Self tending jib

[Charly]

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

 

[Richard Woods]

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

 

[philSweet]

Can you post a sketch of the jib arrangement?

 

[Charlyipad]

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

 

[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.

 

[Charly]

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.

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

Is self tending over-rated?

Thanks for any opinions

 

[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.

 

[Richard Woods]

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

 

[gggGuest]

Self tacking jibs don't actually last long because of the very high leech loads compared to a lower AR sail

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.

 

[Charly]

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 . 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.

 

[CT249]

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.

 

[messabout]

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.

 

[Richard Woods]

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

 

[bruceb]

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