Tornado to performance trimaran conversion

Discussion in 'Multihulls' started by tamkvaitis, Nov 18, 2009.

  1. jamez
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    jamez Senior Member

    hi Chris, would the tornado hulls work with your Cardiff 21 centre hull or are they a bit small? The rig should be about right.
  2. jamez
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    jamez Senior Member

    Further to that, does anyone know what the volume or immersed displacement of a Tornado hull is?
  3. Richard Woods
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    Richard Woods Woods Designs

    Mark did something similar with his Osprey

    only he used a Nacra 5.8 (I think). lengthened the hulls and built his own main hull. Mast is 31ft carbon

    I have raced against him several times, its a quick boat sometimes, sometimes not (no idea why not)

    Years ago when I worked for Derek Kelsall we did the 25ft Typhoon trimaran based on a Tornado. I remember doing the drawings for a foam sandwich mainhull as well as working on the production version. Derek may still have plans for sale.

    Richard Woods of Woods Designs
  4. luckystrike
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    luckystrike Power Kraut

    Hello Tankvaitis,

    yes, your approach is good. For easier shaping make a 4mm plywood pattern of the bow representing the "now bow" and extend it to the forward. Glue this to the bow using epoxy and shape the "new bow" side profile.

    Now you can glue some pieces of styrofoam (polystyrene insualtion foam 30 - 40 kg/m³) onto the patterns and the hull. Use PU lightly foaming construction glue. Now you can shape the new bow. Laminate the glas fabric (a total glass wheight of 600 gr/m² should be enough, lminate at least one of the layers at 45° direction.

    Have fun and good luck. Don't forget to report your experiences here.

    Best Regards, Michel
  5. upchurchmr
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    upchurchmr Senior Member


    I cannot imagine why you would extend Tornado bows for less drag. A Tornado currently will go lots faster than anything you weigh down with a main hull.

    If you want more volume extend the stern, or use the tortured ply hull as an inner skin, cover with foam and glass the exterior. 1" of foam should get a significant increase in displacement, extending the stern a couple of feet will get more and keep the shape that has worked for around 40 years.

    I'll probably start an argument, but I don't think anything modern with a 20' length goes faster than a Tornado .
  6. HASYB
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    HASYB Senior Member

  7. dantnz
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    dantnz Junior Member

    I have one of those, it has been updated over the years to have the latest tornado square top and running gear. Its just a good cheap fun boat, so thanks!

    I think it is suprising just how much volume is in a tornado hull, this is probably why they have been competitive for so long, only recently superceded by the M20s and F20s etc. The Typhoon main hull is very heavy and with flat beams, but it still works.

    I think you are unlikely to make a tornado faster by adding a centre hull and widening, but why not try? You might turn it into a fast single handed racer. Why not use a 3rd tornado hull as the centre hull, use dome dihedral and canted amas and you would effectively be making a tornado with 10 foot wings and double the righting moment. In fact I'm tempted to try it myself.
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