Arrangement for trailerable powerboat ?

Discussion in 'Option One' started by fcfc, Jun 12, 2006.

  1. fcfc
    Joined: Feb 2005
    Posts: 779
    Likes: 29, Points: 28, Legacy Rep: 399
    Location: france,europe

    fcfc Senior Member

    Do someones have ideas for general layout for a trailerable powerboat in the 8' beam with an INBOARD engine with STRAIGHT shaft. The engine would then be a little aft the middle of the boat, and would certainly protrude from the floor.

    Thanks.
     
  2. fcfc
    Joined: Feb 2005
    Posts: 779
    Likes: 29, Points: 28, Legacy Rep: 399
    Location: france,europe

    fcfc Senior Member

    Is there anybody out there ?

    I have refined my own specs

    Trailerable for me so :
    max Beam 2.55 m (8' 4"), strict, not negotiable.
    max weight on trailer 2200 kg (4800 lbs). strict, not negotiable.

    CE design category : B able to survive to wind force of Beaufort force up to 8 (34 - 40 kts) and significant wave heights of up to 4 meter (13 ') for 4 person would be preferable.

    Inboard diesel engine.strict, not negotiable.
    Straigth shaft, power in the 40 - 60 hp range.

    And then some comfort : suitable for a family of 4 for a week : parents and 2 kids. Separate head with shower (so headroom and hot water). Separate sleeping area. 12v electric fridge and microwave oven. Water for 3 days. Black tank and grey tank (3 days too) to allow "restricted area" anchorage. This is minimal comfort, not negotiable.

    And a cruise speed around 11 kts, sustainable for 24 hours on most weather. (about 300 nm range).

    Given the low canoe draft (low weigth) and engine height, the engine box will protrude from the floor.

    Do the shamelessly modified layout from commuter 27 from parker marine or motorlauch 40 from van de stadt are correct tentatives ?

    Are there existing boats with this kind of layout or better , still within what I want (all non negotiable points : size & weigth, comfort, engine type ?

    And how far is this from option One ?
     

    Attached Files:

  3. altura
    Joined: Apr 2007
    Posts: 11
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: usa

    altura Junior Member

    I like it. I would decrease the beam to no wider then 8ft and leangth to 30-32feet.(tight fit into cargo container) and possibly a little taller. Maybe a little more aero dynamic look (modern for resale)

    Change inboard diesel to outboard diesel (maybe yanmar diesel 37hp with a oversized prop) will increase cabin room and other areas etc. limit engine noise and vibration, with such a narrow beam its gona feel really cramped with an inboard right in the middle of the galley. Drive it right up on a sandy beach, really sucks to hit the prop, bent the strut and shaft while loading and unloading from trailer.

    Should cruise at 12+knot non-stop and with a large fuel tank could cross the atlantic. With duel outboard diesels should cuise 18+ and top speed of maybe 20+.

    Now just need a 2axis clamshell rotomachine 10meters x 3 using high density poly and can melt out 20 nearly complete boats per day at $3-4k for hull/cap, now where to find the $300k to start the project? :confused:
     
  4. marshmat
    Joined: Apr 2005
    Posts: 4,127
    Likes: 146, Points: 0, Legacy Rep: 2043
    Location: Ontario

    marshmat Senior Member

    If we are to consider containerable shipping, we are restricted to the standard ISO container's door dimensions of 2338 mm wide by 2583 mm high (approx 7'8" wide by 8'5" high).
    Fcfc, I think you're on a good starting track, at least regarding the size and general layout you're looking at. Just chopping up and rearranging other boats obviously won't work in reality but it gives us an idea what you're thinking of, and I think you've got a good idea what you want already.
    Longer and narrower will be more efficient and faster. But keeping the total weight down under 2.2 tonnes will be difficult.
    If inboard diesel is your powertrain of choice, you'd be wise to consider a skeg to protect that prop. I presume you've ruled out twin-engine configurations?
     
  5. altura
    Joined: Apr 2007
    Posts: 11
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: usa

    altura Junior Member

    I saw somewhere sombody was tilting a 8.2ft+ beam, 34ft long into a container. I may have been one of the taller containers though, id need to check on that one.

    A vessel of this type interests a lot of people i think. I live in california and like to go to catalina for the weekend. In my 26ft bayliner cabin cruiser it costs me about $220+ just to get there and back and cruise around a little bit, forget about even exploring as the cost of fuel would bust you. Going to the river is even worse. The yanmar diesel outboard uses about 1.5 gph, figure you could run the thing at max speed for 10 hours strait for a little over $50 compared to $300.
     
  6. marshmat
    Joined: Apr 2005
    Posts: 4,127
    Likes: 146, Points: 0, Legacy Rep: 2043
    Location: Ontario

    marshmat Senior Member

    A Bayliner 26 is a fat inefficient pig. No offence, altrua, but Bayliner never meant them to be used for long passages. Just like virtually all similar craft, it's built for maximum interior space in a given length when sitting at the dock.
    I agree completely that there's probably a lot of interest in something longer, slimmer, more efficient. A boat like fcfc wants could probably be done such that there's a smooth, clean increase in speed as the boat climbs to a semi-plane state, without the horrific bow-rise and associated massive wake that conventional full-planing cruisers tend to have trouble with. And the smaller engine will be a huge advantage with fuel prices heading the way they are.
     
  7. Geoh
    Joined: Jan 2007
    Posts: 53
    Likes: 1, Points: 0, Legacy Rep: 12
    Location: Arizona

    Geoh Junior Member

    Here is the project boat i am now working on. allweatherboats.com It is 26' by 8' and the extra length would make it usable for 4 people. 29 hp perkins cruises at 7 mph since full displacement hull speed is 6.4 knots you could get more speed with more length and more engine.
    Take a look at the Degero 28 for interior concepts.
     
  8. Geoh
    Joined: Jan 2007
    Posts: 53
    Likes: 1, Points: 0, Legacy Rep: 12
    Location: Arizona

    Geoh Junior Member

    Also go for more hull speed by eleminating the double ender and designing a different stern.
     
  9. Geoh
    Joined: Jan 2007
    Posts: 53
    Likes: 1, Points: 0, Legacy Rep: 12
    Location: Arizona

    Geoh Junior Member

    just noticed date on original post...lol...were about a year late.
     
  10. thudpucker
    Joined: Jul 2007
    Posts: 885
    Likes: 31, Points: 0, Legacy Rep: 453
    Location: Al.

    thudpucker Senior Member

    Now I'm coming in on this another year too late!
    In the old days (days of my youth) there were a heckuva lot of boats just about the design this thread is about, made of wood.
    Awful things to keep up with.

    Most had Inline, small cube engines, right in the middle of the walking room.

    You could take them right up on the beach because they had the big Skeg which protected the prop and rudder and most of the bottom.

    I found out years later why that design. Cheap, efficient, and sturdy.
    The design didn't need a lot of HP.
    In fact you could take out the 25 Hp inline four and replace it with a barnstorming V-8 and still the boat would only make 10 Kts.

    The math was easy. If you had a given distance, 10 Kts was the speed you had to cruise with so computing time, fuel, etc was something you could do in your head.

    fcfc needs to go back in time and find a bunch of article's out of the 20's and 30's and he'll have his boat design.
     
  11. Pericles
    Joined: Sep 2006
    Posts: 1,948
    Likes: 106, Points: 0, Legacy Rep: 1307
    Location: The heights of High Wycombe, not too far from Rive

    Pericles Senior Member

  12. altura
    Joined: Apr 2007
    Posts: 11
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: usa

    altura Junior Member

  13. Pericles
    Joined: Sep 2006
    Posts: 1,948
    Likes: 106, Points: 0, Legacy Rep: 1307
    Location: The heights of High Wycombe, not too far from Rive

    Pericles Senior Member

  14. FAST FRED
    Joined: Oct 2002
    Posts: 4,519
    Likes: 109, Points: 63, Legacy Rep: 1009
    Location: Conn in summers , Ortona FL in winter , with big d

    FAST FRED Senior Member

    If its going to fit in "the Box" a loa of 39 will cost not a bit more to ship, and allow a grand interior.

    The boat with an extra 13 ft of loa will be faster with the same fuel burn and cost only a bit more to build.

    It would still be trailerable , as weight is the limiter for most tow vehicles not length.

    FF
     

  15. thudpucker
    Joined: Jul 2007
    Posts: 885
    Likes: 31, Points: 0, Legacy Rep: 453
    Location: Al.

    thudpucker Senior Member

    39' long and only 7-8' wide?
    Isnt that gonna limit the highth over all to something like 6'?
    A hard top, only four feet off the water does not provide much distanc vision.
    I didnt use any math there, just experience. Long skinny boats tend to roll a good bit.
     
Loading...
Similar Threads
  1. parkland
    Replies:
    18
    Views:
    18,011
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.