Headstay attachment on rotating mast?

Discussion in 'Multihulls' started by henrikb, Feb 26, 2007.

  1. henrikb
    Joined: Jul 2002
    Posts: 112
    Likes: 7, Points: 0, Legacy Rep: 116
    Location: Sweden

    henrikb Senior Member

    Do anyone out there have some pictures of how the headstay attachment to a rotating mast use to be designed?
    Any info is appreciated!
     
  2. tspeer
    Joined: Feb 2002
    Posts: 2,211
    Likes: 177, Points: 63, Legacy Rep: 1673
    Location: Port Gamble, Washington, USA

    tspeer Senior Member

    I've seen a number of methods. Most have all three stays coming to a point just in front of the mast, attaching to a tang like is used for a conventional forestay.

    One method uses a chain link shackled to the tang, to which are attached the three stays.

    Another method is to have a double tang (forming a pair of jaws) to which is bolted the right-angle point of a triangular piece of stainless steel. The side opposite the point has three holes to which are shackled the other stays.
     
  3. brian eiland
    Joined: Jun 2002
    Posts: 4,788
    Likes: 156, Points: 73, Legacy Rep: 1903
    Location: St Augustine Fl, Thailand

    brian eiland Senior Member

    Mast Tang for Rotating Mast

    Many smaller cats with rotating spars simply shackled all three (forestay & two shrouds) all together onto one tang.

    I preferred to provide two separate attachment holes on the mast tang. The forestay was attached to a point that was closer to the face of the mast while the shrouds attached further out. This promoted a greater leverage by the windward shroud to firmly rotate the mast, since the forestay already had a greater angle and leverage, and would resist the rotation. This two hole arrangement necessitated the forestay hole as the lower of the two holes. (got an old drawing for my Firefly tri if I can find it)

    I always found it was easier to put a rotation limiter at the base of the mast, rather than a rotation inducer.
     

  4. SPJ yachts
    Joined: Feb 2007
    Posts: 29
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Queensland Australia

    SPJ yachts Junior Member

    F/stay rotating mast

    Henrikb,
    we used some dyneema as a f/stay attachment at the hounds .
    This with a positive main sheet angle on the boom and limited spanner at the mast should be ok
    I used this system on a 12mtr racing tri and worked a treat, just have to check the dyneema every 6 months or so cause this material does not like load on too tight a bend for too long but im talking here in the tropics and i guess you are talking non tropics. (SWEEDEN)

    good luck

    SPJ Yachts
     
Loading...
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.