Sail area vs tonnage? Also question on sail conversions

Discussion in 'Boat Design' started by ZackT, Oct 29, 2019.

  1. ZackT
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    ZackT Junior Member

    I'm curious about if it would be possible to add a sailing rig to a platform supply vessel or a large flat deck utility barge. Or are there a particular type of ship that's better for converting?
     
  2. ZackT
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    ZackT Junior Member

    Oh and also is there a rule of thumb for sail area vs tonnage?
     
  3. bajansailor
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    bajansailor Marine Surveyor

    Could you elaborate a bit more please Zack re what you have in mind?
    What sort of work do you want to do with this PSV or barge once you put a sailing rig on it?
    Re sail area, two vessels could have the same tonnage, but one might have much better stability than the other, hence it should be better able to stand up to a given sail area than the vessel with less stability.
     
  4. ZackT
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    ZackT Junior Member

    Honestly I'm thinking of what would be 1 something with as much deck space as possible per dollar spent. 2 something stable. I've seen barges online that are for open water so I'm assuming they are stable. 3 has enough sail area to move. Not fast by any means. 6 knots maybe?
    There are the Dutch barges but from what I've read they don't like open water. Utility barges however what would typically be pushed by a tug can have a really wide beam vs it's length so im assuming they do well in open water. I'd love a giant slow but stable liveaboard that's as minimalistic as possible. I've seen open deck barges over 150' and a 80' beam for under 200k for sale. I'm sure id have to put at least that into a conversion. I guess my question is could you sail a utility barge if you wanted to.
     
  5. ZackT
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    ZackT Junior Member

  6. ZackT
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    ZackT Junior Member

    Im more interested in a flat deck barge like i posted. I'm just wondering if I could make it sail
     
  7. bajansailor
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    bajansailor Marine Surveyor

    Ok, we are getting warmer :)
    Do you want to use it commercially, or do you simply want something to live onboard?
    I have seen a couple of traditional Dutch barges (the type is called a tjalk I think), probably around 80 - 100' in length, that have sailed out to the Caribbean and survived to tell the tale, so they must be reasonably seaworthy.
    If you just want something to live onboard you certainly don't need a barge that is 150' long.....
    Yes you could buy an open deck barge for under $200k, but you would then probably have to spend $500k on it to do all the stuff that you want to do - it just does not add up as being realistic / viable, no matter how optimistic you are.
    And it will not be much fun trying to manoeuvre one of these barges, even if you have a big propulsion engine installed - you would probably also need a substantial thruster at the bow as well to help.
    If you want something that will work as a houseboat that can sail, there are thousands of boats out there that will do the job much better than any deck barge conversion.

    Edit - just saw your additional posts above.
    Yes, a barge will sail off the wind if you put some masts and sails on it, but dont expect it to be able to sail to windward, or even on a beam reach.
    Both of the vessels in the links above would absorb $$'s like there is no tomorrow when you start on the re-fit work, and unless you have an unlimited budget, they could easily bankrupt you (as well as being a huge liability in so many other ways as well).
     
  8. ZackT
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    ZackT Junior Member

    It's definitely not a idea I'm stuck on lol. It's something I stumbled across while messing around online . a large vessel of some sort is definitely in my future though.
    With the flat bottomed of the barge if you added substantial bow thrusters you should be able to spin it I would have thought.
     
  9. bajansailor
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    bajansailor Marine Surveyor

    The first thing to do is to establish a Statement of Requirement (SOR) re what you want your vessel to be capable of doing / achieving.
    List as many constraints / desirable features as possible - it is possible that some may be in conflict with each other, but that will get sorted out later.
    And establish what your realistic budget for the project is. This is perhaps the most important factor to consider.
    Post your SOR here, and see what the collective wisdom of the Forum thinks.
     
  10. Dejay
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    Dejay Senior Newbie

    If you want a sailing vessel with lots of deck space I'd look into multihulls like a catamaran. Or a trimaran or proa. I don't think you're realistically going to sail anywhere on a big heavy barge.

    What is it you really want to do and need? And where and when? How much money you plan on sinking into it?
     
  11. ZackT
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    ZackT Junior Member

    My goal isn't necessarily travel but the ability for it to move itself... Even at 3 or 4 knots. My goal would be honestly more of a floating island and a barge is the closest thing to that I believe. 2.5 million maybe I think would be a reasonable starting point. I'd love for it to be something that's at least actively being worked on say in 3 years or less.
     
  12. ZackT
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    ZackT Junior Member

    There are models with twin skegs I've seen I'm sure it would sail like a pig but maybe good enough to avoid relying on a tug for moving it is the goal.
     
  13. bajansailor
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    bajansailor Marine Surveyor

    Ok, so once you have spent US$2,500,000 on outfitting a 150' floating island barge, what are you going to do with it?
    Do you just want to live on it, or maybe have a floating hotel / Air BnB type of establishment?
    If you just want a houseboat, there are so many wonderful houseboats out there that are self propelled, similarly large motor sailer type sailing boats, which you could buy and have a lot of change left over from 2.5 million.
    You should consider the seaworthiness aspect as well - you want a vessel that can get out of a tricky situation under it's own steam. And if you have sails, you want to be able to sail better than 90 degrees to the wind, so that if need be you can sail off a lee shore if you have no motor propulsion (they can break down).
     
  14. ZackT
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    ZackT Junior Member

    Goal is definitely liveaboard.
    I've definitely looked at quite a few sailing ships and it's probably the route I'll go. I don't need the fancy railings and chromed this or that. I've seen quite a few good options for me in more classic styled or older sailboats. I was just curious if a barge wasn't a possibility just off of open space that could be had.
     

  15. gonzo
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    gonzo Senior Member

    If you are OK with following the old sailing routes, it is possible. They were set for downwind sailing. However, if you don't have a powerful enough engine, and get caught by a lee shore, your barge will become a shipwreck.
     
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