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Blocking Plan?

Discussion in 'Yacht Designers Discussion' started by Cthulhu, Jan 26, 2009.

  1. Cthulhu

    Cthulhu New Member

    Joined:
    Oct 29, 2008
    Messages:
    15
    Location:
    Charleston,SC
    I am the captain of a 70 year old motoryacht, and am looking for a bit of advice.

    The vessel currently has no plans to speak of, save a very rudimentary non-scale line drawing that shows a basic break-down of compartments & built-in furniture.

    As we prepare to be hauled out for a USCG inspection, the nearest yard with a synchrolift is requiring a blocking plan, so they can make a docking plan--or do I have that turned around?

    My question is, how feasible is it to reverse-engineer plans for a vessel, and what kind of cost can the owner expect to incur?

    I would love to hear from anyone who knows more about marine construction and design than I do.
    Thanks in adance.
  2. SeaEric

    SeaEric YF Historian

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    Location:
    out on the dock
    Is this a wood yacht? If so, take it to a yard that knows what they're doing. If this yacht has been around the east coast for a while, someone has hauled her in the past and likely has photos or drawings of how to haul and where to block. What size is she? More info would be helpful.

    Or, just take her to Jim Moores. He'll know what to do.
  3. m2m

    m2m Senior Member

    Joined:
    Dec 8, 2006
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    Location:
    newport ri
    In a previous life I ran a marine railway and hauled many boats with no docking plan. I devised an L-shaped device to measure for blocking. I used aluminum angle iron (for stiffness). The measuring stick had to be a little more than half the width of the boat and deep enough to reach the max draft of the vessel (think carpenters square). Place the device in the water and locate the bottom of the keel and take a measurement at the water, next pull the device back and follow the contours of the hull usually about 5-6 feet away from the keel and take another measurement the difference is your side block hieght, You will need to know the measurements between the syncrolifts side blocks so that you know where to take the measurements (this is usually 10-12 feet apart) Try to land on as many bulkheads as possible. If your in the warmer climes a diver is helpful. As stated above if you can find out where it was last hauled they should have measurements or
    photos. Good luck!
  4. Cthulhu

    Cthulhu New Member

    Joined:
    Oct 29, 2008
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    15
    Location:
    Charleston,SC
    Thanks for the response.

    Sadly, the closest place seems to be a very mega-yachty place. I have sent them photos from two previous haul outs (so far, no one at either yard has gotten back to me about obtaining copies of the blocking plans) and that was not good enough for them.

    I suspect that this is not a question of ability on the part of the yard, but rather one of liability. If we have a marine engineer involved, then the yard as someone to counter sue if they damage our boat.

    Having been with the boat eight years and seeing her out of the water thrice, am sure that I can tell the yard where the bulkheads, thru-hulls, &tc are, but as for the angle of my bilges and the sheer of the keel, I am at a loss.

    If I take her to NC where we've been hauled before, maybe I can sweet-talk an architect into measuring her scantlings. I've heard that many of the angles can be reverse-measured using a surveyer's transit and some math.
  5. K1W1

    K1W1 Senior Member

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    Hi,

    Surely if you have been on that boat 8 yrs and seen it out of the water three times then you should have some knowledge and or contacts of where it was hauled before.

    Why can't you go back to one of the places where she was hauled before?

    If it is that old it is a classic and as such maybe there are some plans around for it.

    If you post some more info maybe one of the other members of YF can answer your questions.
  6. Cthulhu

    Cthulhu New Member

    Joined:
    Oct 29, 2008
    Messages:
    15
    Location:
    Charleston,SC
    K1W1:

    Regarding revisiting the yard(s), one is in Wisconsin, which is too far, another in FL, which is a long haul, especially since she has to take passengers to help pay her way. The third is in SC, four days inland run, or one 24 hour steam outside.

    The boat is a 90' long, 18' beam houseboat designed by John Trumpy and built by Mathis in 1939. We have five watertight bulkheads, as we have a COI that allows carriage of 60 people on a protected route. We are docked in Charleston, SC.

    The yard in WI will not release info to me b/c it belongs to the former owner, and he hasn't called them to say it's OK (it probably is, but he's too busy with his Alden schooner), and the yard in FL has never returned my calls. No one in the immediate area (i.e. within a half-day's travel) can or will haul the boat. One local yard has a large enough travel lift but not enough straps.

    The previous owner had no plans, and the man before him mentioned something once about "$200,00 plans" he paid for, but I've never seen them or heard more than that, and they certainly did not come with the boat. One rumour is that John Trumpy burned many of his old drawings so that no one could ever replicate what he had built. This boat being a Mathis, I wonder who had the originals.

    As for hauling the boat, I have photos and memories, so I could probably explain to a yard foreman how to haul the boat. The question is whether s/he will listen to a 30 something captain.

    What I'm really looking for is recommendations on how to measure a boat in the water, or reasonable architects for when she comes out, be it in GA, NC, or RI.

    As we've never had plans, I do not know how much the boat should pay for a set. That's the question I really have.