Composite multi-chine 38-40 feet sailboat plans

Discussion in 'Boat Design' started by Stefano Dilena, Feb 2, 2022.

  1. Stefano Dilena
    Joined: May 2021
    Posts: 36
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    Location: Slovenia

    Stefano Dilena Junior Member

    Hello Forum'ers!
    I have been studying recent design developments of fast cruising and racing monohulls
    In specific I am talking about features such as:
    - Wide stern section
    - Delta shape
    - Inverted bows

    All these characteristics can be seen in the class 40 boats such as the Mark Lombard Lift ( V1 & V2).
    https://marclombard.com/classe-40-new-design/?lang=en
    and are perfectly applied to fast cruising A-Class yachts such as the RM 1180
    https://www.rm-yachts.com/en/rm-1180-en/

    These characteristics make not only for a fast boat, but also for an easier construction due to the hard chines, a more comfortable sailing due to the wide space on deck, and more space under the deck due to the more volume.
    RM yachts take it a step further and build Ocean-A class certified yachts made exclusively of Plywood/epoxy and multi-chines hull!

    Now the questions:
    - Does such a boat exists for DIY building? Are there any plans available for self construction of a fast / class 40 style boat that can be customised for cruising?

    - If no plans exist as yet, would anyone be interested in developing a kit that is exclusively flat panels and hard chines for an easy construction ( plywood or pre laminated panels).
    I would think of something like thicker than usual hulls and minimal stringers/reinforcements, for a fast construction and a safer boat at the same time.
    In this second case - my part of the deal would be building the first boat!!

    If you want to discuss more the second option you can contact me in private!
     
  2. gonzo
    Joined: Aug 2002
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    Location: Milwaukee, WI

    gonzo Senior Member

    An inverted bow has no real effect on the boat's speed. They are an element of style
    Wide boats don't necessarily make for more comfortable sailing. That depends on many factors.
    Delta shape hulls are another element of the design that can make a boat faster, but only of the rest of the design accommodates it.
    I looked at the website for RM yachts. They show a photo of the boat sailing in in a breeze with seas of maybe 2 feet. The bow wave is already at deck height. In any weather, that boat will be shipping green water over the deck.
     
    Gvidon and rangebowdrie like this.
  3. Rumars
    Joined: Mar 2013
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    Location: Germany

    Rumars Senior Member

    Yes they are available. Examples:

    https://www.fr-lucas.com/-1642 (cruiser/racer, wrc strip plank or foam core)
    https://www.fr-lucas.com/-1656 (racer, wrc strip plank or foam core)
    http://balta.fr/Classe 40.html (racer, wrc strip plank or foam core)
    Balta Patrick Architecte naval, architecture navale, Motor yacht, yacht design, catamaran http://balta.fr/enfant%20perdu%20bermudien.html (cruiser, spruce strip plank or plywood multichine)
    Balta Patrick Architecte naval, architecture navale, Motor yacht, yacht design, catamaran http://balta.fr/D40.html (cruiser, plywood multichine)
    Sailboat-LNM https://www.lnm-boats.com/sailboat-lnm (several racers and cruisers, plywood multichine)
    https://rolland-archi.com/spip.php?article324 (Cruiser, plywood multichine)
    https://sailscow.com/ (plywood/balsa multichine, kit for the 37, 42 version announced)
     
  4. Stefano Dilena
    Joined: May 2021
    Posts: 36
    Likes: 3, Points: 8
    Location: Slovenia

    Stefano Dilena Junior Member

    Of all the links this is the one getting closer to my immagination!
     
  5. Rumars
    Joined: Mar 2013
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    Location: Germany

    Rumars Senior Member

    One more thing, as long as you are prepared to pay for a custom design you can ask any NA you like. If you like Lombard designs just ask the man how much it costs. All that can happen is that he does not have time, or he is to expensive. Any round bilge boat can be reworked for flat panel construction, inverted bow, different cabin, etc. This might (not necessarily) be cheaper then a fully new design, again you have to ask.
    The sailscow is a Plessis design, here is his other work https://www.gplessis-yachtdesign.com/sail
     
  6. tane
    Joined: Apr 2015
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    Location: austria

    tane Junior Member

  7. tane
    Joined: Apr 2015
    Posts: 93
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    Location: austria

    tane Junior Member

    & I am also pretty sure, that, as boat size increases, the advantage of sheet-plywood construction, be it timber-chine or laminated chine, diminishes (sharply above 40'), as the proportion of labour of hull:fitout moves further & further towards fitout. To illustrate with extremes: a chine- daysailer has hardly any fitout -time advantage of the laminated chine(s) over the beveled chine logs (time 60:40=hullpainting, rigg, "internals". 40' "blue-water"-cruising boat: 15:85=hull:all-the-huge-rest, systems,...). Even on the daysailer the laminated chine will not be so much a saving in time, as a saving in skill level required over the beveling of chine logs. (& if you think of a 38-40' self build - the skill level required for a half-way decent fitout will far surpass the skill level required for the beveling of 4 chine logs & a keel.) The main advantage I see with laminated chines is, if the designer provides files for cnc routing of the developped hull panels & maybe of many parts of the interior too, which I guess would be difficult/useless with a chine-log construction. If the desiner does NOT provide the developped hull panels (computer files or offsets), the laminated chine would make things more difficult than a chine log: taking off the outline of a hull panel sure will be easier with chine logs, than none. just my 2 cents....
     

  8. tane
    Joined: Apr 2015
    Posts: 93
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    Location: austria

    tane Junior Member

    a yes:
    @inverted bow: we found a near-vertical (far from "inverted") bow already a major drag when handling the anchor. On an inverted bow you will need an anchorplatform that is projecting quite a bit (or an armour plated bow)
     
    waikikin likes this.
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