Mast Raising

Discussion in 'Multihulls' started by oscarvan, Jun 13, 2009.

  1. oscarvan
    Joined: May 2009
    Posts: 18
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    Location: Bethlehem, PA

    oscarvan Junior Member

    I am getting closer....... now working on a mast raising setup. On the trailer, ama's folded. It needs two things, a fulcrum and stabilization. Because of the mast foot design it needs to come up from forward to aft. There's a nice support on the post on the trailer that will support it laying clear of the bow pulpit, with the bottom of the mast in the foot, hinge pin installed. (It gets removed afterwards as it is a pivoting mast).

    I am using the boom as a fulcrum, with the halyard to the end and the main sheet as purchase. It needs side to side stabilization. Also the mast on it's way up needs side to side stabilization. The key is that these stabilizing lines (steel wires with thimbles and snap shackles) attach to a point in line and in plane square to the pivot at the bottom of the mast. This ensures that the required length stays the same on the way up.

    Now, the problem is that this point is well above the cabin top, and that mounting anything there, like a chain plate would require drilling holes, and more importantly, would leave a trip or stabbing hazard on deck. So, I came up with the idea to have a steel ring there, which is held by two wire lines that go to existing mounting points on the floats.

    The way I see this, these multiple triangles keep each other in tension all the way up. It would take seconds to install and remove. Once the mast is up, the forward shrouds tension, as well as the headstay. The halyard/boom/sheet would tie it down until I get the running backs on and voila...... I think this should work, unless I'm missing something. Any comments?

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  2. bill broome
    Joined: Jul 2008
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    Location: sydney

    bill broome Senior Member

    have you considered welding/fabricating a cross bar to the foot of the mast, creating a transverse pivot line? no ******** stays needed. big time saver, on a trailer sailer.
     
  3. oscarvan
    Joined: May 2009
    Posts: 18
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    Location: Bethlehem, PA

    oscarvan Junior Member

    I have considered that. The mast is a rotating mast......(while sailing). That would get interesting, it would have to be removable, and then you're back to setup break down. These two "spiders" attach to existing rings/eyes etc.
     

  4. bruceb
    Joined: Nov 2008
    Posts: 1,223
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    Location: atlanta,ga

    bruceb Senior Member

    raise the mast

    Oscarvan, I built several similar set-ups for boats up to 25', and they all worked just fine. I even had a couple boats set up to do it in the water, although they took some extra effort. The weight of the mast extending past the fulcrum is usually the limiting factor, pinning the step can take quite a bit of strength. The main sheet might have to be extra long, or a different block and line used, I found a 4 to 1 was plenty on 50-70lbs masts. Bruce
     
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