Lock Crowther Kraken 25 Trimaran.

Discussion in 'Multihulls' started by oldsailor7, Oct 18, 2010.

  1. kayakayak2004
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    kayakayak2004 Junior Member

    Sounds like a lighter,more efficient mast and curved crossbeams for better wave clearance are two improvements that could be made to the K25. How about a high aspect mainsail?
     
  2. kayakayak2004
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    kayakayak2004 Junior Member

    Oldsailor7. Do the Kraken 25 plans call for the same round mast section (6061T6 alloy) as the Buc 24? How much do you think it would weigh in comparison to a carbon mast?
     
  3. oldsailor7
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    oldsailor7 Senior Member

    Sheet 7 of the plans shows the mast 30ft long, with a single spreader and a
    minimum teardrop cross section of 3 1/2" X 4 1/2", weighing 1.33 lbs/ft. It would have an integral luff groove, or a flat on the back to take a rivetted slide track. You could use a suitable tubular section, with a rivetted on slide track. I would say a min of 4 1/4" dia and the same weight in 6061T6.
    A carbon mast would be much lighter ---but much more expensive.
     
  4. Corley
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    Corley epoxy coated

    You could make all sorts of changes and improvements based on the accrued knowledge of 50 years of multihull development since this boat was drawn but you end up with something other than a kraken 25 C class trimaran.
     
  5. kayakayak2004
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    kayakayak2004 Junior Member

    Yep. You are right. Nothing like the original design. The Kraken 25 looks super from old photos and I'm sure it has a good turn of speed as originally designed. Sticking to the plans is probably better for me in the long run. I just thought I'd add some other ideas for possible improvements since a carbon wing mast had been mentioned. No disrespect intended.
     
  6. Corley
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    Corley epoxy coated

    It's cool I'm not castigating you at all just making an observation and yes I am going to install a carbon mast on my boat so I guess I'm somewhat of a hypocrite myself ;). I'm actually only doing it for the weight saving and the ease of lifting and dropping a carbon mast vs aluminium. My other reason is I've not built a mast before or worked with carbon fibre so it will be an interesting project.

    If you were to make new beams for the boat looking at what samnz did with his beams on his bucc24 might give you some inspiration. If I was to change the beams I'd look at extending them to 18' instead of 14' to give that extra righting moment for a high aspect rig. The beams are a simple faired plywood box beam so recalculating the loadings would not be difficult. If you look at the Victor T vaguely C class trimaran designed by the Gougeons it was a square trimaran at 25' x 25' and they had good results with the format.
     
  7. oldsailor7
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    oldsailor7 Senior Member

    Charles.
    Did you get my PM. :?:
     
  8. kayakayak2004
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    kayakayak2004 Junior Member

    Kracken 25 plans

    OS7. Got your PM. Will send funds soon. Thanks.
     
  9. kayakayak2004
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    kayakayak2004 Junior Member

    Corley. Thanks for the info on Samnz crossbeams. Are there any pics on the Bucc24 forum? What beams I make will need to be demountable. How's your re-build coming?
     
  10. Corley
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    Corley epoxy coated

    http://www.boatdesign.net/forums/multihulls/buccaneer-24-trimaran-25159-11.html

    Theres a bit of discussion on the linked post and some pictures of the beams that samnz put together they look good and were strong enough for a heavier boat.

    My rebuild is going well I've popped a few pictures into my build log thread I have the original floats and crossbeams but lately I've been considering building new floats I think by the time I strip all the paint from the existing floats and remove the deck and epoxy and fillet all of the bulkhead and keelson I might simply be better off building new hulls still tossing up on that one.
     
  11. ian turner
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    ian turner New Member

    oldsailor7

    Like you to contact me Oldsailor7, (07) 47785197. We have just finished the Magnetic Island race week, Yesterday, Sept.6 was last day of racing, in the multihull division, about 7 boats, was easily won by a Nacra 36 with blistering performance. Of interest was eDoc (Top Gun) also very fast but capsized in the last race, mast held the boat from inverting 180 deg. in about 10m of water, rescue boat righted eDoc about 1 hour after capsice, after dropping sails she powered under he own steam back to marina, central pod and motor didnt even get wet.
    Regards Ian
     
  12. oldsailor7
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    oldsailor7 Senior Member

    Thanks Ian.
    It was nice to make contact with you after all these years.
    I still have, sitting over my computer desk, a large print of you sailing the Crowther Typhoon wing mast cat with which you blew away the competition in Florida back in the day. :D
     
  13. oldsailor7
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    oldsailor7 Senior Member

    I have egg on my face because of my posts #69 & 71. When going thru some archives last weekend I came across a graph showing Crowther plan sales for the year 1976/7. In the graph it clearly shows that we sold four sets of the Kraken 18 off the beach trimaran. So the Kraken 18 did exist after all.
    In the same time frame we sold one Kraken 25 set, two Bunyip 20 sets and seventeen Buccaneer 24 sets.
    That tells a story doesn't it. :eek:
     
  14. Corley
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    Corley epoxy coated


  15. Silver Raven
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    Silver Raven Senior Member

    G'day "old-fella" with great respect. I sailed a Crowther B class cat - Mystrey
    c/w 128sq ft wing mast back in the olden days. Can't find a pic of it. Might you have one? Spent many a fun weekend sailing with & against Lokie & Beryl on Botany Bay way back then (geese she was a great sailor - for sure) Some chaps in 'Boat-design' were asking me for a pic & I can't find the book it's in. Any help would be appreciated. That wing designed & build by Brian Leverton was & still is way ahead of its time - big - light- strong - very efficient & more than a hand-full at times - for sure. Ciao, james
     
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