fast but lightweight cruiser

Discussion in 'Multihulls' started by Gary Baigent, Dec 25, 2013.

  1. HASYB
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    HASYB Senior Member

    After hearing Chris & Henk talking about anchoring Juniper I wondered about making a device for lets say the daggerboard or a special feature to raise at the back of the boat to play the role as the counterbalance for the main wing mast (A conservative one naturellement).
    This al in agreement with Cavalier's last comment of course.
     
  2. HASYB
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    HASYB Senior Member

    Gary, no no, I had no race boat in mind fantasizing. I'm interested in moving trough the water most effortlessly as possible, to disturb water and air as little as possible, blending in, connecting, working with Earth's natural forces like an stealthy prowling indian in a dry forest: with uttermost pace, care, respect & knowledge.

    Some more design parameters: (realizing/fearing (don't want to hijack) I might have only a slightly different interpretation of light weight and fast as opposed to thread-starter.)

    coast-hopping, being able to sail/motor up rivers/canals, trailerable, little draft, single-handed. mostly ply construction, wing mast (a conservative one :)).
    The floats are demountable and can be tied alongside the main hull.
    The rudder and electric motor(small sound isolated generator) are fitted in tubes so they can be raised/lowered and rotated.
    I'll probably go with L-foils today for lift and reduce leeway.

    Scanner and laptop forgot they were supposed to be compatible at the moment so I took some (crappy) pictures.
     

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  3. Gary Baigent
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    Gary Baigent Senior Member

    Woohoo! What a brilliant crazy man you are Hasyb. That is radical. And good luck with the big bearing. :D
    And there are no rules; you can take over this thread, in fact we want differing ideas.
    With the pivoting main beam you could leave the floats attached all the time? If you made greater overall length main beam.
    I wonder if a dagger erected in the stern crossways would do the same job as a wingmast mizzen/ketch. Maybe it would. Neat idea.
    ps: in the top plan view you have "boomerang" horizontal foils, forward and aft ... which confuse me ... but then I'm easily confused. You doing a Doug Lord?:D
     
  4. HASYB
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    HASYB Senior Member

    Hé Thanks Gary, I think...
    The big bearing, yes that scared me also in the beginning until I realized the bearing really doesn't have to be round or even be a bearing. As a matter of fact it would better be octagonal or similar. If you make the fitting? on which the beam rests a trapezium, you only have to lift/lower the beam in the middle/centre a little to be able to turn the construction or lock it turning.
    I thought about leaving the floats attached pivoting the main beam but that would complicate the construction beyond my current interests. The floats would in that configuration have to be able to stay parallel to the main beam, like Randy Smyth's Scizzor. Could be done though, no doubt.
    The "boomerang" foils: Hmmm... never thought of that, might be worth while musing about. Mind you, I respect & like Doug's Idea's about foiling.
    I take full responsibility for your confusion; it's my lack of drawing talent.
    Originally the "boomerangs" were meant to tie the floats to the hull.:cool:

    Wondering about your cruiser:
    You continue follow the foiling path for this one also yes?
    I ask since I am a little intimidated by the apparent grow of forces on structures, even more after watching the last AC. fjjeeeuuw...
    Also you mentioned live-aboard; I mean, you actually plan living on this boat permanently?
     
  5. Gary Baigent
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    Gary Baigent Senior Member

    Nah, not permanently, just like any other cruiser where you can live aboard for periods of time - what I'm meaning is that this is still a small boat at 10 m but trying to fit (everything lightweight and minimalist) to make"reasonable" living accommodation inside. Thinking of a compromise tri/foil assist that is light and fast yet roomy enough to not become claustrophobic - but the cruising concept definitely leaning to the performance size. Actually after all this verbage, just your average multihull really. Changed the stern to be a little finer, put different poetic license bow on.
    I'll post more drawings later.
    Yes, really like your bearing design ... but lifting the whole beam to rotate? Bit tricky - but another of your clever alternative solutions. My thoughts would be to retain the circular and have locking pins and struts for positioning. But that is Sid old school.
    My cruiser is foil assist, not a full flyer - and the fixed foils are no deeper that the base of main hull. The intention to be able to sail (slowly) in shallow waters without grounding. Small floats plus foils also are light constructions ... which is what this simple boat is all about. There will be a central main dagger and the foils are there to solely lift the small float and provide righting moment, not anti-leeway ... although they will do a little of this.
     

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  6. HASYB
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    HASYB Senior Member

    Hey, nice changes, a lot of your perimeters sound familiar but being a bit jealous on your fancy design-program. I couldn't get it working on the mac.
    Verbage? (had to look it up to be honest) average? Yes, very boring & ultra particular mediocrity are the first things slipping in my mind when seeing your boats :roll eyes:

    On the bearing thing: Trickey? think of two tapering forms being pressed into each other, one only has to lift very little to be able to turn the two. Hell, one only has to press a little air between the two and they will turn. When pressed/vacuumed/wedged together they become one and even stronger, locking pins for security only.
    OK, more then enough ramblings of me for the moment. Looking forward to more averageness. HA
    Cheers,
     
  7. Gary Baigent
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    Gary Baigent Senior Member

    Sketching a few ideas.
    If I make the box core, airfoil outer shaped beam angle forward as shown, that means more material, some complexity in building but it clears the cabin space forward for accommodation; however means climbing over the beam from the cockpit and down steps to get inside.
    And if I make the beam straight, it centralises the weight, (which I like) makes for simpler construction (ditto)... but it splits the cabin area in two. Does that matter? No.
    The two masts will have inverted V struts spreading loads and running to the ring frames and flared hull sides; have to live with that interior framing, no other way round it.
    Hull flared gunwhales can be straight, simpler to build less arty stuff.
     

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  8. bruceb
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    bruceb Senior Member

    Kis

    I suspect you won't use the forward cabin very much except for storage and VERY temporary guests- and/or children ;) so keep it as simple as possible, and straight beams are simple.
    Just looking, and certainly not completely understanding the lines, do you think you should want/need more flare forward above the waterline? It seems with the lack of float displacement forward, that the main hull has to provide all the reserve and more flare would be almost "free" volume, and also might make that forward cabin more useable.
    I my limited observations, most tris seem to carry their bow knuckle at or above the water, except when you "stuff it", and then you want all the volume you can get. I keep wondering if a small pram type bow might work better. It would probably be Butt ugly:(, but you are good at making boats pretty. ???

    B
     
  9. Gary Baigent
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    Gary Baigent Senior Member

    Thanks Bruce. Filled out the main hull bow ... a fraction more on your behalf. :D Remember this is foil assist (Doug's term and it seems to have caught on) with foils set just forward of beam/float junction - and the foils help to lift bow. Also the slender curved bow will tend to knife through instead of throwing the bow up and pitching - and if it goes too far down, there is flare further aft. Sid has this and the boat is very stable in waves.
    Agreed, the straight beam is the better answer, people will just have to duck under it to go forward.
     

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  10. redreuben
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    redreuben redreuben

    Gary my biggest issue with small floats with foils is diagonal capsize, particularly over the rear quarters.
    If the boat is not making way and gets caught aback there is nothing there ?
     
  11. bruceb
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    bruceb Senior Member

    Duck!

    I do think I like that better. Duck the beam is sort of a game- you have "crew" that can, and those that can't. :cool:
    B
     

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  12. rberrey
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    rberrey Senior Member

    Why not widen the beam out to 3' or 4' and use T Beam type bulkheads like a Horstman ? The Beams could be used for berths , hull area between the bulkheads for galley , nav station ect.ect.
     
  13. Gary Baigent
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    Gary Baigent Senior Member

    Red, I've been sailing these tri/foil types for a few years, er, decades now, and never had pitchpole or going arse backward problems.
    But I've buried that low wooded Flash Harry when running hard in, for that small 6x6m boat, large wind against tide seas ... up to the mast ... but the T rudder foil design saved my fish fillets, stopped the stern from lifting out.
    And have been caught in irons and sailed backwards in hard wind and wave (Harry was so light the boat wouldn't drive through head to wind position during tacking), sailed backwards at a rate of knots, helm reversed - and although the main hull stern would start acting like a submarine, never looked or felt like the boat was in trouble. Not saying it won't happen though - anything can happen.
    When Paul Ricard first appeared, your question was also raised ... but it never occurred in reality.
     
  14. Gary Baigent
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    Gary Baigent Senior Member

    Couple more sketches. Think I'm moving somewhat closer to the correct design but there will be more changes, for sure.
    That is an alternative beam setup RBerrey, using Horstman's solution ... but I like the simplicity and lighter weight and good load spreading of the box going right through the boat and onto ring frames with reiforcing, just a carryover of small cat configurations I'm used to.
    The dagger board will be set towards one hull side; the asymmetry has no affect on helm from tack to tack, allows more room (although there is quite a lot going on down there in the accommodation area) and the rudder is inverted T ... because such rudders have worked very well for me in the past, stop squatting, also stern lift out in nose down postions at the same time.
     

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    Last edited: Jan 3, 2014

  15. redreuben
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    redreuben redreuben

    Gary I'll take experience over theory any day. It's looking good !

    Looking forward to seeing the accommodation layout !

    Aft double berth version please. :D
     
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