Spar design versus flat raft platform design
July 18, 2010 at 9:22 pm #10841
going completely in the direction of a raft? Their design was most definitely a ‘raft’ drawing 20″ of water while your design has the look of a ‘displacement’ type hull… Below is a link where it is discussed how certain problems were solved:July 20, 2010 at 7:35 am #10867
No I didnt. One of the reasons why, was described by Poppa himself: “Our biggest problem was getting the raft to steer downwind. With a flat bottom, and drawing only 20 inches, there simply was no resistance underwater. Every time the wind went over 15 knots, the raft would turn sideways. This obviously would not be safe at sea, and our many attempts to solve this problem nearly drove us to despair. After literally years of testing and redesigning, we finally solved it by installing a huge retractable daggerboard at the stern, just ahead of the rudder. This, together with a very small storm square sail hoisted at the bow, effectively turned the raft downwind under all circumstances.” Which is very true.
But initially I didnt have sailing in mind for these modules….They were meant to be powered @ low cruising speeds, 3-5 knts. Later on I said to myself, “hey, but I can sail them @ that speed”, stepped a short mast on them and rigged some sails (or flexible solar panels) and came up with the “Solarsailstead” design. http://seasteading.org/interact/forums/engineering/structure-designs/solarsailstead. Even without the “solar” part, and just as a sailstead, the concept makes sense by saving a lots of green on fuel. I kept the underwater design the same, since I already had a bit of flare there, (acting as a shallow keel) and since they won’t race the Transpac. it would be ok. On second thoughts, and since you brought it up, looking @ the waterline view, I might need a small centerboard there, and maybe a bit more sail area.
Going to a flat bottom raft? and use a daggerboard like Poppa? I dont know. A mathbox wont sail to good… I was trying to keep @ least some degree of hydrodynamics in the bellow the water hull configuration, and actually I was thinking of adding a bit more flare both forward and astern and increasing the draft. Keep in mind that the lower the metacenter the better stability. Why would you consider a raft? I think this design its a bit of a mutt, raft-displacement hull.July 20, 2010 at 2:08 pm #10870
You have heard of sea drouge’s right? we use em in life rafts.
its like the 3rd thing you do after you get into the life raft to stop you drifting from where your ship sank. (& your last panpan)July 20, 2010 at 2:33 pm #10871
Ocean, i think we will see a lot of different designs for a lot of different purposes. There will be 2 mayor currents – stationary designs – mobile designs. To be more specific the stationary designs will possibly still move (with the currents) but they will not move relative to the surrounding waters and this for a good reason – (aquaculture nets hanging out close connection to the local waters). The mobile designs on the other hand will simply be yacht like or cruiseships like or vehicle like, and work as such.
If you go for cruising of 3 knots you already can go with a stationary design because the contribution of the current will be close to 3 knots anyhow you will have more speed from “choosing your location in the existing current wisely” than from “cruising through the water”.
On the other hand a seastead with a strong emphasis on mobility may just be a catamaran built out of concrete shell to make it more affordable and independent from yacht infrastructure. Or it may just be a blimp shape semisubmersible. In other word a existing hull design made more affordable to achive massification of the market.
The risk of doing a kite design or any other “semi mobile” design is that you are going to sit between two chairs. Not enough steadiness to bring out aquaculture nets, not enough speed to travel around decently.
I think we will not see a lot of “new revolutionary shapes” on the water for seasteading. We will see a kind of “gradual evolution” of waterfront developments and “yachting” towards less exclusive and more massive society segments and a blending of existing concepts like floating fishfarms, yachts, floating marinas, industrial offshore installations, load terminals, –
All those installations today have two mayor shapes.
1) Big modular stationary flat floats (oil load barges, marina walkways, floating bridges, cargo terminals, floating airports, floating LNG terminals and process plants, storage tanks, etc…)
2) Hydrodynamic shell structures (yacht, ship, submarine, mobile platforms)
The best way to predict the future (of some 100 years) is to look at what is invented already and imagine its massification.
European Submarine Structures ABJuly 20, 2010 at 4:42 pm #10877
seems to be defined in most of the cases by our present actions. There is no doubt that “any shape” floating object can travel @ 3knts. The Kite design was a study in modularity and mobility. A compromise. (Still, with that underwater hull configuration will do 8 knt cruising speed). Beyond the point, and I do get yor point that there is really no need for a new design, but a new aproach towards “seasteadification” of existing designs.
Well, then, the most sensitive thing to do would be the conversion of decommisioned cargoships. Hundreds are lined up to be scraped off Singapore. Offer 1 penny more/ ton (they are already pennies to the dollar) and start there. Yes they are steel,… so what. For the price, we can patch every rust hole with epoxy for the next 10 years and still be ahead of our game. Raft up 4 of them and in 5 years we’ll have fun and make $millions. When we’ll “run out of epoxy” will “run them aground”, (blink-blink) on a shallow bank in the Indian Ocean as artificial reef-island and flood the bilges for good. And still make money after that. If Mauritius or Tonga or whoever EEZ we are in they dont like, tough luck, it was an “accident”. If they want removed by us, oh well, we are broke. They wont spend 5 years worth of their GDP on this salvage. They wont call our bluff and they’ll reason that its better to “work with us” on this one for 5% yearly “divident” on our net income.
Seasteading boils down to dollars and sense, as you said it on a different thread.
P.S. I still like my “Kite” modules. They’re my babies, man.July 20, 2010 at 5:29 pm #10879
ocean, if rafting up city block sized structures would be a viable option the ship-scrap-raft would probably be a solution – at least a temporary one until all sinks down in a sea of rust (some 1-5 years depending of the initial status) ships are extremly maintenance dependent structures that only make sense if they make serious money in transport – every hour a ship is not moving is a netto red number. So a ship seastead would be red numbers and rust as only outcome.
Wohl has a point when he points out that most floating structures that are out there for “private live aboard purpose” are just some 30 feet (10m) in size (yachts). There is a good reason why that is so. The actual size reflects what a real person can afford and maintain. We can not choose freely how big and fancy our structures will be. The limit is a mainstream family budget. What we can do is optimize the offer so that it translates into less bliz and shine but more honest living quality and living space than the Yacht industry is offering. Yacht industry is focused on “appearance” on “show motor power”, “exhibit luxury” – seasteading for mainstream will be more like a houseboat, a asian floating market, a floating fishfarm, with little emphasis on bliz and shine and a lot of emphasis on practical solutions and easy handable, easy repairable, long lasting.
As the floating neutrinos point out the kind of structure that gives you most bang for the bug is probably some kind of raft. As we recently understand (Heyerdahl) rafts are much more seaworthy than it is commonly understood. So the most logic way to bild cities is to raft up family houses – and the most logical base module is a floating family house in the 10m size range – not a city block sized condo.
The existing way to “raft up” yachts and houseboats is a floating marina development with floating walkways, floating stores, breakwaters, etc…July 20, 2010 at 5:47 pm #10881
“LOL! Ya’ know, this whole site just goes round in circles…. We’ve said all this before… we’ll say all this again….”
Like the man says, took me 3 days to figure that one, how long for you?July 21, 2010 at 2:00 am #10886
I did talk about size in the other thread of yours, Will, and left it open for comments. But then, the conversation veered toward different subjects. I was saying,
“So far, we agreed on the following:
- The material of choice IS ferrocement (steel reenforce concrete).
- The construction of choice IS a modular capable float (MODULE) of the above material, of a size and shape yet to be determined.
- The size of a MODULE is ?_________ sq. ft.
So we have to work on the size now and then shape. How big, or actually whats the minimum size for such a SFS? Now we have a problem,…because everybody’s “taste” is different.
I have a 23′ LOA X 8′ BEAM cabin cruiser. 180 sq ft of living space. It has all the amenities to liverboard and go costal cruising and I am comfortable on it. This is because most of my life I lived aboard. Is this the norm? If not what shud it be? Can we really standardize here? We will have to! Because size and cost will depend on it.
How about 250 sq ft / person?
Now, what is a SFS? A couple and 1 kid? 2-3 kids? 1 person? 2-3-4 roomates?
Is there a “under the sun” allowance, like a sun deck, yard?
How about 50 sq ft/ person.
Total= 300 sq ft/person.
Lets assume that the SFS Module will be build as big as the equivalent of space for 4 people.
1200 sq ft. Thats it! That’s a square module 35′ x 35′. (build a second deck on top and everybody’s living large !)
Is that the right size for you guys? (forget about the shape for now).”
I am all for houseboats. The MMK (Man Made Key) Project , part of OSDI was all about rafting up 4 30′ houseboats to create a Seasteading Outpost.
But 30′ is small for a SFS. Pls trust me on this one, specially when it is for a couple. Chicks need space, they have shoes and issues. I am not kidding guys. I am talking from experience!
A 1200 sq. ft houseboat (main deck) with a second deck upstairs (around 1000 sq.ft) would be around 47′ LOA X 25′ BEAM and accommodate up to 4 people comfortably.
How about that?July 21, 2010 at 10:37 am #10887
Is there no Poll system on this forum? that could help you answer some of your questions Oceanopolis,
I would want 244 sq ft for my own room to be content, but i would share that with my wife.
people have to have a little space, so If i had kids i would expect them to get 240sqft each also.
Your cabin cruiser sounds nice little pleasure craft, but no thats not the norm, I would say most people dont have anything near that experiance, hell i dont & ive done seasonal yachting work.
I would buy a self contained building that could weather the worst & keep my family alive at sea.
However If you keep things small say down to 50sqft PP or less you could probably rent mini apartments with communal cooking, wc/shower & living areas, that would be ok for short term rents, not long term, but since your talking about long term, I would say your going to have to go bigger m8, please.
p.s do you intend to have each caisson self sustaining, for example generators, waste disposal, water storage etc?
If you do then i think they will be ALOT more exspensive per caisson than a regualr house build, & would take longer than simply building a house on a cassion with sockets to plug into a central supply.
If you do care about efficiency & Cost, then you will be making these house caissons dependant on an external source of supply right?.
so before your built one of these house units, would you not need:
July 21, 2010 at 5:35 pm #10889
- Power Station, Caisson Barge
- Water Treatment & Pumping Caisson Pant
- Waste Storage & Disposal Caisson Barge
- Supply Store & Depot Caisson Barge (if its an outpost like you say)
Posted a link on another thread concerning the minimum space requirements for long term confinement (over 2 months) based on NASA studies. From reading the results were that an average presumably disciplined person requires a minimum of 600 to 700 cubic feet. That works out to a 9x9x8ish foot space totaling 648 cubic feet. The reading didn’t get into space utilization issues but we can assume that because ‘space’ in space (or a proposed SFS) would be more 3 dimensional than it is here on earth that the ‘space’ was totally utilized for efficiency’s sake. Further reading stated that as with the number of people the minimum space requirements per person go up but didn’t explain how, why or how much…
Jack, I think we all figured that out pretty quick but I just think that someone has to ‘say it out loud’ from time to time…July 21, 2010 at 6:08 pm #10892
9x9x8 is a prison cell (actually smaller). I would have hoped that we can offer a bit more than that man. We are not sending men on a galaxy far, far away,…Is it 300 sq. ft/ person tooooooo much to ask?
Now, to all of you.
All I am trying to do is find out what the general consesus is here regarding the size of a Module, built as a SFS.
So we can move this conversation forward and keep it constructive.
Just a number,…in sq.ft, assuming 7 ft headroom. It cannot be that hard….July 21, 2010 at 7:06 pm #10894
Ben Franklin had 130 cubic meter living space (submerged) for a crew of 4. They made a trip of 1 month in complete insulation and it seemed to work quite fine – according to the logs it was more a “expedition experience” than a “survival experience”. The submerged habitat we are building at the moment has 200 cubic meter of living space, room equivalent of a 68 squaremeter apartment. So it will feel comfortable during long time periods for a family crew. (almost twice the size of Ben Franklin).
What concerns flat raft solutions i would consider 6m diameter a minimum – not because of the space available, a smaller raft would still have a chance to get flipped over in open ocean conditions. A 6m diameter raft shell structure can be built with 9 tons of concrete shell building (cost some 3000 USD) – if you distribute the space smart, (underdeck, deck, flatroof,) you will get the space equivalent of a 40 squaremeter apartment. It would be more flip over save than a normal yacht in the 30 foot range, have a higher impact resistance, better fire resistance, better store capability, much more comfortable in movements (no rolling), superior sink resistance (chambered), sacrificing the “bliz shine and speed” of a normal yacht . This would be the “version for the poor”.
The “family house owner version” would be some 20m diameter some 200-250 ton concrete shell building (cost 82.750 Euro) in structure – room equivalent of a nice family house.
Artist vision video of this piece:
In general i would say space should not be too restricted as the ocean is big enough to spread out – a floating housing solution should be at least as “spacy” as land based housing. The challange is to achive a relative big structure that offers plenty of living space, gradually expandable, with cost effective means. Yachting industry is not working well in that field we can do much better.
European Submarine Structures ABJuly 22, 2010 at 4:04 pm #10907
You’re wrong on that being smaller than a prison cell… I’ve recently returned from a trip where I lived in a 12x12x8 foot space (144 square ft, 1152 cubed) and found it more than adequate. Had I been aloud to store and cook my own food there, it would have been great. I did have well equipped ‘common’ areas to share with others for dining, recreation and work etc. though. At one point there were 3 of us living in that space and it was set up to house 4! Now, I admit that it takes disciplined people to live in those conditions and it would be too much to ask of normal people so I’ll concede the point. Assuming a nuclear family of 4 individuals at 300 square ft and 7ft of head room equals 8400 cubic ft, utilizing your design plan, how big would it be?July 23, 2010 at 3:30 pm #10920
on the prison cell: in older facilities like the one I worked in, cells were generally 6x9x8 contained a combination toilet/sink one rack and a small combination desk/seat. Due to overcrowding sometimes 2 inmates were crammed into that space but not often. As you can imagine, it was dangerous. As for the 12x12x8 foot I recently lived in, I only did it for 45 days. Due to rank and blind luck I got that space to myself for about 28 of those days but others have done it, two in that space with as many as 3 or 4 from time to time for as long as 18 months at a stretch. Miserable, yes but nowhere near as miserable as tents! In any case, I concede the point: regular people couldn’t live like that and I wouldn’t ‘choose’ to live like that ‘forever’!
So, 60’LOA, 30′ wide? That is within the realm of do-ability!July 23, 2010 at 10:30 pm #10924
Your some peice of work Wohl lol, saw your profile OMG, This prison, you were uhm a guest right?
Oceanpolis, is those white things on the green “Deck” ment to be houses?
I’m not even going to ASK what Valium is.
What would you chaps mind telling me is wrong with putting your money together as a foundation? Then fabricating one large unit, it would be safer & give you greater savings on costs, not to mention you could have a larger communal outdoors area, or private plots on a larger single fabricatoin.
even the TSI is looking at this from what ive read.
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