Buccaneer 24 Builders Forum

Discussion in 'Multihulls' started by oldsailor7, Jul 22, 2009.

  1. rcracing2
    Joined: Aug 2010
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    Location: Burdekin, Nth Qld

    rcracing2 Junior Member

    [​IMG]

    Sorry, here is the inside of the beam.
     
  2. Samnz
    Joined: Nov 2008
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    Location: Auckland

    Samnz Senior Member

    if you can find an engineer or designer that would go near this sort of issue without charging more than the boats worth ill give you a bottle of rum.

    Those beams are very very heavily built.

    do not replace them theres about 400 hours work in either method new timber beams or alloy tubes, half the work is cutting the old ones out without butchering the boat to badly.
     
  3. Samnz
    Joined: Nov 2008
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    Location: Auckland

    Samnz Senior Member

    Dont get to overwhelmed by the prospect of repairing them.

    all you need to do is use common sense to make the join the same strength as it used to be without a hard spot.

    try buy some timber the same as the front and back edges of the beam and build a block 300 long that can slide into the hole with a 5mm gap all the way around it, and build it up to the right size with glass unis and double bias and bog.

    Sand the inside of the beam to fresh timber with sandpaper on a stick (double sided tape works well)

    thats the first step then do you want it demountable or not?

    if not its easy, first join it back together, slide the block into the beam with lots of bog around it and inside the beam and butt join the beam (id do a dry run first to check it all lines up and slides in easy)

    then (once the bog is cured) powerplane off 6mm of ply on the top, bottom and sides of the beam around 300mm back from the join, you wont be able to do it on the back face of the front beam or the front face of the rear beam so just leave them as a butt join.

    you'l have to cut away a small area of the cabin and "foredeck" on the front beam, try do it tidily so you can glue it back in place afterwards.

    glue in some 6mm ply in the areas you have powerplaned.

    Put plenty of glass double bias and unis over the join making sure they overlap the 6mm ply strips so as not to create a hard spot.

    Glue and glass back on the bit of cabin and foredeck you had to remove and wallah you have a trimaran again, the join will be stronger than the beam ever was, and wont have a hard spot.

    I suggest you get the thing back in the water as cheaply and quickly as possible and go have some fun!

    You can try talk to an engineer or designer if you like banging your head against brick walls :)
     
  4. oldsailor7
    Joined: May 2008
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    Location: Sydney Australia

    oldsailor7 Senior Member

    I would consider butt gluing the beams back together using epoxy glue, and then glue and throughbolt suitable length SS metal plates top and bottom across the join.
    Problem is ---there does not appear to be enough room to do this on the top inboard end of the front beam. :(

    The advantage is, since the water stays are still there, the beams will be in compression most of the time and supported by the main shrouds
    when the windward float is in the air.

    My Piver Nugget had solid 4" x 4" beams and no water stays. The beams were saw cut outboard of the cabin sides. The beams were held together by a galvanized gate hinge on the top and two pieces of angle iron butted and bolted together on the bottom. For storage and trailing the clamp bolts underneath were relased and the floats could be folded up onto the cabin top and be lashed together for security. That system worked fine and was trouble free for the four years of hard use that we had the boat.
     
  5. bruceb
    Joined: Nov 2008
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    Location: atlanta,ga

    bruceb Senior Member

    beam repair

    Does the boat still have its waterstays? If it does, those beams are probably stronger than the alloy tubes and are mostly in compression. B
     
  6. Samnz
    Joined: Nov 2008
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    Location: Auckland

    Samnz Senior Member

    i thought id post these as motivation, get stuck in, dont fret about the details it will come together and be just fine :)

    the last pic you can see a grey patch on the port front beam. I snapped the first rig and it landed on the beam and put a large hole in it. i found a new mast, screwed a bit of wood over the hole and went yachting, repaired the hole properly in the method I suggested you use 6 months (and 15 races) later and its better than new 4 years later.

    I have dealt with many engineers and they just dont like wood. and dont like being held responsible if thier suggestion breaks so wont help in most cases.
     

    Attached Files:

  7. oldsailor7
    Joined: May 2008
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    Location: Sydney Australia

    oldsailor7 Senior Member

    Sam --Thats a great shot of Capricorn flying the "Black Assy" :D
     
  8. Samnz
    Joined: Nov 2008
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    Location: Auckland

    Samnz Senior Member

    thanks, can you see the repair on the beam?
     
  9. oldsailor7
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    oldsailor7 Senior Member

    Sure can . Thats a BIG patch. :eek:
     
  10. bruceb
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    Location: atlanta,ga

    bruceb Senior Member

    Good advice

    Nice pics, thanks for posting them. B
     
  11. rcracing2
    Joined: Aug 2010
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    Location: Burdekin, Nth Qld

    rcracing2 Junior Member

    thanks for all your replies and for all the knowledge that you have shared. Fruit Bat is a great little boat and i cant wait to get back out there on her. Stupidest thing i ever did with that boat was in a westerly on lake macquarie with the masthead assy in about 25knots. All good fun though. I'm still a couple of months away from actually getting it back together but the anticipation is growing, especially now i can see a light at the end of the tunnel.
    Great pics by the way.
     
  12. robjgould
    Joined: May 2010
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    robjgould Junior Member

    The waterstays change the whole game plan - happily. One option is to plug the beam ends with a 150mm protrusion, and apply reinforcing epoxy/glass sheathing wound round the existing cut ends. This would reduce the risk of the existing structure rupturing under load. If silimar sheathing is applied to the hull beam stubs, and their interiors suitably cleaned up and sealed with epoxy, then it is possible to retain a demountable beam connection. The beams can be inserted into the hull stub ends, held in place with a couple of s/s bolts (suggest horizontal through middle of stubs - i.e. the neutral axis) and the boat rigged as usual. A similar arrangment at the float ends would allow the boat to be dissasembled when required - a very usefull feature.

    Cheers

    Rob
     
  13. rcracing2
    Joined: Aug 2010
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    Location: Burdekin, Nth Qld

    rcracing2 Junior Member

    That sounds like an excellent way of going about it Rob. Being able to dismantle it would make it easier for maintenance as i'd be able to the whole thing back to the farm if needed. It wasnt a priority to have dismantle but if it can be acheived effectively i'll go about it that probably,

    Cheers,

    Robert
     
  14. rcracing2
    Joined: Aug 2010
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    Location: Burdekin, Nth Qld

    rcracing2 Junior Member

    waterstays

    [​IMG]
    While ive got everyones attention with the beams ive got another problem. It has to do with the waterstays penetrating the hull and keeping it watertight. When the boat was sitting on its mooring i had endless trouble with water getting in through the bracket for the waterstay. It was waves that caused the problem by moving the amas up and down by small amounts but allowing enough movement for water to get in. I slowed the problem down by running my spin halyards to the amas just in front of the forward beam and pulling them super tight. It will be on a trailer, not permanently in the water when i get it back together this time and im thinking that i might make up some 'boots' out of some scrap PVC cloth and siliconing it to the hull and waterstays and also getting more pressure on the forward waterstay. It was always loose before. Just interested if anyone else has had this issue and ways to correct it,

    Cheers,

    Robert
     

  15. robjgould
    Joined: May 2010
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    Location: UNITED KINGDOM

    robjgould Junior Member

    Hi, just had a quick bash on the PC and the attached is a graphic example of my previous post regarding demountable joints. Sorry for the basic drawing style but it's pointless modelling any detail if the arrangement isn't appropriate etc.

    Cheers

    Rob
     

    Attached Files:

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