Boat cradle

Discussion in 'Boat Design' started by Littleship, Oct 28, 2010.

  1. Littleship
    Joined: Oct 2010
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    Littleship Junior Member

    Probably a simple matter but one I just cant grasp on how to safely support the boat while its worked on. The boat in question is a coronet seafarer 27, 8.22m length, 3.16m beam with a .91m draft with a 4000kg displacement. I would like to build a cradle for the boat to sit in while it has work done which will safely support it while allowing people in and on it. Something similar to this http://www.boatshop24.com/web/en/wer...=1&lastshow=75 I'm unsure what points of the hull are best to run supports onto and over what length the stand should run. Any thoughts or other idea's would be helpful.
     
  2. PAR
    Joined: Nov 2003
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    PAR Yacht Designer/Builder

    Your boat could be worked on with proper keel blocking and regular boat stands. I'd use several blocks directly under the centerline, then two straight stands on each side, just under then chine in the after 2/3's of the boat. The forward section could use angled stands, a bow stand or both. Depending on what yard she's in, they'll know how to block her up so she doesn't go anywhere. Chain the stands together to prevent movement.

    If you want a cradle, again a 5, 6 or 7 point rig could be made from angle iron or even dimensional lumber. All depends on how much and how long you need this cradle. Generally, a cradle is necessary for long term layup or transport.

    Is there a specific reason you need a cradle?
     
  3. Littleship
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    Littleship Junior Member

    Thanks Par, boat will be in a private yard with engines to be removed and inside tidy up, its a cash / time relationship as to how long and suitable mooring in my area needs to be found and then away it goes. Material available is tube steel (wood for on hull) and skills to construct but were all unsure just what we should be building to hold it steady and at the same time make sure it doesn't damage the hull. Into the mix we are entering cyclone season here and this year they predict up to 6. probably wont happen but something i should consider.
     
  4. PAR
    Joined: Nov 2003
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    PAR Yacht Designer/Builder

    Generally, the weight of the boat should be supported on the centerline and kept from flopping over with supports along the aft portions of the chine and angled props in the forward quarters. This boat doesn't have an especially long over hang at the bow so a single bow support may do the deed just fine. It's one of those things that you just get a feel for on site. As for hurricanes and the like, it doesn't matter if she's on a stands or in a cradle. If a big enough blow comes in, you're just playing with luck. Now that I've said this, I've anchored a few boats to the ground with screw in tie downs and straps during the "season", which hopefully is just about over for us.
     
  5. Littleship
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    Littleship Junior Member

  6. tom28571
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    tom28571 Senior Member

  7. PAR
    Joined: Nov 2003
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    PAR Yacht Designer/Builder

    There are two types: straight(ish) ones used for powerboats and angled ones used in forward sections of bigger powerboats and on sailboats.

    Tom is right, they don't cost much and if you have a substantial project, they're worth the several hundred dollars they may cost. Of course now you have boat stands to store, but they can go to where ever you haul the boat.
     
  8. Littleship
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    Littleship Junior Member

    Thanks for the help on this one. As luck had it the broker ended up throwing me a cradle for free so its all good.That being said i did come across a lot of the same question regarding a cradle and since this one covers up to 30ft almost a one size fits all option i'll draw it and post the dimensions.
     

  9. PAR
    Joined: Nov 2003
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    PAR Yacht Designer/Builder

    There's no such thing as one size fits all with a cradle, so the broker may not be doing you a favor after all. He may be just trying to unload a piece of junk that's taking up space on the lot. All cradles have to be "fitted" to the boat.
     
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