Basalt Rhyolite construction? 3d printing your own island

(Chris) #1

I started thinking about how 3d printing a seastead might work and this is what I came up with.

First, to 3d print base and all this would be something that you would need to do in shallow water. Most likely on a seamount then.

Bottom up construction would need you to somehow displace water to get whatever you are adhering to, to stick together. This would mean you’d need some kind of vacuum chamber as big as what you were forming and have to seal it to the seabed in some way. Doesn’t seem realistic.

For top down construction, unless you are in really really shallow water, what ever you are building is probably going to be too heavy to lower to the bottom unless it is a hollow caisson and then why not just build it on land and float it.

But what if you could lower as you were building?

Here’s my idea. This is what molten basalt looks like when you pour it into water.

Notice how it pours pretty straight until steam from the bottom forces it to curl? The bottom also forms pillow lava much like under water volcanoes.

Well, if you are pouring from enough distance it should be cool before it hits bottom so no pillowing and no curling. You would need to pour at an exact continuous speed to keep it from bulging or breaking though. That shouldn’t be real hard since it’s pretty viscous. The steam pressure should be equal on all sides. So what you would end up with in calm water would be an obsidian like basalt rebar from top to bottom. Of course there will be some current even on a seamount, so it would look more like a bent or diagonal rod when you are done depending on the speed of the current.

Well it doesn’t have to look pretty as long as it is functional so over-pouring, so it blobs up, would give you something that looks like an inverse cone or under water volcano by the time you are done. The more you pour in the same spot, the wider it would get. You could pour it to look just like the picture and it would work fine.

Basalt is pretty common. You can buy it in powder form. To melt enough to get the equivalent of
of a 50 cubic meters would take about 300 tons if my math is right. (6 tons per cubic meter is a rough guess) The only ton price I could find was for snow sand basalt and not powder but it was $8.50 so lets just say $20 a ton to be safe. That’s $6000 in materials for forming an island made out of the same material as Hawaii. And you are going to have to pay for it to be hauled to you and for the ship to wait while you melt and pour it.

Now there is a big cost I am leaving out. To melt it, you are going to need a big hopper and a furnace. There are ships with conveyors that can dump it into your hopper. Since you are dumping in a big blob, you can dump it as fast as you can melt it. For melting, you’re gonna need plasma torches and a tap. I’ve already seen a system that uses 2 torches and can melt 200 kg an hour, so lets put in 10 torches and melt a ton an hour. It would take you 300 hours to melt and dump it. That’s going to take 2.125 MW per hour. Lets round up and say 640 MW total. That works out to about 60,000 gallons of diesel if the generator is sized right. At $2.25 a gallon that $135,000 in diesel fuel and a ship to haul that and sit and wait.

Now if you melt and pour 16 hours a day. It’s gonna take 19 days and you’ll need the ships to wait for that long. I have no idea what it cost to charter the ships, but I am guessing that it’s much cheaper given the shipping industry right now. Let’s say $15,000 a day x 19 = total of $285,000 not including hauling it there.

I’m thinking that $700,000 sounds realistic for such a project. You could use an underwater dredger since the seamount is surrounded by the same material you are using as well. That would save you paying one of the ships to wait. But now you’d have to pay 2 or 3 divers for 19 days. You might be able to get everything under $600,000 that way.

It seems like your biggest expense would be ships waiting so maybe if you built 2 furnaces you could cut the cost even more. Perhaps you could buy the ship for the fuel and everything else and then sell it when you were done. The second biggest cost would be power and there is not much you can cut there. Material costs seem to be negligible. Your cost for going bigger would mostly be constrained by power as you could save time by using more furnaces and materials aren’t much of the cost.

Even at $700,000 you are building an island for cheaper than a lot of islands are to buy and this one doesn’t come with a government.

If you went with the pure basalt route your island would be built better than most volcanic islands are and those take centuries to erode in most cases. You could smooth your island out on top while still hot, or form it into a bowl on top and pour soil or sand in it.

I know this is way out there, but it is something to think about. Especially if you start looking at the shallow areas that are just below the water.





Take it maybe a tad more practical? Some Geopolymers need added heat to cure. Find a thick enough mix (one had Basalt fiber added) and combine printing and heating steps?

average price of bentonite between 2007 and 2014. In 2007, the average bentonite price stood at approximately 52 U.S. dollars per ton.

The unit value of diatomite varied widely in 2012, from approximately $100.00 per ton for use as an

sodium carbonate price per ton,US $ 225 - 255 / Ton

One recipe estimates 30% Bentonite Clay/30% Diatomaceous Earth/40% Sodium Carbonate

$156 (3 tons)
$300 (3 tons)
$1020(4 tons)

$1476 for ~10 tons of Geopolymer…

City Sewage and Food Supplies, as a combined topic


Yeah,…lets 3D print a seastead now.


Consider how much more impervious to damage and sinking your design might be, with hundreds of individual buoyancy cells, build into the structure, without the monolithic penalties… Maybe it could even be scaled down to your couple of inches thick, using 2/3 the cement…

(Chad Elwartowski) #9

Could the sand on the bottom be melted to form the island?

If there could be a setup to take sand from the bottom and melt it to form an island you could have a constantly growing island. Definitely use a Fresnel lens to create the heat.

(Chris) #10

The big problem I kept running into with with concrete is that it has to cure some above water and then you have to lower it enough to build the next layer. The time and and weight of structure would make that impractical at sea, but that isn’t to say you couldn’t do that on land and float it out.

I came across those videos you posted while I was researching and they are amazing, I fully believe if it wasn’t for ocean currents, you could print just like that with molten basalt directly into the ocean.

The kid that thought of solar scintering has an amazing future ahead of him.

Yes absolutely. That’s what I was talking about when I said you could replace one of the ships with an underwater dredge. Seamounts are basically undersea volcanoes anyway. So the material around one should be high in basalt. Even if it was all Silica it would still work, but I’m not sure if the erosion resistance would be as good.


As the song lyric goes, “It ain’t necessarily so!” There are cement formulations that will cure, even fully underwater; they typically include a significant amount of Pozzolanic (not sure about that spelling) material (fine, silica-containing materials like fly ash, silica fume, the right kind of volcanic debris.)

The following quote from :

Hydraulic cements (e.g., Portland cement) set and become adhesive due to a chemical reaction between the dry ingredients and water. The chemical reaction results in mineral hydrates that are not very water-soluble and so are quite durable in water and safe from chemical attack. This allows setting in wet condition or underwater and further protects the hardened material from chemical attack. The chemical process for hydraulic cement found by ancient Romans used volcanic ash (activated aluminium silicates[citation needed]) with lime (calcium oxide).

(Chris) #12

How does salt water affect that though? I would think that Chloride penetration in the bonds would be a very bad thing.


So far as I know, the Chloride ion migration doesn’t much effect the cement, though it will play hell with steel rebar. Similarly, though it will cure wet, it won’t cure if the currents wash it away before it can set, so I imagine this would have to be in rather still water, unless externally shielded from being washed away. Not impossible, but much easier in no/very slow currents, IMHO.


Not all geopolymers need added heat. Some will cure at comfortable ambient temps. Add plumbing, baffles and valves, as you progress and control the buoyancy, especially if you’re building a spar-buoy. :wink:

(Matias Volco) #15

Indeed! Very well put. This a post for future reference



What are those “individual buoyancy cells”??

How are they “build into the structures”??

How do they help MY DESIGN? (which has nothing to do with 3D printing) be “more impervious to damage and sinking”?? As if it is now? Or as if you are a critic of my design now?

What fucking “monolithic penalties”?? What the hell are those?

How the hell anybody will 3D print over steel armature and who the fuck will pay $ billions to build that huge 3D printer in order to (DAHHHHH) 3D print a huge seastead to start with??

Guys,…please stop posting while on medication or high on drugs,…


No need to be offensive, abusive, use foul language or slander anyone, in the process of asking a question, that is rather redundant, considering the structure you are discussing does not have, or need any steel armature.

A) It’s a cellular wall structure, so, pockets of air, for enclosed buoyancy, printed into the wall.
B) It’s a truss design, so it should handle stress, including impacts and water pressure against it,
C) By monolithic penalties, I submit solid mass requires more displacement, meaning more
concrete, in this case.
1) reduced quantities of concrete cost less
2) reduced mass for presumably similar physical strength, also reducing that unnecessary
extra volume and extra concrete.
D) I’ve already shown a design for a low-cost, DIY 3-D concrete printer, 2 posts above the wall

E) It’s a common practice to have concrete pumped up to height and across, to reach additional
sections. You can see it in action on most sunny days at large, new construction sites across
the US.

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(.) #18

Intoxication isba variable i the levelnof the language.

(Chris) #20

A Fresnel lense could only scinter it I believe and not get it hot enough to actually melt.


I cuss well enough, but this is a public forum and the guidelines, as well as common courtesy, while not forbidding cuss words, do request that we be respectful of others.