Concrete Submarine - personal Submarine

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Submarine Yacht project
Built a submarine yacht 20 tons in 1996 works well low maintainance cost want to discuss similar projects. See submarine project at www.tolimared.com/submarine
Let me hear your opinion

Old 09-19-2006, 03:57 PM

Guillermo
Ingeniero Naval

Location: Pontevedra, Spain

Interesting project, Wil. But it's going to be no easy task.

Have you compared costs against an all steel one?
Cheers,

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Hello Guillermo

I agree that in yacht building steel is better option. - Not so in a submarine.
Walls of a 9m sub are 18 cm thick and have spheric curves - no way to do this in steel.

While you go for al light hull in a yacht you go for a pressure resistant hull in a sub. This is where advantage of making thick walls with little forming effort becomes important.

second, steel needs maintainance, concrete not. This is why oil rig legs and submarine tunnels are made in concrete not in steel.

Even a small sub like my project is a lot more heavier than a similiar sized surface boat - therefore slipping cost is high - so avoiding go to slip during decades is a mayor cost benefit.

My submarine yacht had lower maintainance cost than similar sized sailing yachts under same mooring conditions. see (www.tolimared.com/submarine)

wellmer

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01-14-2007, 01:05 PM
FranklinRatliff
Rep: 4 Posts: 127

Location: Florida

Quote:
Originally Posted by wellmer View Post
Built a submarine yacht 20 tons in 1996 works well low maintainance cost want to discuss similar projects. See submarine project at www.tolimared.com/submarine
Let me hear your opinion

That's just genius.

FranklinRatliff
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01-14-2007, 03:33 PM
MarkC
Senior Member

Join Date: Oct 2003
Rep: 13 Posts: 155
Location: Germany
Visit www.psubs.org - the web/blog site for self-built submersibles. They have books, articles, plans for sale, photos, reader's projects etc. Everything.

MarkC

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marshmat's
Senior Member
Join Date: Apr 2005
Rep: 81 Posts: 1,802
Location: Ontario
Very clever little thing, Wilfried. I'm quite impressed.
Curious what you're doing for air supply while submerged, and how you're dealing with carbon dioxide buildup- does it have a lithium hydroxide scrubber, compressed air tanks, etc- or do you just surface when you need to change the air?

-Matt-

In a 20 ton submarine you have about 20.000 liters of air, you take about 2 liters per breath, and you can rebreath the same air several times until CO2 build up becomes critical - this gives you hours of divetime without air treatment in a submarine yacht.

wellmer

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longliner45
Senior Member

Rep: 43 Posts: 711
Location: Ohio
is this hull reenforced with steel rebarb? or anything else?,

longliner45

Hello Longliner45,

There is no need for experimental concrete in a submarine hull as the forces that appear in a submaine hull of thick walls are the same as in the walls of a submarine tunnel, the legs of a oilrig or the base of a concrete dam.

So reinforcing the concrete with something else than steel would not make any sense.

The reason why you use steelreinforcement in concrete is to give the concrete strenght against tension forces.

Steel and concrete have a very similar extension characteristic when temperature changes - this makes them ideal partners in a composite material.

Do not use other reinforcement materials in your concrete it is asking for problems...

Concrete engineering is a very simple sience with a couple of quite basic rules and very forseeable results if you stay within the rules.

This is why millions of constructions all over the world trust in reenforced concrete in aplications where live depends on it.

The new thing in a concrete submarine is applying the proven engineering of tunnels, oil rigs and dams, to submarines - basicly adding a motor, rudder, and tanks, to the structure to convert it into a submarine.

Do not leave the proven field of normal concrete - this is a dangerous way that can bring up catastrophic unexpected failure.

Kindest Regards,
W.Ellmer

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marshmat

Location: Ontario
Spoken like a true civil engineer.... they sure love their concrete.... you wouldn't happen to be one, by some chance?
Some of the researchers here are investigating the use of carbon reinforcements in/around concrete columns... frankly I don't get the point; concrete is popular mainly because it's dirt cheap, and carbon tends to be insanely expensive... but I guess they can justify it somehow. Also some work there on fibreglass-mesh reinforcements that might be promising.
It looks like you've stayed with tradition and overbuilt everything- a sound design philosophy for this project, IMHO. Very cool, indeed.

-Matt-

Hello Matt,
I am not a civil engineer, but i have discussed this a lot with civil engineers, and the concrete handbook for civil engineers is my bible in this as i really want to build with a material that is investigated and forseeable when my life depends on it.
Fiber of any kind in concrete is big problem: The key factor for strong concrete is compacting the concrete during casting. So spaces smaller than 3 cm are TABU en concrete construction this is why you see workers with vibrators compacting concrete between the steelbars on every construction site - how would you fill and compact concrete between the micrometer spaces of a glass or carbon fibers - i have never seen such an application in any construction site - probably there are good reasons NOT to do it.
Anyhow there are fiber concrete aplications for roofs like ETERNIT. But those are aplication where the concrete is not supposed to take forces of any kind.

Wilfried

--------------------------------

Concrete Submarine Yacht

MarkC
Visit www.psubs.org - the web/blog site for self-built submersibles. They have books, articles, plans for sale, photos, reader's projects etc. Everything.
Hi I have published some photos of my submarine www.tolimared.com/submarine in psubs.org moki files - There is also a discussion about concrete submarine yachts on this forum from a year ago...

Regards,
Wilfried

Concrete submarine yacht - hull without ballast and tower
(image)

Concrete submarine yacht - hull with ballast machinery and tower
(image)

Concrete submarine yacht - inside nice and dry no filtering no condensation
(image)

wellmer

Guillermo
Interesting project, Wil. But it's going to be no easy task.
Have you compared costs against an all steel one?
Cheers,

Hello Guillermo,

I already built the concrete submarine yacht, dived and tested it for a decade, - it was quite easy. See [www.tolimared.com/submarine] for photos. There are also photos published in boatdesign.net - gallery.

Most complicated part is the concrete forming for a blimp shape, but i came up with a tecnique that allowed casting with a moving forming process similar to the one used in Torontos TV tower.

What concerns cost against steel only the sandblasting of a steel hull would be more expensive than the complete concrete submarine hull.

Regards,
W.Ellmer

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RatliffFranklin

Location: Florida

Although perhaps at some sacrifice to internal volume, could not the construction process be simplified by going to a cylindrical shape?

RatliffFranklin

Hello Franklin,

Of course you could also make a cylinder shape, maybe forming is a little easier - not much if you have a proper technique.

Anyhow the fine thing of a blimp shape is that you get a deep belly where you can store your sand ballast on a very deep point this gives your submarine a high stability in static dives. So it will not stand up like a bottle if you move from front seat to engine room during dive.

You also get 2m standing height - this is something important for comfort in your submarine on longer turns.

A cylinder of 2,4m diameter with end cups would be a hull very hard to move around.

The blimp shape gives you performance and range like a normal motor yacht.

Kindest Regards
Wilfried

longliner45

Location: Ohio
welmer I agree with you there,I believe Thomas Edison added bamboo to concrete to beef it up ,,first,also have you ever tried to sqeeze a raw egg,to burst it ? please keep us posted ,,very interesting project,think of all the salvage in shallow water!good luck,,,, longliner

joe_cope

Location: Shanghai, China
What kind of concrete did you use? If I'm not mistaken ordinary cement is slightly porous and would allow water to seep in (and air to seep out) so you'd want to use a waterproof cement, right? Also, regular cement shrinks when it cures, right? so did you have any issues with shrinkage or cracking in the hull during the curing process?

Quote:
...have you ever tried to sqeeze a raw egg,to burst it ?
I've done that. I've crushed a raw egg by squeezing it along it's short axis, but not the long axis. Still took a hard squeeze though.

What about using some kind of fiber-reinforced plastic to increase flexability, reduce the chance of cracks, and to reduce weight? I'm remembering some kid's toys back in my hometown that were made out of recycled milk jugs. You could use some kind of plastic and glass or carbon fiber and build it up in layers (paint it on layer by layer)...
Reply With Quote
joe_cope

concrete submarine hull watertight

The idea that concrete is a kind of sponge where water and air passes trough is not realistic - concrete made correctly does not allow pass of water at all. You see many structures without any coating that resist water under pressure. without any additional measures. (tunnels, dams, bridge fundamentations) - anyhow if you are concerned about this have a coating on your submarine - i recommend a tarmac based one as i had on my testproject [www.tolimared.com/submarine] i also was rather neurotic about what would happen when the coating would be compromised - until i noticed that the coating had been compromised in an area of 10x10 cm and i had not noticed it - no wet spot inside no filtering under pressure - just nothing. Today after having seen this in practice i would say coating is fine for estetical reasons - not necessary for tecnical ones. - If you have a imagine of a concrete submarine hull as a wet, filtering place just look at the poto in the photogallery - the hull was not only without any filtering it also was without condensation - the bilge stayed nice and dry under hot sun, and under ice cover - thing i had not expected in first place.

wellmer

concrete submarine yacht, make it flexible, shrinking, cracks

What kind of concrete did you use? If I'm not mistaken ordinary cement is slightly porous and would allow water to seep in (and air to seep out) so you'd want to use a waterproof cement, right? Also, regular cement shrinks when it cures, right? so did you have any issues with shrinkage or cracking in the hull during the curing process?

I've done that. I've crushed a raw egg by squeezing it along it's short axis, but not the long axis. Still took a hard squeeze though.

from wellmer

The point is - any intent of making concrete "better" is dangerous as you go away from what is proven state of art of concrete construction.

There is also no need to make it "better" as normal concrete has all properties required for a submarine hull.

I do not recommend any additives on contrary this is a way to make things more complicated to handle and increase the probability of failure. Concrete bible says that you should only use that kind of things if you have a concrete lab available - if you have no lab - stay at normal cement - in normal conditions - it is the only way to get a good result with predictable strenght.

The egg shell is a good experiment - especially if you compare it with a beer can - if you bring both to depth you will find that egg is better for diving. This is because it maintains form until it breaks.

Adding flexibility does no good as concrete has a reasonable flexibility anyhow
and changing form under pressure (flexible) is a problem - not a advantage.

In a submarine you want a solid pressure resistant wall no layers at all - layers mean changes in force flow that are impossible to calculate and predict.

Cracks are part of concrete construcction as rust is part of steel construction. Other than in glass a crack in concrete does not weaken the ability of the material to take forces - basicly for compression forces it does not matter and tension forces are not taken by the concrete - they are taken by the steelbars.

wellmer

joe_cope

Location: Shanghai, China
Quote:
Originally Posted by wellmer
Cracks are part of concrete construcction as rust is part of steel construction. Other than in glass a crack in concrete does not weaken the ability of the material to take forces - basicly for compression forces it does not matter and tension forces are not taken by the concrete - they are taken by the steelbars.
How do the cracks in the concrete affect the watertight integrity of the hull under pressure?

And what about shrinkage? I know that there is "non-shrink" grout for things like swimming pools. Would shrinkage while curing be a problem for larger subs or thicker hulls?

joe_cope

concrete submarine hull shrinking cracks
Hello Joe,

The kind of cracks you get in concrete by shrinking under normal conditions do not go trough the structure and are very small. The problem engineers worry most about is that water can reach the steelbars and produce rusting and therefore weakening on long term - therefore there is a normative that says that you should maintain a concrete cover of at least 2cm over the bars to enable them to take the full force and to avoid filtering water down to the bars. So stay within that normative and back it up with an aditional bitumen cover of 1mm - you will be at the save side and have no problems with your concrete submarine hull - no filtering.

In worst case you have a filtering it tends to stop under pressure as spaces reduce under compression. Trieste had a 11.000 m dive with a filtering on surface

Again i know the idea of cracks is a little scaring especialy if you have submarine films in mind where glass and acylic cracks just before failure.

You will get piece of mind if you talk with a construction engineer about this - and his state of mind when cracks appear in the colums of a building that take thousands of tons of force ...

They do not worry about cracks that appear during curing of concrete the only kind of cracks they worry about is the kind that appears years after the construction and bring up colors of rusting bars and other sign of problems and filtering in concrete due to bad execution of basic concrete rules.

Shrinkage is no big issue in normal construcction. If you have walls of dozends of meters as in dam construction you get a problem because concrete produces heat while curing and must not reach more than 30degrees Celsius during cure process.

Again, stick to the proven you will get a good result - no reason to see ghosts of cracks, shrinking, filtering everywhere - If you ever have seen a concrete hull in parctice you will trust it as you trust bridges, tunnels, and colums in everyday life.

You ever thought about the fact that the building above you is hold in its place only by a concrete column full of cracks due to curing process - a scaring idea - similar scaring as the idea of a watercolumn of hundreds of meters above your submarine.

This is the same thing as first glassfiber hulls came up - people said: oh you would cross the ocean in a fragile boat of glass? or even worse in one made out of coal? - if you ever have seen and touched a real hull and get a idea of its real strengh - all those ghosts simply disappear.

Kindest Regards,
W.Ellmer

kach22i's
Architect

Location: Michigan
While everyone seems to of focused on the material, I'd like to say something about the form.

1. It should have a flat top or deck so that one could choose the fresh air and sunshine.

2. It should be shinny and pretty with a good deal of thought gone into it's Industrial design.

Other wild options may include special themes or novelty.

http://www.buckeyestateblog.com/node/1802

http://www.otwdesigns.com/Type7/type7.htm

I don't mean to mock your industrious ideas, just looking at it from a different vantage point - it's gotta sell.

Maybe add a sail?

kach22i

Hello kach22i,
I apreciate your contribution - finally - a yacht must sell. I also thought a lot about a kind of deck - in first place to have a place for a fine anchor solution with winch and chain storage. - in second place to have cells for blowing them out with air in emergency. This is not so important for a small sub like my submarine yacht [www.tolimared.com/submarine]

But very important for a bigger ship where an anchor winch is a must and drop weights are not a viable security solution. - Also deckspace would be big enough to give it a real use.

Kindest Regards,
W.Ellmer

kach22i

Now you are talking, room for a bikini boat party............why else own a yacht?

EDIT: Found This..................................big deck.

http://www.sub-find.com/deepstar.htm

http://www.submarine.co.mp/

http://www.balicruises.com/sea/submarine/index.html

I see nothing wrong with other themes, just posting samples.
http://www.ossapowerlite.com/custome...s/nautilus.htm

Quote:
Nautilus is Exomos' version of the submarine in Jules Verne's 20,000 leagues and is intended to be used by tourist resorts to give visitors a unique view of the local marine environment. It seats seven, with the option to add 2 jump seats. The anticipated final weight in water is eight tons, 15.5 meters long, 2.5 meters in diameter. Nautilus is Powered by our OSSA Powerlite a 500vdc version of our OSSA Powerlite 35hp motor. The motor turns a 26" x 13" pitch, 5-bladed propeller. Power is provided by a state-of-the-art 512v lithium-ion battery pack which is recharged at dockside.
http://www.vulcaniasubmarine.com/TES...%20MINISUB.htm

http://gohawaii.about.com/library/ga...gallery428.htm
Reply With Quote
kach22i

Hello kach22i,

The submarines you show in the pictures are all variations of one segment the tourist submarine.

Those boats are built to load a big quantity of tourists in on a protected pier and bring them out maybe half a mile to a protected divesite in a 30 minute dive.

Once in nobody is allowed to leave seat until dive ends.

They look like a submarine tourist bus - because they are constructed to be one.

They are not yachts in the sense of yachting going for a longer trip, live aboard, etc...

Acrylic viewports of that size take a maximum of 10000 dive cycles and then have to be replaced at prohibitive cost.

A tourist sub similar as an airplane has to be certifiacted for passenger transport. So this is a segment completly apart from yachting.

In a private yacht you can do and use what you consider - in public transport not.

You will never get a certification for a concrete hull as there are no normative rules for certification.

So the sector of tourist sub will be the LAST segment where you will see a concrete submarine. - This is why my design was NOT meant for it.

The design was made to perform as low cost low maintainance yacht being parked on a mooring in a field of sailing and motor yachts, and perform for weekend trips in a yachtintg environment.

I found out that my submarine yacht had even lower maintainance cost than the sourrounding sailing and motor yachts so given the restrictions to tourist submarines i believe that this is the segment where concrete submarines might have a future.

Kindest Regards,
W.Ellmer

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joe_cope
Location: Shanghai, China
The more I think about your little submarine (I think if it as a "cementosphere", even though it's an ellipsoid. It makes me think of the orginal Bathisphere) the more I like it.

What would be really cool though, would be if it could be transparent. The walls of your sub are 18cm thick, right? Would it be possible to build an equivelant hull out of something transparent, like a plastic, glass, or pyrex? I imagine that 18cm of pyrex would hold a lot of pressure, particularly if there was some kind of reinforcement running through it (I'm picturing those windows that you see in American high schools with the 2cm grid of fibers inbedded in them so they don't get broken).

Quote:
Originally Posted by wellmer
Even a small sub like my project is a lot more heavier than a similiar sized surface boat - therefore slipping cost is high - so avoiding go to slip during decades is a mayor cost benefit.
What is "slipping cost"?

joe_cope

Hello Joe,
concrete as hull material and a series of spheres in a 2 hull concept might be a way how a independent submarine (no mothership) could reach a depth that comes close to average ocean depth. I discussed this matter with Carsten in Germany (the Guy who builds the merlin sub) a couple of months agro.

Now what concerns trieste, the first intent for deep diving was a steel sphere on a steel cable (bebe) which is dangerous as the steel sphere is heavier than water and sinks if cable breaks. So Piccard added a big gasoline tank on top to the concept that gives the sphere additional float to get rid of the cable.

Triestes steel sphere passenger compartment had 2m diameter and was made in Germany by Krupp in the same installations where the monstercanons bertha and dora where built - it is (still) the biggest installation for the biggest single pieces of steel in the world. They formed it by hammering a 2m red hot steel block and then machining it down to final half sphere shape - glueing 2 half spheres and a central ring together. - imagine the cost -

You can form a 2m concrete shpere in your garage with any wallthickness - no Krupp with mega installations needed. That is a BIG difference in cost. You also can form a 5m sphere - not even Krupp can do this in steel.

It is clear that massive steel has a higher pressure resistance than concrete.
So a concrete sphere will not go down to 11.000m like trieste did but you may go well below thousand meters and can possibly reach ocean floor outside submarine cañons.

I am not very optimistic of forming something similar out of acrylic as this is a difficult material with 10% shrinking - heat processing after each machining step etc... have never seen piezes of glass except a few millimeter thick nor in pyrex.... Honestly the only construction material i know where massive pieces of 20 cm thickness and far more are formed sucessfully evry single day all over the world is concrete.

The idea of glass with wire grid for submarines is a thing i would not recommend...
To get a good idea what submarine viewports should be made of and what is state of the arte read (Jerry D. Stachiw) and (http://www.psubs.org/).

What i want to say with "slipping cost" is: Depending on the material of which your yacht is made you have to pay whenever it must be taken out of water for painting, repair, check. In a wooden yacht this is a big MAYOR cost as you take it out at least once a year paying for crane, for using shipyard installation ect...

A concrete submarine hull is supposed to stay unaltered in water similar like a tunnel or a bridge fundamentation - for decades - centuries... this is a big cost benefit compared to other materials...

Just put a bouy and let it hang there as i did summer, winter, year after year - scrap the algea is all you need do - see:
(image)

Kindest Regards,
W Ellmer

kach22i
Architect

Location: Michigan
Quote:

...So the sector of tourist sub will be the LAST segment where you will see a concrete submarine. - This is why my design was NOT meant for it.
You are right of course; I was just admiring the decks of the underwater buses and ability to look out.

I see that your design has it's own beauty and it also has side view ports which will help it sell.

I'm not sure how much drag a deck will have, nor how having a flat surface so near a potentially turbulent surface will affect handling and sea keeping.

Any observations I may have are distant ones and somewhat removed from engineering.

kach22i

To get a good idea what submarine viewports should be made of and what is state of the arte read (Jerry D. Stachiw) and (http://www.psubs.org/index.html.
w.ellmer

joe_cope

Location: Shanghai, China

What a shame... floating around the keys or Hawaiian islands in a clear bubble really sounded nice.

joe_cope

submarine yacht deck, viewports
Hello kach22i,

A deck is a fine thing on a big submarine so you can sit on deck have table and chairs on deck in harbour - maybe a party.

On my 9m submarine a deck would be a surface of 2x1m before and aft of the tower - just enough to stand on - nothing for a real use - and a additional surface you have to scrap birdshit off when boat is hanging on its bouy.

You can´t use any deck in any submarine in open ocean as waves will wash over it - this is why submarines have a tower. If you want a deck usable in open water you need a lot of freebord and this is a lot of additional drag. See (ussubmarines.com) - in fact you need to extend the tower to the whole sub.
Anyhow if you plan a lot of activity on deck and are willing to accept drag it can be a solution.

What speaks against the concept of enourmous curved acrylc surfaces like in a tourist sub is cost. Viewports only can take 10.000 dive cycles then must be replaced. It is ok if you have a tourist sub you earn money with each dive. If you dive 10 times a day you have to rebuild whole ship after 3 years. This may work for a tourist bus application - a 3 years livetime is prohibitive for a yacht.

This must be why ussubmarines 65m megayacht submarine has not yet been realized - tremendously expensive and rebuild all acrylic surfaces - after 3 years...this is too much.

In my concept (www.tolimared.com/submarine) you have 4 viewports of 50 cm diameter. Those are disc shapes which take more loadcycles than domes.
You also can change them at reasonable cost - even without taking the submarine out of water.

This gives you enough light inside see:

You also have a fine view of underwaterworld if you bring your face close all your angle of view is covered by the viewport.

So limiting the number of viewports and stay with flat disc shape instead of dome is a key factor for a reasonable life span and a reasonable cost in a submarine yacht.

Kindest Regards,
W Ellmer

What a shame... floating around the keys or Hawaiian islands in a clear bubble really sounded nice...

You can get half spheres of acrylic up to 6 foot diameter - this is bringing acrylic domes to the limit - Deep Rover from phil nyutten - is such a submarine concept floating around in a bubble - unfortunatly needs a big mothership - and replace your bubble after 10.000 dive cycles ...

Kindest Regards
W Ellmer
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Thijs Struijs [psubs.org] 11 Feb 2007

concrete submarine yacht

Hello Wilfried,

That's a great sub you built. What's the status of it now? (Did you sell it?
Is it still in Austria or did you ship it to Colombia?)
Before asking you questions i suppose i should read your bible to acquire
some basic knowledge. But there are a view questions i would like to ask you
right now.

1) Is the hull made in one piece or did you glue two cones together?
2) How did you make the mold? I suppose you used an internal (male) and an
external (female) mold. How do you prevent the internal mold from floating
in the wet concrete? Could you remove the internal mold after the concrete
had cured and schrunk. Maybe you have some pictures of the building proces.
3) I suppose the viewports are seated in steel rings? Applying steel inserts
in concrete constructions are probably common practis. I had better start
reading right now.

Greatings,
Thijs Struijs
The Netherlands
-------------------------------------------

concrete submarine yacht, status, forming, viewports

Hello Thijs

...well what happened with my concrete submarine - here is the strory...

Lake Atter is a alpine Lake with little access by road. There was only one site (you see it on the picturs)(http://tolimared.com/submarine) where the road comes so close to the water that you can place a crane there and lift a heavy submarine into the lake like on a pier.

Unfortunatly a few years after i had my submarine in the water this place was converted in a bathing area with a sand beach. So there was no site for a heavy construction crane any longer. The cranes of the yacht clubs have 5 tons limit. So my sub was trapped in the lake.

A buoy on lake Atter for yachting purpose costs 50 Euro a Month. As i got a job promotion i lived in Vienna which is some 4hours in car from the lake. Of course i still came for the weekends, took my generator and portable battery pack out of the car - packed it in the red plastic boat you see in the pictures - rowed out the 50m to my submarine´s bouy packed the batteries and generator into the sub - let the plastic boat on the bouy - ready to dive.
Great fun.

My wife a german language student from colombia got a kid - i got a job offer for southamerica a second kid on the way - you can not fly after 3 month of pregnancy so we had to take off and leave the submarine on its bouy i still paid the bouy fee from southamerica.
For 5 years.

Obviously the fact that a miserious submarine is anchored in their lake drove some locals completly nuts they wanted to have a look in and broke the lock of the top hatch with a hammer - unfortunatly damaging the seal in the process.

My brother from austria reported me the fact - but there was little i could do from colombia. With ballast on board the submarine has only some 200 liter of flotation so if rain and spray water enters trough the hatch for months- sooner or later it would go down i was aware of that. Anyhow i could not use nor sell the submarine from southamerica and the buoy check came every month. So i decided to make an attraction for local divers and let things go their way .

A couple of months later my brother reported me from austria that my sub went down and has converted into a attraction for the divers some 30m down - the mistery submarine from lake Atter...a honorable place for a concept study. This solution also offers the possibility of a long term study how hull and viewports develop during the next decades. Reportedly both are in great shape.

Being installed in Colombia (South America) of course i checked the possibility of a site with unlimited access to the ocean for building a submarine yacht of about 15 m lenght that would be capeable of doing ocean crossings without a support ship and give enough space for live aboard. I found a nice piece of caribbean shorline near TOLU where economic labour force and road access is available.

My favorite plan is to get a buyer or investment partner and build the hull in TOLU near cartagena then take it to a place wherever in the world the buyer needs it for final equipment. I would document building status by digital Photos from colombia.

At the moment i make a living as an import export advisor (http://latinindustry.biz) but if a investor or buyer should show up for a submarine proyect i would move inmediatly to the building site and start building the hull.

Concrete forming molds
-----------------------
What concerns concrete forming you should have a look at the forming process with "slip forms" as done in toronto TV tower - this consists in a small ring forming area that moves up the building a step evry 5 days - just do it horizontally. You need to compact the concrete in the mold - if you build whole mold at once you can not access all areas. If you check how oil platform legs, bridge foundations, cooling towers, etc... are formed you get a good idea how to do it - they do not use a complete mold they form in small parts...of course all mold parts get removed and must be prevented from moving during pouring in the concrete. My mold material consisted in 5m2 cheap pressed sheet material and 50 kilo pinewood.

Viewport seatings in a concrete submarine
-----------------------------------------
The general purpose of viewports seatings is that you need the area of the viewport being stable and flat. In a submarine with a thin steel skin over a rib skeleton the skin moves under water pressure at dive. The viewport seat stops that movement in the area where acrylics and hull meet. In a concrete submarine you will not have that kind of movements.
A massive steel peace in your hull will interrupt uniformity of force flow. So i opted for forming the viewport seating from concrete - no steel ring. Worked fine at my pressure test model, worked fine at my submarine.

Kindest Regards,
Wilfried

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Brian Cox 11 Feb 2007 [PSUBS-MAILIST]

concrete submarine yacht

Great to hear from you again ! I think your sub is the greatest ! I want to build one ! I better finish my current one first though. Thanks for updating your web site and keeping us informed.

Brian Cox, Ventura, California

--------------------------------------------
Hello Brian let me know how i can assist... i could build you a hull...

Kindest Regards,
Wilfried

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Øystein Skarholm / psubs.org / 11 Feb 2007

concrete submarine yacht - want to build one -

How long time will it take you to build a hull 10 meters long 2,5
meter Dia with 200mm thick walls?

--------------------------------------------
Hello Øystein,

concrete submarine yacht - building time

I can have a hull ready in less than 3 months and ship it wherever you want...

Wilfried
--------------------------------------------

Carsten Standfuss - MerlinSub 11 Feb 2007 / psubs.org

concrete submarine yacht, lift it

Hi Wilfried - its still yours, even as wreck - you are the owner.
How long is it now at dive station ?

So somebody from Austria or somewere in Europe can purchase it from you, raise it, clean it.. He can make an new interior and maybe with bigger ballast an trimtanks.. and use it.

regards Carsten
--------------------------------------------
Hello Carsten,
It is down now for 5 years - the hull is still in great shape - and will be for decades to come - anyhow it is cheaper to build a new one than to lift it - i am quite happy having it there as a diver legend...

Kindest Regards
Wilfried
--------------------------------------------

Hank Pronk [boatbuilding]

Hello,
my name is Hank Pronk, I am a fellow sub builder. I am planning to
build a 10 m sub for cruising. I just came across your concrete sub
site and I am very interested in what you have done. i have concidered concrete in
the past, but inside a permanent steel form. I love what you have done and
am very interested in your forming metheod. I would love to hear from you
and get some ideas. Thank you and I look forward to hearing from you.
ps,, my sub is on psubs picture gallery under Hank Pronk

---------------
Hello Hank,
Thanks for your e-mail i am glad to help wherever i can. I first thought of a
outer steel hull too - until i noticed that there is no marine conrete
structure using that concept.

See:
http://imulead.com/tolimared/submarine

especially the picture:
http://imulead.com/tolimared/submarine/concrete.jpg

Non of those projects uses permanent steel form - my advise is always - do
not
reinvent the weel - take what is proven.
My forming method is ring forming in a moving mold - see those projects and
you
will get an idea how to tackle the matter - it is tricky in detail if you
choose
a complicated shape like a blimp shape but can be managed. Make sure that
concrete can be compacted in your form properly - make also sure that you
can reuse the form in the next ring segment.

Kindest Regards
Wilfried

--------------
Hello, thank you for your fast reply. I was under the impression you poured
the entire hull in one contiuouse pour. Its funny as I am typing this ,,it
just hit me how you did it. You poured a full length section then rotated
your mold and thats why your hull is the same shape all the way around. How
many pours did you require. Yor site says the hull thickness is up to 18 cm
thick. When I apply that to my sub design it is far to heavy to float. Can
you tell me more about the hull thickness. Also how have you allowed for
window seating, is there a steel ring cast into the concrete? Do you have
any external anchor points for anything that you may want to bolt to the
hull. Thank you again for taking the time to explain things.
Hank Pronk
-------------
Hello Hank,
A rotating full length segment can work - i would be concerned about the forces
during building when you have half a hull...
So i did ring segments of 30cm height.
Hull thickness is 18 cm where hull diameter is 2,4m and only 5cm at the ends.
What you need is that the ratio hull diameter/wallthickness is the same in any
part of the submarine to keep compression stress the same over the complete hull.
I would suggest to avoid anything that interupts force flows in the hull so i
opted against steel seatings and made the window seats from concrete too. For
anchoring things you can use the same tecniques as you would anchor in any
concrete wall - drill in put a steel anchor with fixation cement.

Kindest Regards,
W Ellmer

--------------
Hank Pronk

Hello again, thank you again, If I understand you,,,,you started at one end with a ring and moved toward the other end in 30 cm segments. If that were the case the ring segments would have to shange in size. I am confused haha. Do you have any through hull fittings propellor shaft or electrical.
Thank you
Hank Pronk
ps my design is coming together very well

-------------
Hello Hank,
Start with the center ring segment and build to the ends.
Kindest Regards,
W Ellmer
---------

---------------------------------------
BillyDoc [boatbuilding forum]

More on concrete structures

Hi Wellmer,

I loved your sub! And I really like the idea of using concrete for the hull. Concrete being extremely strong in compression, which is what the hull experiences if the inside pressure is maintained at normal atmospheric. Is that what you did?

Anyway, on the subject of concrete, my Father did some extensive research on this wonderful material with the end of determining how to make it the strongest possible, and he learned some interesting things about this stuff in the process. Ultimately, he was able to produce concrete samples that seemed more like a very dense ceramic than normal concrete, and were extremely strong and tough. Much stronger than anything commercially available to this day. The process he used to do this was difficult to achieve, however.

Let me explain, in case this might prove useful to you.

First it is necessary to understand that concrete is comprised of many very small particles made anhydrous in an oven. When water is added these particles combine with the water chemically and produce crystalline “spikes” which grow from the surface of the particle. When particles are tightly packed these “spikes” mechanically interlock, and this is what gives the concrete it's strength. Obviously too much water will float the particles apart and weaken the resulting product. This is why different concretes with different compression ratings are available, the difference is the amount of water used in mixing (for the most part, there are other tricks that can be used as well). More water makes the mixing easer, but the result is weaker.

Considering this, my Father reasoned that the strongest concrete would result if the particles could be packed together so tightly that all particles were physically locked against each other before any water was introduced, and this was the object of the procedure he developed, which went as follows.

The dry concrete mix was put into a mold with an elastomeric surface somewhere that could be compacted against the concrete. The concrete mix (sometimes including fibers such as can be made from polypropylene for added tensile strength) was packed into the mold as tightly as possible and the mold sealed up. A vacuum was pulled on the contents of the mold to remove as much of the trapped air as possible. Atmospheric pressure would then pack the concrete into the mold via the elastomeric surface until it felt hard to the touch even before curing.

But let me digress a bit about this vacuum business. Evacuating a container with a bunch of tiny particles in it takes a very long time. This is because when gases normally flow through a hose or whatever, the individual molecules are bouncing off of one another and generally pushing each other along. If a vacuum is applied to a bunch of concrete powder, however, the mean distance between air molecules very quickly gets longer than the mean distance between particle surfaces . . . and individual molecules can no longer bang into each other and push things along. At that point they merely bounce around from surface to surface until they finally bounce out a hole and don't bounce back. If you want to evacuate an area of, say, one liter, this can take a couple of days of applied vacuum. The moral of this digression is that for practical purposes you need a good system for “distributing your vacuum” when making larger structures.

But to get back to the process, once the concrete is evacuated and compacted by atmospheric pressure the whole mold can be immersed in water and a few leaks introduced. When I have done this with transparent molding materials I have seen a wave of water slowly travel through the material until there were no discernible bubbles left. And, once water has been allowed to flow between the individual particles, there is no remaining pressure that would tend to separate them. They remain exactly as they were, compacted in the extreme.

At that point the normal “curing” process begins, and after a day or two the resulting material is incredibly strong.

Sorry to be so long-winded, but I suspect that this process could be applied to your submarine building. Anyway, I thought you would at least find it interesting. I used a similar process to produce very strong fiber composite materials several years ago (http://poiesisresearch.com/Pdfs/5,248,467.pdf). The trick there was the realization that the fibers could be packed into densities nearing 90% fiber if they were so packed before any resin was introduced. A piece of carbon-fiber/epoxy with 80 to 90% fiber density is fairly strong.

BillyDoc
--------------------------

marshmat

Location: Ontario

Very interesting concept, BillyDoc. Sounds almost like the concrete engineer's equivalent to the vacuum infusion process used in fibreglass and carbon work. It'd be interesting to see it developed further.
Concrete really is an amazing material- cheap, strong and incredibly versatile. Seems a remarkably good choice for the submarine.

-Matt-

---------------------------

Poida
Location: Australia
Billy Doc - Was any vibration introduced to the mold as the air was being evacuated?

---------------------------
BillyDoc ...more like a very dense ceramic than normal concrete... whow!!! This might be open a complete new horizon.

In my submarine yacht project - http://tolimared.com/submarine - i used normal concrete. This boat is designed to go some 300m down with a safety factor of 1/3 so might have a destruction depth of 900m - anyhow the weak point is not the hull made of normal concrete but the viewports. I discussed with carsten from euronaut that it would be a fine thing to get rid of viewports and replace them by camera system on a deep diving boat.

Deep diving is always the question HOW deep diving - i would estimate that a concrete sub with a hull still able to float (keep foam and gasoline flotation bodies away) could go to maybe 2000m.

Your special concrete could give us still floating spheres that could be able to reach ocean bottom at 97% of the planet.

Currently submarines that can reach average ocean bottom depths have spheres of steel, titanium, glass, of about 2m maximum diameter as passenger compartments - this is the limit of material handling - you can not build a 7m diamater sphere with 1m wall thickness in those materials -

BUT you could with your special concrete!

The limited comfort in a 2m sphere limits divetime to a view hours and depends on a mothership for deployment.

Your method could open the possibility of big autonomous submarines reaching ocean bottom - maybe a small step in concrete construction - a big step in ocean exploration...

Kindest Regards,
Wilfried Ellmer
---------------------------
BillyDoc

Marshmat,

You are quite right, the technique described above is similar to the vacuum infusion techniques used for fiberglass, etc . . . but with one very important difference. In those techniques a vacuum is used to “assist” the flow of resin through the material and is applied at the same time or shortly before resin infusion. The problem is that even though a very low vacuum may be applied externally, if the fibers are packed very densely the gases will not be entirely removed (and sometimes not even close) and air bubbles will accumulate in various odd places as the flow front traps and compacts these remaining gases. To avoid this problem extreme care has to be used to design the part and mold such that all gases are swept ahead of the flow front during infusion. Unfortunately, this is extremely difficult to do in practice, and a screw-up here can ruin the entire part. With the process I described above the gases are removed to an acceptable level before infusion (taking the time to do so), so the flow front geometry simply doesn't matter. It is truly mind-boggling how long it can take to really de-gas a tightly packed “geometry” like fiber or concrete particles.

Poida,

When I was experimenting with this technique I didn't use vibration at all, just an elastomeric “window” for compaction via atmospheric pressure. I wish I had thought of it, as it is a very good and obvious idea!

And the undesirable effect of using an elastomer is that unless the elastomeric material used is very flaccid, when the water is infused it will try to “rebound” thus making the internal space larger than it should be, thus also reducing the compaction. Another problem is that when the concrete is even slightly compacted it is quite rigid, thus making it difficult to “shape” in the mold. All of which has got me thinking . . .

If I were to construct a submarine hull, I would take this approach:

First I would construct an inner hull of metal, say aluminum, with a modest metal thickness. Around this inner hull, and at a spacing sufficient for the concrete hull, I would weld up a second metal hull. Since I have unlimited funds to use in my dreams I would make this outer metal hull out of Nickel/copper alloy and avoid some future bottom scraping. Both hulls only have to be strong enough to maintain their shape with the weight of concrete between them.

Assuming an oblong spheroid sort of shape, I would tilt the thing up so the long axis was vertical, and make an arrangement for a hopper to hold sufficient concrete for the hull, and a vacuum connection.

Then I would put the whole structure inside a large separate vacuum chamber, pull a vacuum on the entire works for a day or two, and while the vacuum was still being pulled (especially below the hopper outlet) open the hopper and allow the cement to drizzle down into the space between the metal hulls. Doing it this way should de-gas the stuff nicely! And while pouring in the cement, I would be vibrating the entire setup as much as possible as you suggest! I think that this would compact the material quite completely as there would be essentially no gases to hold the individual particles apart.

After the concrete was in place I would introduce water into the hopper, the inner hull, AND the vacuum chamber simultaneously so that it can infuse the concrete. I would do it this way to avoid a differential pressure on either the inner or outer metal hulls as much as possible since this could distort them. The inner hull could also have a matrix of very small holes over it's surface to allow the water to infuse through.

I think that when the concrete curred this would produce a very strong submarine hull with a convenient metal sheath! I haven't looked at thermal expansion for this approach, but there is always steel if this proves to be a problem.

Wellmer,

Unfortunately, this is not such an easy process to accomplish in the average home garage. On the other hand, if there was enough demand for such hulls the tooling required is where the money would go, for the vacuum chamber and pumps primarily, as the concrete and material for the inner and outer metal hulls would be fairly cheap. Does this sort of an approach sound like anything that would be economically feasible to you? Can you imagine applying such a technique to your designs?

BillyDoc

--------------------------

Hello BillyDoc - i am well aware that your special concrete is not a process i would recommend for the guy that builds his personal submarine in a garage.

In a submarine yacht a depth of 300m (900feet) is enough - and you can do that with normal concrete which you can form in a garage under ACME conditions - Coral reefs and most of continent shelf is in reach.

The interest for superstrong concrete might come from submarines for deep diving that are going for things that are down in the abyss at 2000m and below. Could be scientific purpose, could be salvatage ... my design was oriented to yachting (http://tolimared.com/submarine) with big viewports and daylight in the submarine - not to deep diving -

Deep diving always means sphere hull shape for the pressure vessel - you could combine a seagoing streamline normal concrete outer hull with a series of superstrong spheres as inner pressure vessel. The problem is how to build such spheres - current metal and glass tecnology permits a maximum of 2m diameter - concrete could offer much bigger spheres... big enough for a autonomous deep diving sub wall thickness of >1m impossible to do in other materials - normal concrete would probably be limited to 1000-2000m - your superstrong concrete could go down maybe 5000 m or more.

- economically feasible - would be by far cheaper than any alternative i can think about...

Kindest Regards,
W.Ellmer

W.Ellmer [boatbuilding forum]

submarine mega yacht - a different aproach

Hi i really would like to work on a project like this...

I understand the question of viewports - they are expensive - you have to change them after 10000 dive cycles they are hardly to integrate in a streamline shape. just get a couple of camaras and a wall of plasma screens and you will see a lot more around your sub as you would see trough viewports. Carsten made this point clear latley in psubs.org.

A couple of months ago i discussed with carsten (merlinsub) the idea of a sub made of a series of concrete spheres as pressure hull and outer streamline hull without viewports this boat could go VERY deep - carry a big ROV for salvatage - and you could cut one of the spheres in half without weakening the hull opening it on surface as a helicopter hangar...

My proyect : Concrete Submarine Yachts

you could build that kind of sub in floating status similar to bridge foundations of golf of corinth...no shipyard needed...

You could build it VERY big... see platform leg below ...

W.Ellmer

---------------------

Location: Ontario

Not a bad idea at all... I seem to recall that back when Boeing was all high on Sonic Cruiser hype, they were talking about replacing the cockpit windows with a set of big flatscreens, that the pilots could switch between different cameras. Makes a lot of sense there, you can't fly a fast plane like that VFR anyways even if you wanted to. And it would have let them streamline the nose a lot better, without the Concorde's mechanically nasty hinge mechanism. The same principles should apply to a sub, I would think.
-Matt-

----------------------

replace viewports with camera

On a big sub you also might get better view in infrared or by this new development of acoustic camara that gives you a image made from sound reflections. You also might need to send out a ROV to cut your propeller free which is not in sight of any viewport. It is like starship enterprise - put it on main screen...in near future you also might opt to navigate with a simulated landscape - based on boat position and geo-databases like in a flight simulator.
You also might do a couple of hundreds of detail shots with the ROV on a shipwrack and then mount the photos together to a clear overview on your screen just as if poor visibility would not exist - we have seen that from Titanic... A well mounted camara system gives you a picture you could never get trough a viewport - especially on a big sub.

Kindest Regards
W.Ellmer
----------------------

Thijs Struijs [psubs.org] 11 Feb 2007

concrete submarine yacht

Hello Wilfried,

That's a great sub you built. What's the status of it now? (Did you sell it?Is it still in Austria or did you ship it to Colombia?) Before asking you questions i suppose i should read your bible to acquire some basic knowledge. But there are a view questions i would like to ask you right now.

1) Is the hull made in one piece or did you glue two cones together?

2) How did you make the mold? I suppose you used an internal (male) and an external (female) mold. How do you prevent the internal mold from floating in the wet concrete? Could you remove the internal mold after the concrete had cured and schrunk. Maybe you have some pictures of the building proces.

3) I suppose the viewports are seated in steel rings? Applying steel inserts in concrete constructions are probably common practis. I had better start reading right now.

Greatings,
Thijs Struijs
The Netherlands
-------------------------------------------

concrete submarine yacht, status, forming, viewports

Hello Thijs

Lake Atter is a alpine Lake with little access by road. There was only one site (you see it on the picturs) (http://tolimared.com/submarine) where the road comes so close to the water that you can place a crane there and lift a heavy submarine into the lake like on a pier.

Kindest Regards,
Wilfried

--------------------------------------------
Brian Cox 11 Feb 2007 [PSUBS-MAILIST]

concrete submarine yacht

Great to hear from you again ! I think your sub is the greatest ! I want to build one ! I better finish my current one first though. Thanks for updating your web site and keeping us informed.

Brian Cox, Ventura, California

--------------------------------------------
Hello Brian let me know how i can assist... i could build you a hull...

Kindest Regards,
Wilfried

--------------------------------------------

Øystein Skarholm / psubs.org / 11 Feb 2007

concrete submarine yacht - want to build one -

How long time will it take you to build a hull 10 meters long 2,5 meter Dia with 200mm thick walls?

--------------------------------------------
Hello Øystein,

concrete submarine yacht - building time. I can have a hull ready in less than 3 months and ship it wherever you want...

Wilfried
--------------------------------------------

Carsten Standfuss - MerlinSub 11 Feb 2007 / psubs.org

concrete submarine yacht, lift it

Hi Wilfried - its still yours, even as wreck - you are the owner.
How long is it now at dive station ?

So somebody from Austria or somewere in Europe can purchase it from you, raise it, clean it.. He can make an new interior and maybe with bigger ballast an trimtanks.. and use it.

Kindest Regards
Wilfried
--------------------------------------------

Oystein [psubs.org]
What costs are we talking about. Complete sub like your previous.?.

Hello Oystein

6633 Euro

Kindest Regards
Wilfried
--------------------------------------------
Wau... thats cheap.
Yust for my pleasure what will be a hull 16 x 2,5 x 0,18 ? Including 3 pressuretight hempispharical bulkheads..

regards Carsten
--------------------------------------------
concrete submarine yacht - building cost

Concret is a pressure tight material - and steel is at the moment unbelivable expensive.

I purchase my steel hull 16 m x 2,5m x 22mm in 2002 for 50.000 euro about 64500 USD. I would like to here what it is in concret for further projects..

Special for really deep diver were steel gets to thick and most supplier quit..To bend 200 mm strong steel to a shell is not easy and maybe really expensive - but to make the same boat in 500-800 mm concret should be no problem.

A ocean going psubs for 9000 feet..

For small shallow water Subs I still think steel is the better way.

Best Regards Carsten
--------------------------------------------

steel versus concrete hull

Hello Carsten,

Thank´s for confirming my argument that what makes concrete most convenient is the fact that steel forming ends when plates become a few cm of thickness.

I apreciate this from a naval engineer that is forming the worlds most exceptional private submarine from steel right now...

I have seen a documentation for the virgina class submarine where they roll thick steelplates on building site in red hot status to form the hull.

Imagine cost ! - well that is US military - and imagine a process for a sperical pressure hull of several centimeters - trieste had one of 2m Diameter formed from 3 pieces at krupps super cannon facility - was the only site in the world which could do it !

For your 9000 feet deep diving autonomous sub we are talking of wall thickness of about 1m - i can not imagine any other material than concrete in this.

Kindest Regards,
Wilfried
--------------------------------------------
Hello Carsten,

Just add some 6633 Euro for each 20 tons of displacement. If you have a double hull in mind make it some 8000 Euro /20ton for increased complexity in building. I can make you bulkheads. What is about the deep diving sphere pressure hull boat we talked about ?

Kindest Regards,
Wilfried

Oystein - i can get you a engine in and bring it to norway with the golf stream- Ben Franklin did that...but make it bigger than 10m ...

Kindest Regards,
Wilfried
--------------------------------------------
Hello Øystein

What concerns transport we have 2 options:
1 build the hull in container shipment dimensions.
2 make it a little bigger suitable for ocean crosssings ( some 18m ) and put a diesel in to bring it up to Norway on its own keel.

Let me hear your thoughts...

Kindest Regards,
Wilfried
--------------------------------------------

Øystein Skarholm
If the boat gets to large than it is no longer an recreational boat. For me the boat has to be simple to use and cheap to operate.

--------------------------------------------
Carsten Standfuss

Yes Sir! Thats exact the reason I build the Euronaut.
Simple to use and cheap to operate...

Original I looked for a cheap old military one..but they all are not simple to use and not cheap to operate. If you want to make recreational diving in 600 feet deep this 70 tonner is the minimum configuration..

I think there is no border for recreational. If it is private build, with private money and with no commerzial background - it is a Psub..

best regards Carsten
--------------------------------------------

autonomous concrete submarine operation

Carsten, Oystein, Juergen, listeners...

To nail down the details we have to be clear what is the VISION.

I think what we all found is that doing investigation in the oceans is limited more than anything else by the BASE you can work from.

This is why carsten is building an AUTONOMOUS submarine dive base of 70 tons. Which is the most advanced project we know about.

But think about it - 70 tons of displacement is 70m3 of living space that you have to share between crew, equipment, machinery, dive instalations, cientific equipment, dry/wet rooms etc... can you do that and live there - for several months without going for a port? - probably not.

What you need is a oceangoing submarine living and working space - so if you could forget the limits - how big must this space be?

.. more or less the size of 15-20 m yacht? - more ?

how can you reduce the operation cost of such a space to a minimum ?

Basicly this problem is the same as oil drilling has - how do you get a autonomous drilling operation at sea...to big to get it out and painted like a boat once a year...

What are the operation cost to have a giant concrete structure parked at sea ? (cero - if you don´t have to take it out for painting and other maintainance and don´t need a marina - can resist any weather - a submarine could !) -

How much material you need to build such a thing ? what is the cheapest and most durable material you can imagine for such a purpose ?

What if you build such a hull in a country where work is cheap and ship it to europe for finishing - if it would be big enough you can live and work on board ?

What if you would not finance such a project from your own pocket but find a group of investors - sharing the same vision - sharing the risks - being linked to the project - by company shares - see CENTRAL AMERICA project as a model.

If you could offer a 2000m diving autonomous sub with ROV oceancrossing - selling investigation time - to scientist - oil operations - salvatage - goverment - tourism - private - would capitan nemos nautilus be a profitable business - traveling round the world from job to job... could we nail down a "business plan" to convince investors ?

What kind of team you would need to move it forward? Could we assamble such a project over internet ? How would you do the marketing for such an operation ?

Let me hear your thoughts...

Kindest Regards,
Wilfried

--------------------------------------------

living space in a autonomous submarine

Not size is the limit - money is it. A 70 ts submarine can not have more as 30-40 m3 living sphere. The free square meter m2 in Euronaut is about 10 by 2 meter so 20 m2 meters or 5 m2 for a crew of four and for each person. Plenty of space - a german WWII submarine has less - and the stay transatlantic and back for months...
Not easy for sure. The Euronaut can be operate in sonar modus by a crew of two and in diver exit modus by a crew of 3-4 people.

Carsten
--------------------------------------------

living space in a autonomous submarine

Carsten, i agree that your euronaut is the best on autonomous privatly financed submarine living space that is available - great job ! I also agree that 5m2/ man is a big living space compared to ww2 subs - also your 70 tonner will be able of transatlantic oceancrossing. I really want to see it operate and i am sure you will push it forward.
please contact me at info@tolimared to discuss a project...
Wilfried
--------------------------------------------

trailerable submarine / autonomous submarine

This thread is very interesting! One thing you give up with a concrete hull is transportability. I can pull a K350 with my F250 pickup.... not so with a concrete sub. On the other hand, a concrete submarine would be a submarine and not a submersible.
Gene Seus
--------------------------------------------
trailerable submarine / autonomous submarine

Hello Gene, 3m3 of space is a 3ton sub - this is still a coffin size - but yet hard to trailer - trailerable is impossible for a real autonomous sub - a weekend living quality similar to a small yacht starts somewhere at 20 tons for 1 person - add a diverlock and a 3 man crew - 70 tons - minimum - see euronaut.
Wilfried
--------------------------------------------

stress levels in a concrete submarine yacht hull - troll

The diameter of the legs on TROLL platform is approx 24m. The wall thickness is 1m. This platform stands 303m under sea level. Not only shall these dimensions take the static pressure but also the dynamic forces applied by wind, waves and underwater currents. The hull thickness of TROLL is approx 4,2% If you make a sub 200mm thick on a 2,5 m diameter hull you will have a thickness/hull diameter of 8% That is almost twice that of TROLL :-)
Oystein
--------------------------------------------

stress levels in a concrete submarine yacht hull - troll

Oystein, this calculation takes my sub to a working depth of 606m - anyhow i would not trust the viewports for such a depth... but this shows that you can get manageable stresslevels similar to TROLL in a concrete pressure hull that goes to 606m with a yacht configuration - still not using spheres as pressure hull as in deep diving configuration.
Wilfried

--------------------------------------------
Hi Wil

I just looked at your website for your concrete submarine. Its a really really great idea. I had not considered building a boat out of concrete, but reading through your site, it seems brilliant. I'm currently building a K350 submersible with all the problems of working with steel. I kind of wish i'd stumbled on your site earlier. It may have been more usefull to build something similar to your own. You certainly can get something bigger made easily. Steel is expensive, and difficult to move around. But i assume with concrete, you simply built a wooden mould and poured the concrete in? Anyway, can i ask you a question thats not on the site? How did you mount the viewports, hatch, throughhulls etc? I assume there are steel parts moulded into the concrete hull?

Look forward to hearing from you.

Thanks
James

James Frankland
--------------------------------------------
Hello James, Thanks for your kind words.
I updated the website with some of the points you are asking for. Yes you get a lot more submarine at a by far lower cost in concrete. Have a look at TROLL platform (see it on internet) you do not build that kind of things by making a complete inner and outer form for the whole structure - you could not compact the concrete during pouring in - you get a "slip form". Kind of ring that moves on from base to top. Just do it horizontally...You can mount steel anchors in concrete. I did the viewports with concrete seats as i did not want to have a point where forces interrupt on a steel ring - worked fine.
Wilfried
--------------------------------------------
...i better finish my K350 first before is start making a massive concrete giant!
James Frankland
--------------------------------------------

concrete submarine hull sand and gravel

Wilfried, Where you plan to build the concrete sub, what is the quality of the sand and gravel ? According to concrete experts that I have talked to this is very important for the ultimate strenght of the cured concrete. For instance, here in Ventura California where I live, the geology of the area here on the coast, the rock here is not good for strong concrete. I have to make sure I get sand and gravel from the desert area where there are deposits of granite.

Brian Cox
--------------------------------------------

concrete submarine hull sand and gravel

...good point brian - in fact you need 3 groups of korn with certain specification of roundness and hardness to get good concrete any construction company can advise you in that - also test some cubes of the mix you use during building.

But most importantly - before you start building any submarine - have a good plan how you will run and maintain it, what you will use it for - how you will finance it what will be the cost of maintainance - similar as in yacht building you may opt to buy the hull - and build only interior by yourself - i had to build 3 hulls to figure it out - learning by making mistakes is cost intensive and dangerous...cut those costs.

Kindest Regards,

Wilfried Ellmer

--------------------------------------------

Big concrete Subs concept

Hi Wilfried.

Maybe I build a sub after Euronaut - maybe not. At the moment the progress is slower than expected..I am far behind my timetable. Its a big project for a single person and even just a cold nose as today keep you back one week.

I have a concept for a cheap, big, fast deep diving concret sub. As Psub. A 6000-9000 feet diver. Some 700 sm range dived at 7 knots in any deep.

The problem is that I have to go to work 5 days a week and have only the weekends for diving and subs expeditions - and some hundred seamiles around my country the sea is not deeper than 900 feet. A deep Euronaut can easy reach.

So, this big concrete sub deepdiver will be intressting for me in the time area were I retired from work in about 20-25 years. Thats a good time for a new sub because Euronaut gets also older during this time. Maybe I can sold the Euronaut during this time to build the big concrete shark.

So I think I will start planing this big concrete sub in about the years 2020-2025. Concrete is maybe the only way for me to see the deepsea. Steel/other metals gets to strong and/or to expensive.

My new homepage is under conctruction and will be later a page with drawings concept of unuseual submarines like gliders or deep concrete subs. We can discuss this concepts than. Wilfried I think if you want to sell concrete subs hull it
will be wise to make some FE-Study before.

Something like:
- boat under 2000 full pressure loads and deloads.
- boat under full load for weeks
- boat from zero load to full load in very short time
- boats diver chamber under 2000 loads in both directions
- impact studys at harbour speed, impact studys at full speed

I think to get a good quality concrete sub the total boat has to be designed with all troughhulls and anything has an influence to the hull before the first concrete will be mix. This is complete differnet from steel building were you can start with something and end with a complete other result - like Nemo shows. On a steel sub you can work more or less with the trial and error methods. Easy to fix with a grider, a torch and a welder. On an concrete deep diver this will be much harder I can imagine..

best regards Carsten

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Big concrete Subs concept - finance -

Hello Carsten,
...Its a big project for a
single person ...

One of the things i have learned as Manager in Multinational Companies is that if you have a project that has a potencial there is always the money out there to make it happen.

So i am sorry to say it so directly but the weakness of euronaut project is not engineering - it is the fact that you try to lift it all as a single person.

If you wait to get old and retired to take your dreams a step further you probably will get just that - old and retired - .

I would like to suggest such a project to possible investors right now - would you join in such a project ?

Kindest Regards,
Wilfried
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Wilfried.. A more reasonable answer: If you like to make a study for a sub faster and deeper than anything else available (without nukes) than looking for a combination of concrete hull with Lithium Ion Battery or/and Fuelcell drive in combination with the new high efficency electric motors. Safe some money on the hull budget and spend it for the hightec drive..

Go with the idear that the water tanks, hard and soft but also the gas and fuel storage tanks are just caves in the concrete and make the hole concept integral.

regards Carsten
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Wilfried, I think with a crew of more than say 4-5 persons things start to get a little more complicate. If it is nessesary to pay your crew - thinks starts to get a little out of Psubs disscusions - right ?

The decision about the hull construction material is less than 20 % of the disscussion of a big autonomus submarine. Only one point of many others. If you find a client which want to pay the project - I am in the next day !
regards Carsten
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Wilfried, Where you plan to build the concrete sub, what is the quality of the sand and gravel ? According to concrete experts that I have talked to this is very important for the ultimate strenght of the cured concrete. For instance, here in Ventura California where I live, the geology of the area here on the coast, the rock here is not good for strong concrete. I have to make sure I get sand and gravel from the desert area where there are deposits of granite.
Brian Cox
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concrete submarine hull sand and gravel

I can state where and how i do a project when i have size, requirements and budget - this is why i say before you start - have a plan - write numbers down - share your numbers with other people to see if realistic ... do not make a boat first to figure out later what to use it for...

Kindest Regards,

Wilfried Ellmer
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Hello Carsten

...If you find a client which want to pay the project - I am in the next day.

Here we come to the central point - if you want to atract investors to a project you need to have yust that - a project that makes sense - that has potential to make money - because that is what investors look for.

Investors are not interested in a submarine they are interested in your plan what you do with your submarine to make money.

They are not interested in a diver lockout they are interested in you capacity to reach something you can make money with.

They are interested in the business aspect of your operation.

So if we can put together what is the business of having a deep diver with live aboard quality for 4-5 persons - and visualize it - we can share this VISION with potential investors and get the money for the project - the money is out there - but we need a project to atract it.

Wilfried
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concrete sub - easy repair

Just a thought....How do you know you don't have bubbles or other voids in the pour, if you can't see it? Would a vacuum pump work to suck out the air as the cement is being injected? Sorry, but I'm a welder, and like the idea of steel hulls. If I want to add something, or repair the hull, or even cut in another window, I can break out the torch. Is it possible to cut into a cement hull? The main advantage I see of a concrete hull is its compressive strength. Just seems like it would be hard to modify later.
Frank D.
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concrete submarine impact resistance

I am intrigued by what Wilfried has accomplished and would really like to explore further the possibilities. To lessen the impact issue, consider metal-skinned, external ballast tanks that vertically extend down below the greatest breadth of the concrete hull. The metal acts as a fender and is more forgiving of impacts than the concrete (easier and cheaper to repair also).

After sailing as the engineering officer on the largest ferrocement vessel certified for hire in the US for a year (I recognize the difference between ferrocement and what is being proposed here) and having to repair a significant hull breach due to the captain at the time's inebriation (drunk), I concur that the hull thickness should be designed greater than what is required for depth. The vessel's hull in the region of the accident was properly laid up with a significant amount of rebar which held together the crushed concrete but a large amount of water still flooded into the hull. A freshly tarred piece of canvas pulled around the hull and over the breach staunched most of the flooding until repairs could be made. The square-rigger was 130 ft. (40 m.) in length, displaced about 200 t., and the hull's ferrocement was about 180 mm in the region of the hole. The collision was with a channel buoy (a giving instead of a solid surface) which crushed an area about 20 inches (0.5 m.) in diameter. The crushed concrete had to be cleared out, the exposed concrete surface cleaned with muriatic acid, and a VERY EXPENSIVE special epoxy-sand mixture was used to fill the area which resulted in the patch being stronger than the surrounding hull.

R/Jay
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concrete submarine impact resistance

Yes - An thin metall large ballast water tank as impact zone in the bow area is maybe an idear for a concrete sub.

Another idear is maybe a thick PU (Polyurethane) layer (a rubber coat) of some cm thickness on the concrete. Keeps the pressure saltwater away from the concret and helps against smaller sharp impacts.

I have seen pictures of a 12 meter (30feet) sailing vessel made from thin ferrocement - get on the rocks during bad weather and was destroyed into small pieces within minutes.. On the next day the bigges item has the size of one square meter or so.

But we talk about 0,5 - 1,0 meter concret on a about 20 meter vessel.

regards Carsten
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concrete submarine - let form on hull

Jay, Wilfried, and all, Since I'm getting ready to plaster my ferro-cement hull soon I'm intrigued by all thing cement ! I've been investigating some of these large concrete pipe manufacturers here in California and I'm thinking of having them do the concrete mix and pouring. (for my big concrete sub) The idea I have is instead of making a wooden form, inside and out, to hold the concrete while it is curing, is to instead build a ferro-cement form inside and out. Then, once the concrete is poured and cured, the ferro-cement form is simply left in place and becomes part of the sub. This way there would be no need to remove forms. Another advantage of doing this would be the interior details could be worked on before the structural concrete was injected inbetween the ferro cement walls.

Brian
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concrete submarine - let form on hull

Hello Brian, forms that stay on hull is not the way they do it in drillrigs, tunnels, towers etc... may work - may not - see big problems in compacting ... slip form is how engineers do it.
Anyhow if you do something non-proved let me know how it results...good luck!
Kindest Regards
Wilfried
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concrete submarine yacht hull - steel skin

The metal skin idea seems like a very good one, you could possibly even use fiberglass, because it would just be the equivalent of a streamlined second hull to absorb minor impacts. with your cement primary hull being the only preasure hull, I don't see any reason a good fiber secondary hull wouldn't work. be a bit cheaper too. You'd have to have some sort of structure to provide for a gap. Maybe some sort of rubberized/plastic external bulkheads/ribbs? that don't actually penetrate the hull but simply rest upon it... almost like a suspension off a car or large truck.

George H. Slaterpryce III
www.captovis.com
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concrete submarine forming blimp shape

Hi Brian. Did you see the pictures that Wilifred had here of his concrete submarine? I was really impressed with the size and especially the shape. Quite an achievement. As to the voids, a vibrator is the only way I know of to get out the bubbles, regardless of how you form it up. In the thread, he mentioned compacting the concrete. I don't know what that means. If you are seriously considering making a concrete sub, ask him for advice, sounds like he knows what works.
I got confirmation yesterday from the steel shop about my sub hull parts. They are shipping on the 28th. I'll be posting pictures when I start assembling them. Good luck on your project.
Frank D.
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do a serious concrete sub project

Wilfred, Why don't you build a sub for a purpose to make money and then sell the sub and the business you have created all together.

Brian
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do a serious concrete sub project

Building something like a submarine with your own money and a vage hope that "somebody might buy" it later is bad business practice.
Especially if you think about who would buy a submarine - military? - certainly not they build their own - scientific? - they would like one but have no money etc...
So as a concequence most private submarines end up in a backyard although they may work very well.
What you have to do is come up with a proposal and then see if you get a customer. If you get a customer you start to build.
To do that seriously you have to do something like a "pilot project" that shows that your concept can work. Well i did that - the information is there on my website [http://tolimared.com/submarine] - so far i got interest for a deep diver for salvatage for a submarine yacht with yachting purpose and for a stationary hull with big viewports for tourist purpose. Which one i will build depends on which project comes up with a solid funding.

I really would like to find Investors for a project like this:

Build a hull, staff it out with a diesel, basic dive capability, and fine leather interior - then yacht around in the caribbean and collect interest and more construction orders. - Finally found a specialized shipyard where concrete hulls of different size and purpose are built in series...

But i can not lift that as a single person. I need people with financial capability to share that VISION and to put "risk money" to make it work. - Can we get money out of the concept of "Submarine Yachting" - of course - can it be a business - of course a tremendous one - but who believes in it and is willing to put money - the tecnical problem is solved - the business part is still waiting...so this finally does not break down to solve a relative simple tecnical issue - submarines are around for at least 200 years... it is a question of making work the business part.

Kindest Regards, Wilfried
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submarine market analisis

Years ago while in grad school for Marine Affairs (policy and management) and tourist subs were a hot number, did a study of how big the market was. Conclusion it is a very small market and there were only a handful of sites around the world suitable for conducting tourist sub ops. A successful sub depends on a high tourist through-put, a high passenger loading factor (how many seats of full capacity are filled), a high seating capacity (numbers showed that a 15-passenger tourist sub would have a hard time covering costs), and a heavy operational schedule (multiple trips per day and most the days of a year). This was proved out a short time later by the high number of boats going out of business and orders for new subs being canceled.

If you read Busby’s commentaries, his book was an effort to document all of the subs in the heyday of submersible building. The late 60s saw a ton of units built in the expectation of a burgeoning undersea lifestyle. He recognized this wasn’t happening and it was turning into a bust market so he collected all of the designs he could and documented them in his book. Very few subs in his book were around long.

Much like diving, submersibles are a tool to meet an end. Unless you have a specific function for the sub, most get laid up after a short time. Most PSUBbers are in it for the challenge, comradery, and knowledge gained along the way. It takes a lot of work to make a dive in a submersible, you just don’t go out for a joyride and sightseeing as you can in a small power boat. Prior to a sub outing you have to get HP air and charge the batteries, have to perform a thorough systems check prior to and after launch (it is amazing the things that can come loose towing a sub on a trailer), it is a major operation to launch the sub (how many are kept in slips?), then it has to be slowly towed out to a dive site (few have something that is really interesting to see or close to a launch site), a tow back to shore, a haul out, and the trip home where the sub has to be cleaned up and washed down. This is a MAJOR evolution for the average guy (haven’t seen any women PSUB members, subs have to be a guy thing)! There just isn’t a great big market out there that can sustain regular production.

BUT WE LOVE OUR SUBS!

Jay K. Jeffries

Andros Is., Bahamas

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tourist submarine working conditions

In my observations regarding money making tourist sub operations. It appears to me that the location is the necessary ingredient to a successful operation, not the sub itself so much. You need a constant flow of "willing" traffic.

Take Karl Stanley in Honduras for example. Not likely the locals do much recreational subbing, and just having "tourists" is not necessarily it either. Who are these tourists? I suspect most of Karl's passengers are the adventurous "globe trotting" diver crowd.

Same thing in the Caymans and Hawaii, it's "who" the tourists are, along with the numbers that will make or break you.

Joe
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tourist submarine profit

Well said Jay, and all true. There have been quite a few companies started up to build subs, for recreation, but to date, I don't know of even one that ever turned a profit. We love our subs, but it's a small crowd. Eventually, mankind will use the sea for recreation, serious mining, large scale farming, etc. but at this point, it's just too expensive. And the world's governments don't like the idea of people doing things where they can't watch us. So for now, Let's use the freedoms we have, and go have some adventure.
Frank D.
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tourist submarine profit

Jay, well spoken - what it means to make a simple dive in a psub . This is why having a 40 tonner concrete submarine yacht on a bouy is less cost and easier maintainance weekend diving than having a 2 ton "psub" on a trailer.

Wilfried
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