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#26 2012-01-20 14:19:11

JoshNH4H
Member
From: Pullman, WA
Registered: 2007-07-15
Posts: 2,526
Website

Re: 3D Printers

Oh, and quick question: Would extrusion molding be quicker if it were done at Mars ambient temperatures, for example by extruding into liquid CO2?


-Josh

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#27 2012-01-23 08:23:46

Glandu
Member
From: France
Registered: 2011-11-23
Posts: 106

Re: 3D Printers

JoshNH4H wrote:

Glandu (Still have the urge to call you El Slapper, even though it's been almost two months that Newmars has been back)-

As always, your expertise in the matter is much appreciated.

Thanks. You can call me el_slapper, or slap, as you want. Maybe I'll update my sig. I just switched pseudos so that there is no database problem if one day the rest of datas is loaded back. (I'm probably dreaming wet, here).

JoshNH4H wrote:

wrt Thermosetting polymers, I suppose the problem is that I lack knowledge of the methods usually used on Earth.  How are thermosetting polymers usually formed into objects in an Earth-based factory?

With molds. Can be throwable low-resistance wooden molds, but you need something solid to keep it in one piece while it "dries". There are many variants, especially for composites(usually a thermoset matrix with a cloth "reinforcement", cloth can be kevlar, carbon, glassfiber...).

In other words, useful only for series. Much smaller than for thermoplastics(where molds for small pieces are steel monsters), yet, for one single piece, usefulness is limited.

JoshNH4H wrote:

I would not be surprised if silicone is not recyclable.  After all, there seems to be little reason why it would be.  Standard procedure will probably be to extract the silicon and either burn the rest (e.g., the methane) or send it back through the chemical production facilities.

can't answer for that, sorry.

JoshNH4H wrote:

I don't doubt that metals will suffice in a wide variety of applications.  They are, after all, stronger, require less energy to produce (per kilo, at least, probably not per liter), and sound like they're much more workable, especially at a smaller scale.  Nevertheless, I'm sure some need for plastics will remain so I would like to have some options available.

yeah, I had a looong post about cable protection. for that you need extrusion. Different variants possible.

JoshNH4H wrote:

Also, it occurs to me that it will probably be impossible to recover the acetic acid when silicone is being used as a caulk.  It happens, I suppose.

Silicones are a special matter. Can't answer here either.

JoshNH4H wrote:

Oh, and quick question: Would extrusion molding be quicker if it were done at Mars ambient temperatures, for example by extruding into liquid CO2?

ahem. "extrusion" & "molding" are contradictory. That's the beauty of the aforementioned 3D printer(even if the final quality is something I have doubts about) : it makes pieces like if they were molded, with extrusion & without mold.

Normally, extrusion makes profiles. Like a window frame, or a cable, or a tube, or a wire..... This thing we have here is the first news I have of dynamically altering the profile while extruding. It has a lot of potential.

Now to answer your question. I did personally extrude tubes(5 cm diameter) at 30/40 cm/second. It works thanks to the extreme viscosity of extrusion-dedicated grades of plastic. Ours was overcrowded with chalk(up to 60% in weight, it reduces a little mechanical resistance, increases somewhat the weight, & lowers prices a lot); without it, it could even go quicker. Mars-like temperatures could help going even quicker(but do we need industrial production rates?), but with risks upon quality(nothing definitive I'd say).

Where I did have doubts, is for thermosets. Those ones need to be heated for solidification instead of cooled down, and the process is slower. Martian cold can't help there.


"I promise not to exclude from consideration any idea based on its source, but to consider ideas across schools and heritages in order to find the ones that best suit the current situation." (Alistair Cockburn, Oath of Non-Allegiance)

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#28 2012-01-23 15:00:15

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 3,827
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Re: 3D Printers

Plastics used outdoors on Mars are going to be susceptible to rapid UV damage,  without some sort of opaque coating.  Indoors,  just like here,  pressurized or not.  TiO2-white or C-black paints work pretty good here,  on kit-built glass-polyester/vinyl ester and glass-epoxy airplanes.

The cold is bad for plastic items,  too.  Most of the materials I know get rather brittle below glass transition temperatures that are not very far below room temperatures here.  Sort of like our winter temperatures.  Mars is a lot colder.  Reinforced plastics would do better in the cold,  but that's not extrudable or 3-D printable.  You're talking hand layup in a mold for that,  like building canoes out of fiberglass.  Whether you bag-compress it or not depends on the materials.  Vacuum-bagging makes really nice carbon-epoxy panels. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#29 2012-01-24 06:08:03

Glandu
Member
From: France
Registered: 2011-11-23
Posts: 106

Re: 3D Printers

GW Johnson wrote:

Plastics used outdoors on Mars are going to be susceptible to rapid UV damage,  without some sort of opaque coating.  Indoors,  just like here,  pressurized or not.  TiO2-white or C-black paints work pretty good here,  on kit-built glass-polyester/vinyl ester and glass-epoxy airplanes.

black carbon is a standard protection against many things, including UV. Of course, your product is black, then. Though I don't know wether it's enough for Mars specific conditions.

GW Johnson wrote:

The cold is bad for plastic items,  too.  Most of the materials I know get rather brittle below glass transition temperatures that are not very far below room temperatures here. Sort of like our winter temperatures.  Mars is a lot colder.

That is heavily dependant on the kind of plastic you are using. Polyprolylene is brittle at 0°C/-10°C. Polyethylene between -80°C & -120°C.

GW Johnson wrote:

Reinforced plastics would do better in the cold,  but that's not extrudable or 3-D printable.  You're talking hand layup in a mold for that,  like building canoes out of fiberglass.  Whether you bag-compress it or not depends on the materials.  Vacuum-bagging makes really nice carbon-epoxy panels. 

GW

Reinforced thermoplastic is still in danger in the cold, if the matrix itself is in danger in the cold. Little less, but I wouldn't take that kind of risks(and needs a huge pressure to be molded). Reinforced thermoset(which is, I think, what you have in mind, correct me if I'm wrong), as you say, also needs a mold.


"I promise not to exclude from consideration any idea based on its source, but to consider ideas across schools and heritages in order to find the ones that best suit the current situation." (Alistair Cockburn, Oath of Non-Allegiance)

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#30 2012-01-24 17:14:21

louis
Member
From: UK
Registered: 2008-03-24
Posts: 5,650

Re: 3D Printers

Glandu wrote:
GW Johnson wrote:

Plastics used outdoors on Mars are going to be susceptible to rapid UV damage,  without some sort of opaque coating.  Indoors,  just like here,  pressurized or not.  TiO2-white or C-black paints work pretty good here,  on kit-built glass-polyester/vinyl ester and glass-epoxy airplanes.

black carbon is a standard protection against many things, including UV. Of course, your product is black, then. Though I don't know wether it's enough for Mars specific conditions.

GW Johnson wrote:

The cold is bad for plastic items,  too.  Most of the materials I know get rather brittle below glass transition temperatures that are not very far below room temperatures here. Sort of like our winter temperatures.  Mars is a lot colder.

That is heavily dependant on the kind of plastic you are using. Polyprolylene is brittle at 0°C/-10°C. Polyethylene between -80°C & -120°C.

GW Johnson wrote:

Reinforced plastics would do better in the cold,  but that's not extrudable or 3-D printable.  You're talking hand layup in a mold for that,  like building canoes out of fiberglass.  Whether you bag-compress it or not depends on the materials.  Vacuum-bagging makes really nice carbon-epoxy panels. 

GW

Reinforced thermoplastic is still in danger in the cold, if the matrix itself is in danger in the cold. Little less, but I wouldn't take that kind of risks(and needs a huge pressure to be molded). Reinforced thermoset(which is, I think, what you have in mind, correct me if I'm wrong), as you say, also needs a mold.

A couple of observations:

1.  I would think we would wish to avoid use of plastics out in the open - surely the primary uses would be indoors to begin with?

2.  One thing we wont be short of on Mars: energy.  If we do use plastic outside, it will probably form part of objects which can be kept heat throughout the sol.


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#31 2012-01-25 03:57:46

Glandu
Member
From: France
Registered: 2011-11-23
Posts: 106

Re: 3D Printers

louis wrote:

A couple of observations:

1.  I would think we would wish to avoid use of plastics out in the open - surely the primary uses would be indoors to begin with?

2.  One thing we wont be short of on Mars: energy.  If we do use plastic outside, it will probably form part of objects which can be kept heat throughout the sol.

1. Well, do you need electric cables outside? Do you need to protect them? Are you able to protect them without plastic?
For the rest I agree. But the specific point of cable protection is really complex.

2. I don't understand. Sun is scarce, solar panels are complex to build on site, nuclear has a few difficulties by itself, & everything in the base will be energy-eating.


"I promise not to exclude from consideration any idea based on its source, but to consider ideas across schools and heritages in order to find the ones that best suit the current situation." (Alistair Cockburn, Oath of Non-Allegiance)

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#32 2012-01-25 18:15:36

louis
Member
From: UK
Registered: 2008-03-24
Posts: 5,650

Re: 3D Printers

Glandu wrote:

1. Well, do you need electric cables outside? Do you need to protect them? Are you able to protect them without plastic?
For the rest I agree. But the specific point of cable protection is really complex.

2. I don't understand. Sun is scarce, solar panels are complex to build on site, nuclear has a few difficulties by itself, & everything in the base will be energy-eating.

1. I suppose this comes back to the usual  question of "Are you talking about early on or later on in the colonisation process?"  Early on, I think it is far more efficient to take the cable to Mars - presumably we will use specialist lightweight materials, cost not being any particular object as far as cabling insulation goes.

Longer term, yes the colony needs to manufacture cabling. In an intermediate development phase, it might be possible to substitute with other materials and procedures e.g. perhaps you could use bamboo or ceramics and bury them in the regolith.

2. I think you have to look at this in context - even not allowing for LENR (which I think will come on stream within the next 10 years) we are talking about a huge energy potential.  Remember, there will only be a tiny population  on Mars for many years. It is relatively easy to get efficient PV panels or nuclear power to Mars, so that each person there can benefit from a huge per capita amount of energy.  Furthermore, it should be relatively easy to manufacture energy generation capacity on Mars - specifically solar reflectors and steam engine generators.  We can afford to be extravagant about external heating where necessary.


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#33 2012-01-26 02:01:45

JoshNH4H
Member
From: Pullman, WA
Registered: 2007-07-15
Posts: 2,526
Website

Re: 3D Printers

Glandu-

With molds. Can be throwable low-resistance wooden molds, but you need something solid to keep it in one piece while it "dries". There are many variants, especially for composites(usually a thermoset matrix with a cloth "reinforcement", cloth can be kevlar, carbon, glassfiber...).
In other words, useful only for series. Much smaller than for thermoplastics(where molds for small pieces are steel monsters), yet, for one single piece, usefulness is limited.

But, you don't need a huge amount of force to get it into the mold?  I was picturing a high-ish pressure needle(Not necessarily so fine as a needle, but similar design.  Call it a hose if you want, you get the idea) injecting molten plastic resin into a mold.  Is that a reasonable mental model for the production of shaped pieces out of thermoset resin?

Also, thank you for your explanation of extrusion vs. molding.  That makes things a lot clearer to me.  I would hazard a speculation that research into themosets might be beneficial to 3d printing, seeing as you can get it to set using a laser or other heating device.

On cables/wiring: Firstly, there is simply no reason to import this.  It requires a simple ability to process metals (I would think Aluminium would be used on Mars in preference to Copper, seeing as it's not too much less conductive and is much more readily available, plus Martians are not going to be sending power over very long distances.  If Copper is discovered I will definitely revise this because Copper is easier to get from ore, but this is not expected AFAIK), as well as the ability to make electrical insulation, which is necessary anyway.  I think we might want to make a distinction between inside and outside, and perhaps a further distinction, when inside, of "wet" or "dry" environments.  These of course present very different challenges in terms of the materials needed to insulate the cables.

Outside, the biggest danger is that someone is going to get electrocuted through their spacesuit when they're trying to manipulate the wire.  Though spacesuits will probably be of the mechanical counterpressure design, which tends to be made of materials which are not conductive of electricity, we don't want to risk it.  Therefore the most important thing is that the insulation be, well, an insulator.  It should also be capable of functioning at low temperatures.  I would suggest that a cloth woven of basalt fiber would be more than sufficient in this function.

Inside, there is of course the worry about fires caused by water penetrating a cloth that is not watertight.  I would suggest that wires in most places are unlikely to see water, but nevertheless it is worth worrying about for all pressurized areas.  I think basalt fiber-silicone composite is perfect for this, seeing as the silicone is easy to form around most anything and is relatively flexible, which is a good thing for wires.

On the smaller topic of UV protection, I would think Carbon would be pretty opaque, but failing that a vapor deposited coating of Aluminium or a Chemically deposited (through Iron Carbonyl) coating of Iron should work.  I see no reason to avoid the use of polymers outside unless there is some actual need to do so.  I don't know what the glass transition temperature of melamine resin is, so I can't comment on this particular point.  It's probably higher than mars temperature, though.  Metal will probably be preferred in most outdoor applications anyway, so it's fairly feasible to avoid the use of polymers outdoors.  On the other hand, seeing as it will find a good deal of use as a sealant silicone will hopefully be able to function with at least one face pointing at Mars.  Silicone won't necessarily be used for its strength as much as for the need of a solid material to keep air or water in, so this may be acceptable so long as its volume doesn't change too much.

With regards to louis' statement that energy will be available in excess:

2. I don't understand. Sun is scarce, solar panels are complex to build on site, nuclear has a few difficulties by itself, & everything in the base will be energy-eating

QFT- Quoted for truth.  Just because the colony will require more energy per capita than Earth does not mean that this energy will be cheaper.  Concentrated Solar Power is significantly more expensive on Earth than coal, gas, or nuclear, but due to a lack of viable alternatives (at least for an early colony; later on there will almost certainly be a switch to nuclear) it will probably be the energy source of choice.


-Josh

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#34 2012-01-26 08:42:44

Glandu
Member
From: France
Registered: 2011-11-23
Posts: 106

Re: 3D Printers

JoshNH4H wrote:

Glandu-

With molds. Can be throwable low-resistance wooden molds, but you need something solid to keep it in one piece while it "dries". There are many variants, especially for composites(usually a thermoset matrix with a cloth "reinforcement", cloth can be kevlar, carbon, glassfiber...).
In other words, useful only for series. Much smaller than for thermoplastics(where molds for small pieces are steel monsters), yet, for one single piece, usefulness is limited.

But, you don't need a huge amount of force to get it into the mold?  I was picturing a high-ish pressure needle(Not necessarily so fine as a needle, but similar design.  Call it a hose if you want, you get the idea) injecting molten plastic resin into a mold.  Is that a reasonable mental model for the production of shaped pieces out of thermoset resin?

That's for thermoplastics. The question was about melamine, a thermoset. Thermoset are far more liquid(therefore you can't extrude them), and don't need steel monsters that thermoplastics require.

JoshNH4H wrote:

Also, thank you for your explanation of extrusion vs. molding.  That makes things a lot clearer to me.  I would hazard a speculation that research into themosets might be beneficial to 3d printing, seeing as you can get it to set using a laser or other heating device.

I'd say it is highly speculative. the risk is to have an unbalanced heating, that would make some parts solid much before others. Result would be an unreliable piece. Current processes require a mold, because a proper heating/solidifying needs time(in minutes) at not too hot temperatures(best thermoset die at 1000°C in 12 s, IIRC. They are used for military missiles, iirc). Some processes even require hours of heating under pressure(autoclave).

At least, thermoplastics cool down & solidify must faster. That's why their potential for rapid prototyping is IMHO superior. Even if this machine found by Louis is probably still far from our specific needs(but info is scarce, & reliable info inexistant).

JoshNH4H wrote:

On cables/wiring: Firstly, there is simply no reason to import this.  It requires a simple ability to process metals (I would think Aluminium would be used on Mars in preference to Copper, seeing as it's not too much less conductive and is much more readily available, plus Martians are not going to be sending power over very long distances.  If Copper is discovered I will definitely revise this because Copper is easier to get from ore, but this is not expected AFAIK), as well as the ability to make electrical insulation, which is necessary anyway.  I think we might want to make a distinction between inside and outside, and perhaps a further distinction, when inside, of "wet" or "dry" environments.  These of course present very different challenges in terms of the materials needed to insulate the cables.

100% agre with that part. Aluminium is heavily used here for medium-powered cables. I did work in a mill making cables for going under the streets & feeding houses. Most of their products were in aluminium.

JoshNH4H wrote:

Outside, the biggest danger is that someone is going to get electrocuted through their spacesuit when they're trying to manipulate the wire.  Though spacesuits will probably be of the mechanical counterpressure design, which tends to be made of materials which are not conductive of electricity, we don't want to risk it.  Therefore the most important thing is that the insulation be, well, an insulator.  It should also be capable of functioning at low temperatures.  I would suggest that a cloth woven of basalt fiber would be more than sufficient in this function.

To be tested...

JoshNH4H wrote:

Inside, there is of course the worry about fires caused by water penetrating a cloth that is not watertight.  I would suggest that wires in most places are unlikely to see water, but nevertheless it is worth worrying about for all pressurized areas.  I think basalt fiber-silicone composite is perfect for this, seeing as the silicone is easy to form around most anything and is relatively flexible, which is a good thing for wires.(.../...)

Inside you've got air. Air can't be 100% dry(or people will be sick). So you need something water-resistant. BTW, why do you want a composite? The interest of fibers outside is that you don't need a f****g plastic/silicone. Once you need it, I'm really not sure of the value of the fibers. If you want to shock-protect your cables, you can round the fiber over the already insulated cable. 1000 times easier.


"I promise not to exclude from consideration any idea based on its source, but to consider ideas across schools and heritages in order to find the ones that best suit the current situation." (Alistair Cockburn, Oath of Non-Allegiance)

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#35 2012-01-27 15:38:43

JoshNH4H
Member
From: Pullman, WA
Registered: 2007-07-15
Posts: 2,526
Website

Re: 3D Printers

Glandu-

For making things out of thermosets, is their viscosity low enough that you can actually pour the resin into the mold, or is it still necessary to apply some small amount of force to get it into the mold?

Given you input, I was clearly wrong about my thermoset suggestion.

I was actually just looking at it earlier, we don't actually necessarily have a way to make Aluminium easily.  The Hall-Herout process, usually used on Earth, would require importing fluorine from Earth.  The fluorine would be a catalyst, but you would need a significant amount of it and it would be expensive.

The only other way that I can think of is to get an alkali metal, probably sodium since it's the most common, and use it in what would essentially be a smelting reaction.  This is actually beset with similar issues, in that most alkali compounds have fairly high (though not as high as Al2O3) melting points, which makes it hard to get your Na.  NaOH is an exception, but attempts to electrolyze that will just lead to solid Na2O and water.  Something to keep in mind is that NaCl has a lower melting point than Cryolite, which is usually used to produce Aluminium.  This uses about 40% more energy than going directly from Aluminium Oxide, but on the plus side requires no imports.  Also, it produces Sodium Oxide, which can be recycled to produce valuable and highly useful NaOH, albeit at a high energy cost.  You can also bubble the produced Chlorine through water to make HCl. 

While some experimenting would have to be done, there's no particular reason why using basalt fiber cloth would not work outside.  There's nothing conductive out there and nothing that could corrode the wires to any significant degree, especially not in the dry cold.

Inside is a different story, but water in the air does not make the air conductive.  It would really only be a problem if the wire were at a significantly lower temperature than the air surrounding it.  That said, indoors it's always a good idea to protect from water, and seeing as the actual use of silicone in terms of volume will be pretty minimal the additional safety is definitely worth it.

I don't think that the composite will be as difficult to make as you suggest in this case, because you can, to my understanding, basically paint the silicone on.  On the other hand, my suggestion that you would use a composite was mostly due to my not thinking about it.


-Josh

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#36 2012-01-27 17:04:45

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 3,827
Website

Re: 3D Printers

Outside electric cables on Mars:

Use a UV-tolerant C-black plastic sheath over normal Earth-type cable insulation.  You can label your wires to tell them apart,  even if everything is black in color:  that's just tags.  Keep the cable spool warm while you're laying cable (not so very hard to do).  Once it's laid,  don't move it again.  Then it does not matter whether the cable insulation gets brittle if it gets cold:  it only breaks if you move it.  Plus,  the normal insulation is proof against groundwater and frost. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#37 2012-01-28 00:08:32

JoshNH4H
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From: Pullman, WA
Registered: 2007-07-15
Posts: 2,526
Website

Re: 3D Printers

GW-  The problem with an early, mostly self-sufficient Martian colony is that it won't be able to produce the wide range of materials that modern industrial society can.  I would imagine that Basalt Fibers would not change their behavior much at lower temperatures.

I don't believe groundwater or frost will be such a big issue.  The colony won't be built on ice, after all.


-Josh

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#38 2012-01-28 07:46:11

louis
Member
From: UK
Registered: 2008-03-24
Posts: 5,650

Re: 3D Printers

JoshNH4H wrote:

GW-  The problem with an early, mostly self-sufficient Martian colony is that it won't be able to produce the wide range of materials that modern industrial society can.  I would imagine that Basalt Fibers would not change their behavior much at lower temperatures.

I don't believe groundwater or frost will be such a big issue.  The colony won't be built on ice, after all.

I'm a fan of using formed basalt where we can e.g. for kitchenware.

I recall that you need v. high temperatures to melt basalt...and I instintively think it will be cold-resistant. Prompts me to ask: is there a relationship between materials that need to be heated to a v. high temperature to melt them being also able to maintain integrity at v. low temperatures?


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#39 2012-01-28 18:57:46

JoshNH4H
Member
From: Pullman, WA
Registered: 2007-07-15
Posts: 2,526
Website

Re: 3D Printers

I did a search for "Formed Basalt" and couldn't find anything.  Do you have any references saying that formed basalt has been produced anywhere, either experimentally or industrially?  Something else to keep in mind that melting rocks and then allowing them to resolidify will often lead to a glassy substance with inferior physical properties.  For a lot of things we won't need super-good properties, but we're potentially talking materials which aren't much better than powder.  Melting is also potentially a fairly energetically intensive process.  Maybe something like pumice.

I actually really like the idea of using sintering to make bulk materials, especially out of base materials (e.g., materials which require very little energy input to produce, such as plain old regolith)  To sinter, you take some material, and turn it into a powder.  You then heat it to a temperature below its melting point for a while, which actually causes what is essentially diffusion, and forms all of the grains together into a single object.  The object is somewhat porous but fairly strong; I would imagine of similar strength to the material of which the grains are made.

I can't say why, but I had that same feeling about Basalt Fiber as well.  However, seeing as "feelings" of this kind are far from authoritative, I googled it.  It turns out that basalt fiber is in fact fully usable to temperatures significantly below those present on Mars, even on the coldest of nights way up at the poles.  Source.

High melting point is reflective of strong intermolecular bonds.  Decreasing strength at low temperature is reflective of... free electrons, maybe?  I'm not really sure, actually.  It is my understanding that the phenomena are not strongly related.


-Josh

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#40 2012-01-28 19:27:01

louis
Member
From: UK
Registered: 2008-03-24
Posts: 5,650

Re: 3D Printers

JoshNH4H wrote:

I did a search for "Formed Basalt" and couldn't find anything.  Do you have any references saying that formed basalt has been produced anywhere, either experimentally or industrially?  Something else to keep in mind that melting rocks and then allowing them to resolidify will often lead to a glassy substance with inferior physical properties.  For a lot of things we won't need super-good properties, but we're potentially talking materials which aren't much better than powder.  Melting is also potentially a fairly energetically intensive process.  Maybe something like pumice.

I actually really like the idea of using sintering to make bulk materials, especially out of base materials (e.g., materials which require very little energy input to produce, such as plain old regolith)  To sinter, you take some material, and turn it into a powder.  You then heat it to a temperature below its melting point for a while, which actually causes what is essentially diffusion, and forms all of the grains together into a single object.  The object is somewhat porous but fairly strong; I would imagine of similar strength to the material of which the grains are made.

I can't say why, but I had that same feeling about Basalt Fiber as well.  However, seeing as "feelings" of this kind are far from authoritative, I googled it.  It turns out that basalt fiber is in fact fully usable to temperatures significantly below those present on Mars, even on the coldest of nights way up at the poles.  Source.

High melting point is reflective of strong intermolecular bonds.  Decreasing strength at low temperature is reflective of... free electrons, maybe?  I'm not really sure, actually.  It is my understanding that the phenomena are not strongly related.

Well "formed basalt" might not be the correct term but I have definitely read about basalt vessels formed by melting the original basalt. I recall it is an East European specialty. I am sure when I have found the reference, you will apologise for the ever-so slight note of incredulity in your post! LOL

I think the basalt objects were things like bowls - I would accept it might not be much use in say producing an eating fork.

Oh good news that basalt fibres keep their integrity at v. low temps. smile


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#41 2012-01-28 22:00:29

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 3,827
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Re: 3D Printers

UV-protected polymer-insulated electric cables:  Sorry,  I was thinking more of modified supplies brought from Earth to make the initial installation. 

Basalt fiber?  Can you weave this into a cloth?  If so,  it might be possible to sleeve metal wire with it as an insulation,  resembling the really-old fabric insulated wires no one sees anymore,  except in older-model electric stovetop cookers.  Those are asbestos-fiber fabrics.  Would basalt be an insulator,  or is it too conductive to serve?  I honestly don't know.

Also,  would basalt fiber pose the same inhalation hazard that asbestos fiber and fiberglass pose?  Does anyone know? 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#42 2012-01-29 06:28:54

louis
Member
From: UK
Registered: 2008-03-24
Posts: 5,650

Re: 3D Printers

GW Johnson wrote:

UV-protected polymer-insulated electric cables:  Sorry,  I was thinking more of modified supplies brought from Earth to make the initial installation. 

Basalt fiber?  Can you weave this into a cloth?  If so,  it might be possible to sleeve metal wire with it as an insulation,  resembling the really-old fabric insulated wires no one sees anymore,  except in older-model electric stovetop cookers.  Those are asbestos-fiber fabrics.  Would basalt be an insulator,  or is it too conductive to serve?  I honestly don't know.

Also,  would basalt fiber pose the same inhalation hazard that asbestos fiber and fiberglass pose?  Does anyone know? 

GW

I've never heard of basalt being woven to make clothes. I think it's used to make a glass fibre material. Yes, I think it does pose an inhalation threat, but not as severe as asbestos is how I remember it.  I think you normally coat glass fibre to reduce or eliminate the inhalation threat.

I think you can melt basalt and re-form it, but I need to find the link.

Last edited by louis (2012-01-29 12:33:56)


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#43 2012-01-29 06:33:07

louis
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Re: 3D Printers

This is an interesting link to the potential of basalt...


http://2011industrial.alternate-healing … asalt.html


Will need to read that some more and absorb it.


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#44 2012-01-29 10:48:19

GW Johnson
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Re: 3D Printers

Louis:

I went and looked at the link.  Very intriguing.  Cold structural blocks and tiles I can see us mining from basalt provinces.  But for fiber,  why go to the trouble of melting it?  Why not catch it liquid coming out at the mid-ocean ridges,  and use the sea to chill the filaments solid as you extrude them?  Sounds like some sort of undersea robot materials-harvesting plant to me.  Probably self-transportable as a submarine vehicle. 

The active lava flows hitting the sea from Hawaii I think are basaltic,  too.  There ought to be a lot of volcanic basaltic lava harvestable all over,  already liquified by mother nature here on Earth.  Not all volcanoes are basaltic,  but many are.  On Mars,  that's another problem.  I don't recall any reports of active volcanism reported there. 

Intriguing idea,  though.  If it can be used as a glass fiber replacement,  then cloth can be woven from it. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#45 2012-01-29 14:18:54

louis
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Re: 3D Printers

JoshNH4H wrote:

I did a search for "Formed Basalt" and couldn't find anything.  Do you have any references saying that formed basalt has been produced anywhere, either experimentally or industrially?  Something else to keep in mind that melting rocks and then allowing them to resolidify will often lead to a glassy substance with inferior physical properties.  For a lot of things we won't need super-good properties, but we're potentially talking materials which aren't much better than powder.  Melting is also potentially a fairly energetically intensive process.  Maybe something like pumice.

I actually really like the idea of using sintering to make bulk materials, especially out of base materials (e.g., materials which require very little energy input to produce, such as plain old regolith)  To sinter, you take some material, and turn it into a powder.  You then heat it to a temperature below its melting point for a while, which actually causes what is essentially diffusion, and forms all of the grains together into a single object.  The object is somewhat porous but fairly strong; I would imagine of similar strength to the material of which the grains are made.

I can't say why, but I had that same feeling about Basalt Fiber as well.  However, seeing as "feelings" of this kind are far from authoritative, I googled it.  It turns out that basalt fiber is in fact fully usable to temperatures significantly below those present on Mars, even on the coldest of nights way up at the poles.  Source.

High melting point is reflective of strong intermolecular bonds.  Decreasing strength at low temperature is reflective of... free electrons, maybe?  I'm not really sure, actually.  It is my understanding that the phenomena are not strongly related.

Here's  a link to a paper on casting basalt as you cast iron.


http://www.cbpengineering.com/pdf/Mater … ptive).pdf

So I think it could be used to make vessels and possibly tools of various kinds.


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#46 2012-01-29 14:28:09

SpaceNut
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Re: 3D Printers

Sounds like Basalt is an early on material for insitu useage but on a scale of 1 to 10 where does it fit in the bigger skeem of things that we need fro insitu resources....

Any thoughts on a mineral/ materials list of priority for mining?

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#47 2012-01-29 15:31:50

louis
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Re: 3D Printers

SpaceNut wrote:

Sounds like Basalt is an early on material for insitu useage but on a scale of 1 to 10 where does it fit in the bigger skeem of things that we need fro insitu resources....

Any thoughts on a mineral/ materials list of priority for mining?


Here's one I prepared a little earlier smile :


(i) Water.  The base will be located close to a water source (probably within 2 kilometres of a large glacier). One of the first tasks of the colonists will be to find a good access point to this glacier and a safe route back to the base along which the DAG vehicle can move with relative ease.

(ii) Atmospheric extraction  The atmosphere will be extracted and concentrated. It will be used with water (itself divided into hydrogen and oxygen) to create methane and to isolate oxygen. Carbon will also be isolated for use in industrial processes.

(iii).  Iron ore  Iron ore is ubiquitous on Mars. Finding a source of iron ore should not present problems but colonists will be keen to find a source with a high concentration – at least 30% so as to improve the efficiency of the smelting process.

(iv).  Silica  Deposits of silica are widespread on Mars.  This material is essential to the production of glass on the planet.

(v)  Aluminium  Aluminium is an extremely useful and malleable metal and it will be a very useful resource for the colony. Rolled aluminium will be used to make reflective foil to be used as part of the Solar Energy Facility.

(vi)  Basalt This volcanic rock will be useful to the colony. It can be used to create ceramic vessels and tools. It can also form the basis for rockwool and glass fibres.

(vii) Calcium carbonate Deposits of calcium carbonate are thought to exist on Mars although they are thought to be much rarer than

The following might  be among the key manufactures produced by the Mission One Colonists:-

•    Metal containers (75kgs)
•    Metal tools and kitchen utensils (30kgs)
•    Mars bricks (120,000 kgs)
•    Mars cement  (20,000 kgs)
•    Glass (100 kgs)
•    Reflective foil  (500kgs)
•    Stirling engines  (500 kgs)
•    Ceramic vessels and tools  (300 kgs)
•    Hydroponic equipment (growing platforms, rockwool)
             (100 kgs)
•    Fibreglass vessels  (40 kgs)


Some food for thought there!

I put in a large figure for Mars bricks and cement because I envisage the colonists constructing dwelling space for those who follow after them...I guess that would be mostly loose Mars top soil beign used there - scooped up by a digger.


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#48 2012-01-29 16:49:18

SpaceNut
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From: New Hampshire
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Re: 3D Printers

The first list of life support is key with water and atmospheric creation for sure.

The list of construction materials a future via insitu processing I think is with Mars bricks, Mars cement & Glass at the top of the second list.

The last list is the wish list for a future which is the Iron ore, Basalt, Aluminium, Calcium carbonate Deposits and other minerals such as sulfur, magnesium....

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#49 2012-01-29 23:53:39

JoshNH4H
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Re: 3D Printers

Louis-

Firstoff, apology definitely given.  I was dubious in part because I remember having discussed Basaltic glasses with Midoshi at least once and finding that their strength was inferior.

I'm not sure I trust the first link.  It makes a lot of claims that are quite grandiose and not really evidence based.  The second one seems pretty solid, though, even if it doesn't have too much information.  There doesn't seem to be that much out there on cast basalt, even though it is clearly a real thing.  It'll probably be quite useful for crushing rocks and the like, which there will be a pretty significant demand for.  Hardness on the mohs scale is supposed to be 8.5, which is pretty good.  I don't know if a close analysis will show that it's better for higher strength applications while sintered regolith will be better for low strength applications, or it makes more sense to just use cast basalt for everything.  I'm actually leaning towards cast basalt, seeing as the properties of sintered regolith are apparently heavily dependent on the precise conditions of manufacture, which means that the actual strength of the product will probably be pretty variable.

I should note that, unsurprisingly, the properties of cast basalt seem to be essentially similar to a brick or a rock.  I might suggest that there is a chance that cast basalt will be found to be preferable to bricks.  Including the energy of boiling the water inherent to brickmaking, the energy required to make each will be similar (I know you believe that there will be a near limitless supply of cheap energy available to the colony but I am somewhat skeptical, seeing as equivalent methods of generating energy on Earth are usually on the expensive side, with electrical energy being about 2-3 times as much as the [US] national average).

Likewise, I have a list prepared of the materials which I consider to be really vital for the survival of the colony and which between them can conceivably constitute all but the most minor solid materials needed for the colony.  These are:

-Bricks
-Basalt Fiber
-Iron
-Steel
-Aluminium
-Silicone (e.g., the polymer)
-Concrete or Cement
-Glass
-Melamine Polymer
-Melamine-Basalt Fiber composite
-Carbon
-PVAc Polymer (for glues and other applications)
-Plasticizer for Melamine polymer
-Magnetite/Some kind of magnetic material
-Cast Basalt/Sintered Regolith/Some kind of Ceramic

This list is by no means mutually exclusive to louis's, it just looks at it from a different angle.  I do believe I saw something at some point about a concrete which did not need calcium.  That would be ideal.  I'll take a look tomorrow.

Last edited by JoshNH4H (2012-01-30 00:02:40)


-Josh

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#50 2012-01-30 00:43:56

JoshNH4H
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From: Pullman, WA
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Re: 3D Printers

Also, it seems I forgot to reply to GW.  My apologies.

GW Johnson wrote:

UV-protected polymer-insulated electric cables:  Sorry,  I was thinking more of modified supplies brought from Earth to make the initial installation.

No problem whatsoever.  Usually, when I'm talking in life support, it's in the context of a colony of about 500-1000 people, largely self-sufficient.  The goals IMO would be to have 10% population growth per year, about 15% economic growth per year (I know this sounds extremely high but I would be glad to elaborate on my thoughts in another thread if anyone is interested), as well as a 5% growth each year in standard of living (e.g, slightly faster than per person economic growth, seeing as 15% economic growth with 10% population rise each year is 4.5% per capita economic growth).

I was always vaguely aware that it could be confusing as to what time period we were talking about.  I hope this clears it up, at least a little bit.

Basalt fiber?  Can you weave this into a cloth?  If so,  it might be possible to sleeve metal wire with it as an insulation,  resembling the really-old fabric insulated wires no one sees anymore,  except in older-model electric stovetop cookers.  Those are asbestos-fiber fabrics.  Would basalt be an insulator,  or is it too conductive to serve?  I honestly don't know.

Also,  would basalt fiber pose the same inhalation hazard that asbestos fiber and fiberglass pose?  Does anyone know?

This website, which I linked to before, is a great reference on the properties of basalt fiber and what can be done with it.  Basalt fiber is most definitely an insulator.  And I was going for exactly what you mentioned in terms of cloth insulation.  Cloth is entirely possible by the way, just scroll down a bit on the page I linked to. 

According to the Wikipedia article on Basalt Fiber, the strands are made large enough so that there is not an elevated cancer risk from inhalation, unlike asbestos.

And, very interesting idea about using volcanoes to make basalt fiber.  Sounds like a good one, though this is not something which I consider myself to know a good deal about.  I think we would see basalt fiber displacing glass fibers in most all applications, with the possible exception of fiber optics, which may not be used at all in an early colony.


-Josh

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