6.5 to 7.5 metre performance/cruise multihulls

Discussion in 'Multihulls' started by Gary Baigent, Feb 27, 2015.

  1. Gary Baigent
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    Gary Baigent Senior Member

    Ha. Unfortunately they've flown back to 'straya. But you're right about the filming expertise; their father has his own movie business but it's in animation (Tui Studios, Kiwi in Os stuff, eh! Sorry, explanation: Tui is Maori name for a beautiful NZ songbird) - but you're right about the arty farty ability being in the family. However my stuff is heavy reality and not fantasy, like my boat designs. Just joking.
    Another shot; set up the beam box and hatchway.
     

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  2. HASYB
    Joined: Jun 2011
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    HASYB Senior Member

    Birds of a feather aye.
    Sorry for you to hear they've already flown back, guess you don't get to see the Tui turned Kiwi's that often.

    On the other end, quand je n'embarrassez pas, its kind of reassuring to hear looney tunes also run in your family.
    I'm still recovering, if I ever come over that untimely happening, from the last and only time I took the family out sailing.

    Observant readers may also have noticed, despite the apparent distractions, my nonchalant determination in safely navigating trough life and this case Dutch waterways in particular.
     

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  3. Gary Baigent
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    Gary Baigent Senior Member

    Your well balanced lot would fit in perfectly and seamlessly here?
    Rough checking the 650's box beam; think I'll crank it forward immediately it leaves main hull deck; if I continue it out further, as shown, before raking forward, may look too strange, like a broken leg? And this strange foiler is going to be strange enough.
    Anyway instead of working on the 650 (Triumph Bonneville?) I'm off to an afternoon and evening (and most probably late into the night) party of rotten old Kiwi and Aussie raving farters ... who should know better ... but it's too late to change?
     

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    Last edited: Jan 31, 2016
  4. HASYB
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    HASYB Senior Member

    Really not sure if the lot would fit in, not necessarily I guess, this picture was taken during coffee time:roll eyes:

    Still having difficulty to see how the end result is going to be and who am I to question but you have a specific reason to make the box beam so narrow on the hull?
    Wouldn't it make the structure more weak at a point where lots of forces come together?
    Or am I seeing, imagining, things wrongly; seeing bears on the road? (translated Dutch proverb)

    Raving farthers blowing in the wind? Have fun!

    "…but it's too late to change?"
    I guess it's never to late to learn until its too late to change and even then you won't know until you learned to change and/or changed to learn, or is it?
     
  5. Gary Baigent
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    Gary Baigent Senior Member

    Actually thought I was being conservative; the box beam is rather big compared to Sid's: the 650 is 200 x 250mm height/beam - and then the aerodynamic sections go on fore and aft- so it ends up a pretty large beam. Sid's is 250mm height, bit narrower in box beam, see image. Also Sid's overall beam is 8m whereas the 650's is going to be around 6.5m.
    ps: I'm writing this with astonishing accuracy considering the amount of high octane Belgian beer I've consumed.
     

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  6. pogo
    Joined: Mar 2010
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    pogo ingenious dilletante

    Leffe ?
    Kasteel ?
    Trappist ?
    11% vol.

    Prost !





    The taste of american beer ?
    Like making love in a canoe ( fuckin' too close to water ).

    pogo
     
  7. Gary Baigent
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    Gary Baigent Senior Member

    Trappist Chimay and Duval - and no headache this morning!
     
  8. pogo
    Joined: Mar 2010
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    pogo ingenious dilletante

    Sure ?
    What about your finger coordination ?

    Cheers ( it's late in the evening here ; drinking gin.....)

    Go, build a boat for all those....

    pogo
     
  9. HASYB
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    HASYB Senior Member

    OK, OK, being on a strict diet of fine wine I've been left with little more than patiently further contemplate and await this birth of a new foiler and its spirited communication.


    Nevertheless,

    Cheers
     
  10. Gary Baigent
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    Gary Baigent Senior Member

    Building box section of the 650's 6.5 metre beam. The final airfoil shape will be pretty much like Sid's beam in cross section shown here. Oh yes, there is slight dihedral each side of the central box ... for aesthetics? The central box remains a box (so to fit the open case on main hull deck) - while the angled forward beam outer sections will be airfoiled.
     

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  11. patzefran
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    patzefran patzefran

    Hi Gary,
    Looks like you cut the aft part of the mainhull or is it a pictural artefact ?
    Did you weighted the mainhull ?
    Patrick
     
  12. Gary Baigent
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    Gary Baigent Senior Member

    Patrick, I think you are mixing up Sid with the 650; Sid has the long and pointed transom whereas the 6.5 has a higher, less angled shape. to gain some miniscule accommodation area.
    I attempted to weigh the new hull but my scales have broken, probably from trying to find the central balance point under the hull; I guess it is around 75 kgs with rudder and daggerboard.
     

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  13. patzefran
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    patzefran patzefran

    75 kg is very light ! My Strike 20 mainhull is around 150 kg.
    But the maximum payload is 300 kg which need adequate scantling !
     

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  14. Gary Baigent
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    Gary Baigent Senior Member

    Neat looking profile of the Strike 20. The large weight difference to my boat comes from the Strike design using thick sheet ply as opposed to my thin tensioned/tortured ply. The latter, because it has to be bent to get its amazing rigidity, (glass/carbon/epoxy added later) has to be around 3-4mm, any thicker and it becomes almost impossible to get a round bilge shape.
    For hard chine, flat sheet construction, the ply has to be thicker ... because flat ply of 3mm on a flat deck would be like walking on a trampoline. If you closed your eyes you wouldn't be able to tell the difference! Thick ply is stiff but it is also heavy.
    Sid's main hull at 8.5 metres length is proportionately lighter, (with similar weight at 75kgs) than the shorter but wider (in hull and deck) of my new 6.5 metre trailerfoiler design.
    Here's the swivelling beam roughly in fore and aft position for trailering. The next two are of beam in place with bearing epoxied in place. Have started cutting out the airfoil section frsme attachments.
     

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    Last edited: Feb 12, 2016

  15. Gary Baigent
    Joined: Jul 2005
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    Gary Baigent Senior Member

    Had to alter the rudder setup because with the beam swung, the lifted T rudder assembly was too high and with float and foil, would foul the beam. You can't remove complete rudder because of the horizontal lifting foil, that is, unless you go for a swim or hoist the main hull up high. So I bit bullet and sawed an open slot in transom and cut away the back end of case, then sealed each side. Now working on the pin system of the thin rectangular box to fix the rudder solid when in place. You can see where I've ground paint away for the pin fixing points. Also fitted the airfoil frames to the beam.
     

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