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Davit

Discussion in 'Technical Discussion' started by lawnfan, Jul 2, 2012.

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  1. lawnfan, Jul 2, 2012
    #1
    lawnfan

    lawnfan New Member

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    I have a 1975 Hatteras Yachtfish with a Viking (Marine safety co, not the boat maker) Davit JR 800DC. I need to know how many pounds its rated to lift, and how heavy a tender I can get for it.
  2. Capt J, Jul 3, 2012
    #2
    Capt J

    Capt J Senior Member

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    I would guess 800 lbs......judging by it's model #
  3. dennismc, Jul 3, 2012
    #3
    dennismc

    dennismc Senior Member

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  4. Pascal, Jul 3, 2012
    #4
    Pascal

    Pascal Senior Member

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    Most Davis model numbers are based on capacity, 800lbs is likely what you have

    Most 1510 Hatts (53/58 MY/YF) had 11' whalers as tenders. You can fit up to a 13' tender with minimal overhang.
  5. lawnfan, Jul 3, 2012
    #5
    lawnfan

    lawnfan New Member

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    OK. I understand the logic of the "800". However, won't most inflatable 13' tenders w motor exceed 800 lbs? And secondly, can I reasonably lift a tender weighing something more than 800 lbs? If so, and granted we're out on a limb here, how much more? I'm hoping to get a 9-11 foot inflatable w a console but I'm flexible on motor size/weight.
  6. dennismc, Jul 3, 2012
    #6
    dennismc

    dennismc Senior Member

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    My 13 ft Whaler with 40 hp is 1000 lbs + with fuel etc....do not overload the davit it can cause structural issues on the main boat deck and possible catastrophic damage to those under the unloading process.

    The older whalers were lighter and my old 13 with 25 hp was 700 lbs max
  7. Capt J, Jul 3, 2012
    #7
    Capt J

    Capt J Senior Member

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    An 11foot inflatable with a console or any 11' inflatable has NO room inside because the sponsons/pontoons take up 1/2 the beam......Get a new 11' whaler and just put a few fenders out. The 11' whaler will hold 4 people comfortably, is unsinkable, and will do more than the inflatable can with much less maintanence.......
  8. garyohv, Jul 6, 2012
    #8
    garyohv

    garyohv New Member

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    If you're going to lift 1200 lbs with an 800 lb. hoist...then identify the areas of stress....what's going to bend or break?
    Add bolts to the base with backing plate or beam.
    Upgrade bolts in stress. You can gain 50%.
    Check the allowed load of the wire. Add a block and double-back the cable...gain 100% load but at half speed.
    The arm can be strengthed with metal strips bolted/glued.
    The pole base needs help resisting bending....with fiberglass or metal.
    You could remove your motor first.
  9. Capt J, Jul 7, 2012
    #9
    Capt J

    Capt J Senior Member

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    I wouldn't put anymore than 800lbs on top of an old hatteras aft deck, ever. I don't think it would safely hold more than that, especially after age has set in, and with the way those boats are in a beam or following sea it would upset handling too much.
  10. Capt Ralph, Jul 7, 2012
    #10
    Capt Ralph

    Capt Ralph Senior Member

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    The liability itself requires you do it all correctly. This is not just a few pounds your swinging over peoples heads.
    Stay in specs or;
    Hire an engineer, purchase the correct davit, make proper reinforcements and spend more money.
  11. Yachtjocky, Jul 7, 2012
    #11
    Yachtjocky

    Yachtjocky Senior Member

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    Forest gump

    DO NOT DO ANY OF THE ABOVE.

    The area of stress to be identified is figuring out which are the stupid posts on here and ones that are just taking the P--s.

    Davits are designed and built with a safety factor and once you exceed the maximum designed load you eat into that load factor.

    load factor is safety factor, take that away and you should be thrown into jail or sued for your last dime when the S--t hits the fan.

    Now let me think abut changing some bolts to gain 50% :mad:
  12. Pascal, Jul 7, 2012
    #12
    Pascal

    Pascal Senior Member

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    this has to be one of the scariest post i've seen here!

    are you really suggesting increasing the load by 50% ??