Self tending jib

Discussion in 'Sailboats' started by Charly, Jan 23, 2015.

  1. Charly
    Joined: Dec 2009
    Posts: 429
    Likes: 32, Points: 0, Legacy Rep: 377
    Location: st simons island ga

    Charly Senior Member

    hey guys, I am setting up a homebuilt cat for the first time.

    The plans call for a self tending jib, with a Schaefer track, two blocks on cars, and a block at the clew.

    I have zero experience with self tenders. The first question I have is- How do you backwind the sail when you need to heave to or get out of irons?
    Thanks
     
  2. Richard Woods
    Joined: Jun 2006
    Posts: 2,179
    Likes: 145, Points: 63, Legacy Rep: 1244
    Location: UK, USA and Canada

    Richard Woods Woods Designs

    You hold the clew by hand to back the sail. And, as you'll need barber haulers when off wind to control twist, you can use those when you heave to or sail off an anchor

    Most modern catamarans don't get in irons

    Richard Woods
     
  3. philSweet
    Joined: May 2008
    Posts: 2,233
    Likes: 140, Points: 63, Legacy Rep: 1082
    Location: Beaufort, SC and H'ville, NC

    philSweet Senior Member

    Can you post a sketch of the jib arrangement?
     
  4. Charlyipad
    Joined: May 2014
    Posts: 218
    Likes: 7, Points: 18, Legacy Rep: 57
    Location: St Simons is ga

    Charlyipad Senior Member

    Phil, I can't tonight on this iPad, but it has a seven foot t track set up just forward of the mast. the plans aren't real specific about how to set it up. Seems to me that with two separate standup blocks on the track and then a block set up on the clew, you would start at a becket on the clew? Then through one block and back up to the clew, then to the other standup block, and then I guess it is up to the individual needs to lead the sheet from there to somewhere it can be handled the easiest. in my case that would be back to the helm.

    I have no idea yet how this boat is going to respond, but I want be able to control the sheets and the daggerboard controls from the helm, and that includes back winding the jib.

    Any comments appreciated

    Here is a page from the study plans. Fwiw
    http://www.multihulldesigns.com/images/charter/36chcatTOP.GIF
     
  5. gggGuest
    Joined: Feb 2005
    Posts: 808
    Likes: 17, Points: 18, Legacy Rep: 76
    Location: UK

    gggGuest ...

    I've seen boats rigged with backing lines, which were just light lines led to the car via fairlead at the end of the track and back to somewhere handy. Normally loose, you just grabbed one if you needed to back the jib. No cleats, just the end fastened.
     
  6. Charly
    Joined: Dec 2009
    Posts: 429
    Likes: 32, Points: 0, Legacy Rep: 377
    Location: st simons island ga

    Charly Senior Member

    I could do that easy enough. It would make the deck more complicated though, and it seems to me, the whole point of the self tending exercise is to simplify the deck. The thing I am wondering at this point is self tending worth the trouble? I have to do something real soon, and whatever it is, is probably going to be expensive:confused:

    Is self tending over-rated?

    Thanks for any opinions
     
  7. gggGuest
    Joined: Feb 2005
    Posts: 808
    Likes: 17, Points: 18, Legacy Rep: 76
    Location: UK

    gggGuest ...

    It depends on where what and how you are sailing. But if you do a lot of short tacking with a minimal crew self tacking may well be preferred. Good too if you just want to point the stick and enjoy your surroundings. The jib probably flogs less whilst tacking too, so will very likely have a longer life, and tacking is more peaceful with less noise and drama. OTOH if racing *very* seriously then the jib settings are critical, and I have doubts about how accurately you can maintain them with the self tacking jib.
     
  8. Richard Woods
    Joined: Jun 2006
    Posts: 2,179
    Likes: 145, Points: 63, Legacy Rep: 1244
    Location: UK, USA and Canada

    Richard Woods Woods Designs

    Self tacking jibs are great when tacking, not too great the rest of the time. They first became popular in Scandinavia where you do a lot of short tacking between islands, often in "metre style" long narrow boats which carry their way well through a tack.

    Serious racers use them in the Star, Etchells, 49er etc. Boats that point high and sail slow to windward, or boats where the crew control the main sail and spi. Self tacking jibs don't actually last long because of the very high leech loads compared to a lower AR sail

    Richard Woods
     
  9. gggGuest
    Joined: Feb 2005
    Posts: 808
    Likes: 17, Points: 18, Legacy Rep: 76
    Location: UK

    gggGuest ...

    You've lost me there completely. AR presumably you mean aspect ratio? Why would I have a different aspect ratio just because I've got a self tacking jib? I'm working up a design for a self tacking jib for my boat which already has a none overlapping jib and I can't see that I'll need to make significant changes to the sail at all.
     
  10. Charly
    Joined: Dec 2009
    Posts: 429
    Likes: 32, Points: 0, Legacy Rep: 377
    Location: st simons island ga

    Charly Senior Member

    Yeah, I'm not the racing type, but I do a lot of tacking around where I live, often short handed, or with crew of the "ballast" variety :D. So I need to be able to do as much from the helm as possible without too much fuss.

    So, with self tenders, please correct me if I have any of this wrong. You set the limit of travel for the two cars with the stand-up blocks at some optimum point so when you tack they will travel to the same place and stop there. (or are they fixed on the track?) The end of the sheet has to start somewhere, so I guess it could be made fast either on one side of the track, or on the clew of the sail at a becket ? then it is rove through the blocks and the control end goes to a cam cleat somewhere? This is a smallish jib, full battened, a little over 100 sq ft I think.
     
  11. CT249
    Joined: May 2003
    Posts: 1,228
    Likes: 65, Points: 48, Legacy Rep: 215
    Location: Sydney Australia

    CT249 Senior Member

    Check out Formula 18 cats; they use self tackers and because they are a large class, they are well sorted out. Tornadoes are a smaller class but they also use self tackers and are very well sorted. That should give you a good idea of the basic setup.

    If you just use stoppers on the track you will meet trouble when reaching, because the car position will be too far inboard. It's easy to use a single line that adjusts the distance the car can travel along the track. That will also allow you to sheet out when you are facing strong winds and are overpowered.

    I do tend to think that the slightly shorter foot of self tacking jibs tends to have a significant impact on speed in very light winds, and AFAIK it's well accepted in beach cats that they reduce reaching speed. But the ease of handling is obviously terrific.
     
  12. messabout
    Joined: Jan 2006
    Posts: 2,985
    Likes: 189, Points: 63, Legacy Rep: 1279
    Location: Lakeland Fl USA

    messabout Senior Member

    Dare I mention the possibility of a club with outhaul and vang? One central turning block would lead a single part sheet toward the helm position. If the sail is too big for a single sheet then a multiplier tackle somewhere in between the helmsman and the turning block. No track required. Simple, cheap and it works.
     
  13. Richard Woods
    Joined: Jun 2006
    Posts: 2,179
    Likes: 145, Points: 63, Legacy Rep: 1244
    Location: UK, USA and Canada

    Richard Woods Woods Designs

    I assume by "club" you mean a boom? I have sailed on boats fitted with staysails like that. One problem is the angle of the forestay means the jib may not lower easily unless the boom is raised first. Reefing the jib is harder and, most of all, the jib boom gets in the way of anchoring etc when not in use.

    Not sure if it is a cheap option either, you need a boom with a special gooseneck and more blocks than a conventional self tacker track

    But check the Berig Camberspar

    Richard Woods of Woods Designs

    www.sailingcatamarans.com
     

  14. bruceb
    Joined: Nov 2008
    Posts: 1,204
    Likes: 38, Points: 48, Legacy Rep: 214
    Location: atlanta,ga

    bruceb Senior Member

    size matters

    C, what size boat? I have a 24' tri with a self tacker that I use a lot. Always for cruising, and sometimes short handed racing. With a tri, I haven't had to back wind it, and I and my crew think it is wonderful. It is old, built heavy, and very effective. I would strongly recommend it.
    B
     
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.