Potentially Stupid Concept (Houseboat?/Landingcraft?)

Discussion in 'Boat Design' started by LLL003, Dec 13, 2019.

  1. DogCavalry
    Joined: Sep 2019
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    Location: Vancouver bc

    DogCavalry Soy Soylent Green: I can't believe it's not people

    Sorry pal. Wrong. It's loved by guys who can count last 10 without taking off their shoes.
  2. Ilan Voyager
    Joined: May 2004
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    Location: Cancun Mexico

    Ilan Voyager Senior Member

    Unhappily DocCavalry is saying some hard truth. I'm an old unbeliever of wild capitalism, institutional greediness, and the belief that concentration of the wealth is good for all. Cars and luxury yachts specially motor ones leave me totally cold. I've lived simply without air conditioning in a tropical climate, and i do not give a s..t to useless gadgets. I do not need a thermomix to make my loaf of bread...
    The capitalist green-bashing of the endless economic growth wants to make believe that some advanced techniques will clean up everything and that the first world will keep its expensive and wasteful way of life will continue forever. For example you buy a the 50000 bucks with the three years leasing 2 tons electric car and you save the planet.
    The first problem is the production of energy. There is no free energy, or even low cost energy. Energy has always been expensive if the cost is taken in its global reality, with the hidden costs, human and environment. Petrol looked at first sight cheap but the true cost of fossil energies is enormous, as we can see now.
    I won't enter in detail but if people think that going from petrol to electricity is the solution, they make a big mistake. Simply it will be impossible in a not so far future to use a big 2 tons car, plenty of steel, alu, plastics and highly polluting batteries for moving the *** of a 200 pounds guy from his house to his job. Maybe he will have to think about a bicycle and sweat a bit. It's just a short example...
    Sadly the most reasonable solution is highly controversial and politic because it is about philosophy of life. How do you want to live? What are your goals?. The basic meaning of life. Fair sharing of the created wealth, frugality, other goals in life than consumerism are a rational solution...But that won't work, so the hard packed solution will come by itself. The whole system will fall down at very high cost, specially for the poor. When? No so far.
    clmanges and bajansailor like this.
  3. LLL003
    Joined: Dec 2019
    Posts: 3
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    Location: Cardiff, Wales

    LLL003 New Member

    Thank you all for the comments, I'd just remembered about this post and figured I'd check on it!

    Gotta dream about something!
    Very valid point, but the car is just for scale, the ramp and forward "cargo" area is mainly for getting bulky/heavy stuff out of the workshop and onto dry land, and vice versa. Looking back though I can see and agree how that solution definitely compromises alot!
    I fully admit, that's probably all wishful thinking, but it would be nice! The preference for Diesel Electric / hybrid probably comes from my background in electrical engineering I'll admit! From looking into what already exists, this does appear to be the way to go in the future however, and it is already used in yachts smaller than this, so while it's expensive at the moment the price will likely fall.
    With the Diesel Electric setup I was basing my rough back of the envelope on using a genset that can provide slightly more than 2hp/ton, and using the stored battery energy for bursts / short journeys above that. That way I can use a much smaller/lighter engine than you'd normally see on a 70', as it only needs to meet the average power demands, with the battery taking up the peak. I'm in no rush to get anywhere particularly fast, so 6 ish kts isn't bad.
    As far as efficiency goes in comparison, i was basing my maths on a normal diesel being sized for 6hp/ton, so if the base load is 2hp/ton cruising, say a 3hp/ton for a little margin, I effectively can use an engine half the size. I don't have a lot of numbers for engine size vs relative efficiency, but from what I have found running an engine half the size at 100% rather than a larger at 50% or less gives you about a 10-15% saving(~30% from one source, not sure on that though!), which makes up for losses in the electrical drive train.
    At the moment, even if this project works out double my back of the envelope cost, assuming it's useful for 15 years it'll be cheaper per sqft than my apartment. Its not even a nice apartment!

    I'm afraid the solution to that one is a bit outside of my wheelhouse, pun intended.

    Thanks all for your thoughts, much appreciated. I might be back in a couple months with some more potentially stupid ideas...
    Dejay and bajansailor like this.
  4. fallguy
    Joined: Dec 2016
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    Location: usa

    fallguy Senior Member

    Cost per foot to build?

    2000x80 -> 160000
    Probably end up more like

    just curious

    my 35' is gonna be about 3500 on a guess
    bajansailor likes this.
  5. Squidly-Diddly
    Joined: Sep 2007
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    Location: SF bay

    Squidly-Diddly Senior Member

    How about a 40' cat instead of 80' mono? In theory, a truck-based RV could be carried on the deck, and roll off using some of the beams, and the boat could then be disassembled and trailered by the truck.
    38' trailerable,containerable,modular Work/Play cat | Boat Design Net https://www.boatdesign.net/gallery/38-trailerable-containerable-modular-work-play-cat.17326/

  6. Dejay
    Joined: Mar 2018
    Posts: 721
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    Location: Europe

    Dejay Senior Newbie

    I love what you're trying to do! The idea of a floating heavy metal machine shop barge somehow has post-apocalyptic appeal to me :) Or as part of a seastead flotilla. Except I am no machinists and wouldn't know what to do with a lathe haha.

    I'm a total novice but I'm pursuing something similar, so allow me to share my thoughts. I'm dreaming of a power trimaran (similar in style to "Ilan Voyager", google it), extremely light weight and entirely solar powered. I've done some calculation and I believe that can work as a kind of small mobile off grid apartment but with some caveats. Like you can only get a cruising speed of 6-8 knots in the summer or in the mediterranian. But even a 5kW generator could provide enough power to move slowly in winter. If you build lightweight it means less power and less building materials so you save money. And if you can live with those limitations this "techno green" concept can work. But you'd need to build with fiberglass and foam core and it would need to be designed and engineered well. I could have a 3D printer and a small composite workshop, but not a mill :)

    Building a blocky barge out of steel is the easiest and cheapest way to build a sturdy hull (I think, again I'm a novice). But I believe it gets expensive because you need a strong engine. If you don't move much maybe that isn't that important and you could get towed. Or maybe in the coming decades we'll see a hydrogen economy with fuel cells to power a ship like that. But steel means heavy and heavy means bigger engines and more fuel consumption if you want to travel around with the boat.

    If you want to live at anchor off a coast you'll want something with kinder motions that a barge I believe. Like a trimaran or a catamaran platform houseboat. Unfortunately you'll loose some space. Then make it 5m wide and less long instead. You'll need to consider windage too. Staying only on protected waters in rivers and lakes would make things much easier.

    So you'll need to consider your requirements, what you want to do with your boat. Like if you want to run a machine shop, who will be your customers?

    Instead of a car, a bicycle or a velomobil or tricycle with pedal assist might be more practical (max 25km/h). There are even amphibian velomobiles! That might be ideal for shopping or exploring.
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