Recently purchased our first boat - 1984 45' Catamaran

Discussion in 'Multihulls' started by Moshe Chocron, Jul 17, 2021.

  1. Moshe Chocron
    Joined: Jul 2021
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    Location: Israel

    Moshe Chocron New Member

    Hello all,

    My wife and me recently purchased our first boat and working on the plans to make our dreams to live and world travel come true :)

    Some local "experts" expressed their concerns on the design of the boat and its ability to handle oceans travels.

    Attached are the boat design schematics (the originals ;-) and they match the builtup.

    We would love to hear this forum experts thoughts, especially as we do not fully trust the opinions and remarks on the design of the boat as the local "experts" did not convince us they are really experts :)

    The boat was purchased from the person who ordered it to be built it years ago, and over the years he never traveled it but near shore trips due to an unfortunate accident that crippled him years ago......

    This forum is amazing and we love it!!

    Thank you all!

    <mod note: welcome to the forum; thread title updated for clarity>
     

    Attached Files:

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  2. bajansailor
    Joined: Oct 2007
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    Location: Barbados

    bajansailor Marine Surveyor

    Welcome to the Forum Moshe.

    The title of your thread is a bit mis-leading - your boat is 45', not 84' long.
    She is an old design, probably from the 60's - her designer appears to have been influenced a bit by the 30' Oceanic cat, and yours looks like a larger version.
    Was she built in England, or in Israel?
    Many Oceanic cats have successfully crossed oceans, and I think that some have been around the world.
    But what is more important re your boat is the condition of it - did you have a survey carried out on it before you bought it?
    Dare I ask how much you bought the boat for?
     
  3. Moshe Chocron
    Joined: Jul 2021
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    Location: Israel

    Moshe Chocron New Member

    First, I thank you for your answer.

    And yes, it is 45" long and I meant it was built in the year 84.

    With the little information I could get, it was built in Israel with the supervision of people that were brought from England.

    We actually bought it for a "cosmetic" cost from the owner ( we discovered strong bonding connection between us of events years ago ;-) This what lead eventually to us being the owners as we actually did not plan for it although we had dreamt on it :)

    As for the boat condition - the boat successfuly passed over the years Israel's boat licensing tests that occur each two years, and as we got it we had replaced the engines oils and sailed it successfuly for 200Km to its current docking marine without a problem ( we used engines as the sails were removed years ago ).

    We appreciate the information you gave us on the design - our major worry from the local "experts" is their in one hand bad wording the design and the other trying to convince us to sell it to them ha ha

    What is your recommendation for us as first steps?
     
  4. Mr Efficiency
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    Mr Efficiency Senior Member

    What specifically was the "bad wording" of the boat to do with ? What particular shortcoming did they see ?
     
  5. Moshe Chocron
    Joined: Jul 2021
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    Location: Israel

    Moshe Chocron New Member

    Thank you for the reply

    Most of their complaints are practicly on general on catamarans:
    dont get it far from shore since "catamaran break in half" - this we already saw is a myth in the internet :)

    On this perticular design they say "it is too close to the water by design" so it can not sail in high seas. This we do not have the knowledge to determine. I can tell you that the design indeed matching the current built up ( we did the measurements and they seem fitting the designs ).

    Is there a minimum height above water a catamaran should be? on its lowest part, our catamaran is indeed only 45 cm above the water..... ( I mean the lowest height of the tunnel that is above the water between the two hulls).
     
  6. Mr Efficiency
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    Mr Efficiency Senior Member

    That 45cm is quite low. You can probably find a formula on the net, or someone here will know it, for the minimum advisable clearance, but I would say for a boat that size 60cm would be marginal. The hulls themselves are pretty low-profile, perhaps designed from the Med ? Although no doubt it is little different at times to the open ocean in the wider expanses
     
  7. Moshe Chocron
    Joined: Jul 2021
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    Location: Israel

    Moshe Chocron New Member

    much appreciate your thoughts.

    is it possible to raise a boat height, or it is considered to be "non possible"?

    or maybe it is simply "over weighted" now? we did loaded it with things....

    how do i know how much weight i can load on my boat?

     
  8. Mr Efficiency
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    Mr Efficiency Senior Member

    When you say loaded it, with permanent increased weight ? There is no easy way to gain clearance, other than a lighter boat
     
  9. Russell Brown
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    Location: washington state

    Russell Brown Senior Member

    With some boats it's pretty easy to make them lighter, just remove everything that isn't useful. Lightening the boat will make it safer and faster as well. How much unused stuff is on the boat? What materials is the boat built from?
     
  10. bajansailor
    Joined: Oct 2007
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    Location: Barbados

    bajansailor Marine Surveyor

    Moshe, do you have some jpg photos of your catamaran please?
    You are probably not yet allowed to post photos, as you only joined today.
    But if you have a nice selection of photos, you are welcome to email them to me, and I will post them for you.
    My email address is tinsmyth@gmail.com

    One of the drawings that you posted notes that the construction is 'cold moulded strip veneer planking over pre-fabricated laminated frames with final cladding of glassfibre or nylon sheathing'.
    If you have any photos that show construction details, it would be nice if these could be posted as well?

    Do you know what type of timber was used for the construction, and if the cladding was fibreglass or nylon?
    You note that she was built in 1984 - they might have used nylon still then, but if it was fibreglass sheathing, I would hope that they used epoxy, rather than polyester resin.
    Do you know what type was used?

    Re the two inboard engines, I presume that they are diesels - what make are they and how much power?

    If I scale off the end elevation drawing, I get the clearance of the underside of the bridge deck to be about 57 cm for the waterline at the 3' draft as shown - but I think that this is probably rather optimistic even in the lightship condition. Your draft is about 12 cm / 5" more than this, re your quoted clearance of 45 cm.

    How much sailing have you done in the past, and on what types of boats?
    You mention that you want to travel the world now, ideally with this boat - you really do need a fair amount of experience first in sailing before you venture across oceans, and also you need to spend time getting to know your boat, and all of her foibles and idiosyncrasies.
    I presume that you intend to buy some new sails for her?
     
    Last edited: Jul 17, 2021
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  11. Rumars
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    Rumars Senior Member

    The design is old, it has a solid foredeck and not a lot of bridgedeck clearence. This means the boat will be more prone to slamming in certain sea conditions then more modern designs. This does not mean it's unsafe, it means it's just a fact to be aware of, and take appropriate action (slow down, sail a different angle if possible).

    Somewhere in those plans there will be some displacement numbers, hopefully for different load conditions. Next time you haul out, you weigh the boat and compare the result to the official numbers, that tells you how much you can carry. If you want to loose weight, there are a few things possible. Besides looking at every loose item on the boat and asking yourself "do I need it", and if yes "how can I make it lighter" (cut the handle from your toothbrush), there are more radical and expensive options. Modern engines and lithium batteries are lighter then the original equipment, watermakers remove the need for big watertanks, good sails mean you need to carry less diesel. Then you can go after the interior, remove all wooden trim, doors, drawers and other unnecessary furniture, then bore holes in the remaining structure.
    How far you take this is your choice, there is no rule.
     
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  12. fallguy
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    fallguy Senior Member

    A 5% bdeck clearance is about the minimum to avoid slamming.

    2.25 feet or 68.5 cm is 5%

    6% is better or 2.7 feet or 83 cm

    so, you are low and will have to choose your crossings wisely

    oftentimes old boats take on a ton of excess weight; it can be any number of things, but you got a lot of good advice on the weight, only unlikely you are coming up 20 cm

    I think you ought to post some pictures of the vessel and any concerns you may have.

    If you have no rigging, the boat should already be lighter.

    EDIT
    I see the boat is 42' DWL, so 5% is 2.1' or 64cm, so you are 19 cm above a low standard...
     
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