pocket luff sails with a trapeze?

Discussion in 'Sailboats' started by wind_apparent, Apr 29, 2008.

  1. wind_apparent
    Joined: Apr 2008
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    wind_apparent wind driven speed addict

    has anyone used a pocket luff sail on a trapeze equiped boat? would it be possible? Would have to figure out the spreader issue I guess. the spreaders would have to go on after the sail, and be sturdy enough to support a person on the trap, would this be possible? any Ideas?
     
  2. waikikin
    Joined: Jan 2006
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    waikikin Senior Member

    Wind apparent, maybe some velcro or zip on sails, velcro seems to work well on surfboard legropes with plenty of load
     
  3. Chris Ostlind

    Chris Ostlind Previous Member

    Some years ago, there was an early iteration of the solo performance planing skiff called the MX-Ray. It used a luff socked main for upwind work and it flew a spinny for offwind.

    The spinnaker mast "tang", if you will, was a re-enforced section of the sock with, I believe, a hard collar or stout webbing that wrapped around the mast in a pocket sewn into the luff sock securely.

    The whole deal was hung from a carbon stick that was self supporting.

    The boat was difficult to learn to sail, but when it was hooked-up, it ran like a bat.

    Chris O
     
  4. Doug Lord

    Doug Lord Guest

    The main on my first foiler were designed with a "luff pocket" as well as to be reefable. The rig was stayed-no spreaders. It could easily have used a trapeze. The sail had a three section zippered luff.
     

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  5. bistros

    bistros Previous Member

    It's been done. Search on "Bucko" to see a well documented build. One of the guys at my club has built a modern Moth that uses a stayed pocket luff sailboard style rig. The Hoot is definitely worth a look as well - no trap but it fills most of your checkboxes.

    I'm looking at doing a second rig for my boat with a rotating mast next year - I've got the carbon tube (I-14 mast) and we're thinking about stays and rigging. Take a good look at the Moths to get an idea of how to handle the stays.

    FWIW, pocket luff sails may be an issue at some locations - race rules require that there be some method of dropping sails either by the crew or rescue folks from a technicality standpoint. I personally hate having to fight for rigging space to rig a boat on it's side in the dinghy park.

    Then there's money. Pocket luff designs for what you are building aren't cheap or easy to get right. If you've got the budget, go for it. If you want to get foiling on budget, I'd think about staging the risk over time, with a conventional rig to start and progressively more complex over time (as you can afford it). I first trialed my boat with a sailboard style rig, then a 505 main on a Proctor D tube - a combination that is proven, available and well known. Now I'm moving to the chop top full battened sail on the Proctor D, then we'll get the carbon tube trialed next. Incremental progress and risk.

    Debugging design issues and tuning is really hard and critical. Eliminating variables and using known components makes the process far easier. I'm perfectly aware we've compromised potential performance at first, but it's enabled us to get the boat right in stages.

    In all reality the performance potential given up on rig compromises is minuscule in comparison to the software improvement possible in the operator. I know that even with a aluminum tube and a conventional main sail the area needing improvement on the water the most is me.

    Cheers!
     
  6. Hansen Aerosprt
    Joined: Mar 2007
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    Hansen Aerosprt Junior Member

    Very Possible.
    Either an opening in the mast luff sleeve with connection to the mast or a direct attachment to the sail. This sail has a 40cm wide luff sleeve.
    - Bill

    AM1a.jpg
    AM44a.jpg
     
  7. wind_apparent
    Joined: Apr 2008
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    wind_apparent wind driven speed addict

    Thats a really nice sail Bill, where did you get it?:D how do the spreaders work on a moth? I can't seem to find it on any of the construction blogs, and there aren't alot of close up pictures.......would that kind of spreader system support 85kg on a trapeze? I know that hydro moths sometimes have spreader problems on a good crash, so I would hate to crash with it under tension.... tahnks for the input.......
     
  8. wind_apparent
    Joined: Apr 2008
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    Location: boulder colorado

    wind_apparent wind driven speed addict

     
  9. Doug Lord

    Doug Lord Guest

  10. Hansen Aerosprt
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    Hansen Aerosprt Junior Member

    WA:
    I recently made that sail for Andy Mills' Fastacraft Prowler (Moth.) The rig is fairly standard for that boat. More pics are here: < http://www.hansensails.com/Forum/forum_posts.asp?TID=115 > Sorry, but I can't say much about a trapeze on a Moth - no experience there.

     
  11. Hansen Aerosprt
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    Hansen Aerosprt Junior Member

  12. wind_apparent
    Joined: Apr 2008
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    Location: boulder colorado

    wind_apparent wind driven speed addict

    been talking to him on the Hansen sails forum as well as here, so we'll see what comes about.
     

  13. wind_apparent
    Joined: Apr 2008
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    Location: boulder colorado

    wind_apparent wind driven speed addict

    so I looked up the Bucko, funny how close our numbers were to eachother's, tells me I'm probably right in there...... shows that you can't really mess around "too" much and still have the boat perform......
     
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