Mast raising/lowering question

Discussion in 'Multihulls' started by Skip Johnson, Apr 12, 2024.

  1. Skip Johnson
    Joined: Feb 2021
    Posts: 33
    Likes: 22, Points: 8
    Location: Lake Tenkiller, Ok, usa

    Skip Johnson Junior Member

    I've got a small dilemma, current proa build has two lightweight 21' masts from sectional step tapered flagpole (~20# each). I had lifted them into place and set them in their ground sleeves glassed into the boat a couple of times and it was doable. But add a little 5mm dyneema and trying it with the trailer not hooked up to a relatively stable car isn't possible for an old man.

    Quick and dirty solution (is there any other?) was a 16' stub mast collared at the cockpit coaming and braced at the base in a fixture resting on the berth flat, about 32" bury. Stub mast was prebent by a tornado in 2018, had been used in a couple of previous proas. 2/1 tackle and everything works quite smoothly, no longer fear a little wind.

    The dilemma is the connection from mast to stub mast. Currently there is a hose clamp capturing a loop of 1/8" dacron line that the hook on the tackle engages. There has to be a better way. I'd like something that is easy to engage and disengage. Current thinking is an eye attached to the mast and a weighted hook that would drop out when loosened, perhaps with a tailing string to make it easier to snag when disassembling.

    QBmasts.jpg
     
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  2. rwatson
    Joined: Aug 2007
    Posts: 6,170
    Likes: 498, Points: 83, Legacy Rep: 1749
    Location: Tasmania,Australia

    rwatson Senior Member

    Good invention there.
    My first thought, would be one of those trick knots that comes undone from one direction, even though it can hold tight in the other direction.
    Just add - a really, really long tail that undoes the knot from high up.

    "Quick-release knots are those that you can undo with a simple tug, and the highwayman's hitch is perhaps the most popular one. It looks like a complicated, secure knot when it's tied, but a quick tug and it comes completely undone."

    Edit: Looks like a fascinating project. Have you got any videos , say on Youtube about it ?
     
  3. SolGato
    Joined: May 2019
    Posts: 393
    Likes: 245, Points: 43
    Location: Kauai

    SolGato Senior Member

    First thought that came to mind was a ball and socket system with the socket attached to the mast and the ball on the halyard attached to the stub mast.

    There are two ways I could see it working.

    One would be in conjunction with a length of bungee that the ball is attached to and a tail returning to deck. The bungee gives you a way to keep tension on the connection while you lift and drop both the mast and stub mast into position during stepping and unstepping.

    The second way would be to eliminate the bungee and design a ball and socket system where the ball pops and locks into position so there’s no fear of it falling out.

    With a yank of the halyard/tail it pops in/out of the socket.

    The socket would be slotted so you can feed the halyard and tail through it.

    One example of a similar system is like that which is used on sun shades:

    upload_2024-4-12_18-27-15.jpeg
     
    Last edited: Apr 13, 2024
  4. Skip Johnson
    Joined: Feb 2021
    Posts: 33
    Likes: 22, Points: 8
    Location: Lake Tenkiller, Ok, usa

    Skip Johnson Junior Member

    Sorry no videos yet, boat's not yet in the water. There is a bit about the boat here page-240#post-952434 based on a bit in Proafile.
    One of my neighbors is a professional photographer with a commercial drone, hope to have some videos once things are sorted out.
     
  5. Robert Biegler
    Joined: Jun 2017
    Posts: 178
    Likes: 95, Points: 38
    Location: Trondheim

    Robert Biegler Senior Member

    Tie a line to your stub mast halyard, around a mast, and back to your stub mast halyard. Attach the bitter end of your stub mast halyard near the foot of a mast. The loop prevents the mast falling away from the halyard, while the bit attached near the foot takes loads parallel to the long axis of the mast. Raise the mast, lower the stub mast halyard, letting the loop slide down the mast, untie loop and bitter end.

    To lower, tie the loop around the mast, the bitter end near the foot. Slide the loop up until the bitter end takes the vertical loads, lift out the mast.
     

  6. Skip Johnson
    Joined: Feb 2021
    Posts: 33
    Likes: 22, Points: 8
    Location: Lake Tenkiller, Ok, usa

    Skip Johnson Junior Member

    A variation of your suggestion works quite well. I just rigged a loop around the mast attached to the stub mast halyard and slid it up to where it snagged on the hose clamp around the mast (the hose clamp has a large thumb screw built in). Based on the initial trial, I will probably lower the "snag point" on the mast a couple of feet to be closer to the CG of the mast, I've ordered some pad eyes for this and some other attachment points on the boat.
    One of the criteria for the design is that it must be easy to rig single handed. The stub mast adds a bit of complication but I can still mount and dismount the masts with the continuous for and aft stays in place.
     
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