.

[Nothalogh]

54 minutes ago, kerbiloid said:

On Mars you need 1 000 t of the rolling and cutting machines to make 10 t of screws and 100 t of rails. A bad idea.

Make all the rails and screws anyway

[kerbiloid]

29 minutes ago, YNM said:

Are you saying people could've sent the soil they excavated from digging basements to a steel mill ?

Soil is not rock, and the crust rock is mortly Al, Mg, and Si oxides.

29 minutes ago, YNM said:

Well I mean idk if anyone's been mapping where are there ore deposits on the Moon

https://en.wikipedia.org/wiki/Lunar_resources

29 minutes ago, Nothalogh said:

Make all the rails and screws anyway

On the Earth you have "1 000 000" t of machines, and produce "10 000 000" t of metal goods of "10 000" types.
Anybody anyway buys them, so no problem,

On the Mars you need just "10 000" t of same goods of "1 000" types, but need "100 000" t of machines to roll, pull, and cut.

So, on the Earth it makes sense, but on Mars kills the idea. On Mars it's better to have "1 000" t of 3d printers.

The Earth metallurgy is not scalable down.

Edited May 30, 2021 by kerbiloid

[SOXBLOX]

25 minutes ago, kerbiloid said:

The Earth metallurgy is not scalable down.

Their point is that we don't have to do it the same way on Mars as we do it on Earth.

In the thread I made on using silane as rocket fuel, on of the papers proposed chemical processes for extracting iron, titanium, and magnesium from various types of regolith, either by reduction with hydrogen and oxygen, or carbon compounds, or hydrochloric acid (which would be a functional catalyst, since it would be recovered). The point is, it's absolutely possible.

[YNM]

35 minutes ago, kerbiloid said:

Soil is not rock, and the crust rock is mortly Al, Mg, and Si oxides.

Well is regolith soil then ?

[JoeSchmuckatelli]

1 minute ago, YNM said:

Well is regolith soil then ?

Technically - soil has organics in it, IIRC.

From what I recall - you can smelt iron out of basement tailings - pretty much any soil has been used for bog iron.

[SOXBLOX]

1 hour ago, YNM said:

Are you saying people could've sent the soil they excavated from digging basements to a steel mill ?

You certainly could, provided it contains iron. It's just that processing it is insanely difficult with little reward, compared to extraction from ore.

Heh. Ninja'd by @JoeSchmuckatelli.

Edited May 30, 2021 by SOXBLOX

[magnemoe]

7 hours ago, YNM said:

Correction : It's only possible through automation. You'll never 3D print anything by moving the nozzle with your own hand manually.

And that shows it's pretty complicated as dumb humans can't do it.

This is true for most mass manufacturing of metal parts like stamping or CNC, yes you might have humans move part inn and out and inspect them and stamping is way faster as in you press. 
 

[YNM]

30 minutes ago, magnemoe said:

This is true for most mass manufacturing of metal parts like stamping or CNC, yes you might have humans move part inn and out and inspect them and stamping is way faster as in you press. 

Well yeah to the modern standards they're much better done by a computer. But there was a time when it was manual.

3D print pretty much has only existed today - perhaps the closest we get before computer/automated control is extrusion... one could argue the I-beams coming out of factories *are* printed XD

1 hour ago, JoeSchmuckatelli said:

pretty much any soil has been used for bog iron.

1 hour ago, SOXBLOX said:

You certainly could, provided it contains iron.

Note to self - tunnel building is a form of mining XD

[FleshJeb]

5 hours ago, kerbiloid said:

Because it's on Mars. It's far from the asteroid belt

Former asteroids Phobos and Deimos are right there.

• They almost certainly have water ice.
• They're cheaper to get to than the Moon.
• They're tidally-locked, so you can have Phobos under your feet and Mars in the sky blocking out a significant fraction of the radiation.

Illustrated:

Spoiler

 

[kerbiloid]

8 hours ago, YNM said:

Well is regolith soil then ?

Soil is a mix of rotten organics and dust of crust minerals.
It doesn't contain much iron, so no reasons to mine the iron from the soil.

7 hours ago, YNM said:

3D print pretty much has only existed today

A kind of 3d printing was being used in 1970s - the "powder technologies in metallurgy". Just was more expensive and bulky.

***

You don't need a huge 3d printer to print the whole Starship and buildings like those mushroom-like ant-heaps from the videos previously posted.

All you need is to replace the rolling machines where it's possible.

You should print not the whole assembled rocket, but metal sheets, bars, beams, screws, wire, forms for stamping, hollow shaped bricks for building walls and floors.

With same 3d printer you can print sheets of custom thickness, composition, texture, and size.
So, it can replace a whole workshop of rolling machines.

Just it's much more expensive on the Earth than just buy a sheet rolled by somebody from a cast slab produced out of ore and coke. And much less productive.
But beyond the Earth you don't have the coke, but you have the metal powder.
And your need in metal goods is many times lower than on the Earth, because you don't have billions of people, millions of cars, and so on. 
So, printing the sheets is less expensive than  any other way of manufacturing, while low production is not a problem because you need to build this in spacesuits, and the colony is not a billion of humans.
And you can print exactly that set and amount of details which you actually need to the moment.

You 3d-print stamp forms and the stamp hulls with these forms, from the 3d-printed sheets.
Cut holes and engrave them with a laser machine, not 3d-print every scratch.

Cut screws from the wire probably same, in a laser cutting/engraving machine.

Using metal composition, you mass print shaped hollow brick made of sitalls.
Then you build unpressurised structural constructions of the building, leaving room for pressurised compartments.

You print a rectangular tin sheet of standard size, cut it with a laser, bend into a cylindric ring, like you when build a rocket on the Earth.
Then by stacking and welding such rings, you get the wall part of a metal hull. Then attach top and bottom (stamped from a larger printed sheet with a printed stamp form).
So you get either a tank, or a habitat hull.
Then you put such habitat into the printed brick carcass, fill the empty voulme with regolith, and get the Martian or lunar house.

So, Starship and Falcon are just obvious demo samples for the Martian industry required to build a normal colony.

Edited May 31, 2021 by kerbiloid

[StrandedonEarth]

It seems that zero-gee manufacturing is closer than we think.... https://www.nasaspaceflight.com/2021/09/varda-space-manufacturing/. The plan is to use ISS-proven modules supported by a RocketLab  Photon bus. While the specific product for the mission is not confirmed, the ISS has tested optical fiber production with twenty times the performance of groundside-produced fibers. 

While finding and reviewing this thread, I noticed this:

On 5/30/2021 at 2:45 PM, YNM said:

3D print pretty much has only existed today - perhaps the closest we get before computer/automated control

3D "Printing" is a modern thing, yes. Additive manufacturing, however, is not new. Just look at these beautiful built-up welds on these Saturn V gimbal mounts, done by hand. Same process of adding layer upon layer of material...