apparent sheeting angles for self-tending stays'ls
 

I have conventional inboard side-deck tracks for my (non-selftending) staysail, but am looking into ways to make the small working staysail self-tending. The trick is, I'd like to keep my large flush foredeck free of booms, lines, and other contraptions.
I'm not sure what the rig is called (too modern), but I like the look of the self-tending rigs where the sheet is led vertically down from aloft to a track or horse, and then to the stays'l clew, with or without purchase.
Because I'm cheap/poor, the usual curved track and roller car just isn't going to happen... but a burly old-school bronze rod horse is totally do-able.
The question: For such an arrangement, what is the ideal width of the track/horse? Is there an ideal width? Would I best shape the horse to the sail, or build the horse to make a 10-12 degree sheeting angle (approx), and let the sailmaker build to suit?
Any ideas?

Ian McColgin
 

Ahoy osteoderm,

One very slick solution is the "camber spar." The one I had on Granuaile proved so popular that a number of other boats here-abouts got one.

Essentially the bent and pivoting spar proceeds normal from the luff to the clew. The tension is adjustable both directly by outhaul and by stay tension. The sail's luff is not quite straight, but angles a bit where the spar meets the luff on a roller.

The sail is perfectly self-tending and self-vanging from a center deck sheet block. It requires no winch to set up. The dangerous part of the spar, the clew, is nice and high. The sail is quiet anyway, with fewer tendencies than conventionally clubbed jibs to gybe back and forth off the wind and wonderfully docility when tacking. No need for helmets and padding on the foredeck.

The camber spar is not cheap and the sail must be made for it but once past the initial expense, it's really finastkind.

G'luck

Ian

Ian,

I happen to have a spare camber spar here in the boatyard. Neat idea, but it clutters up the foredeck just as much as a stays'l boom, and the sail can't be bagged on the stay, out of the way.
Otherwise, I agree that such spars work well enough, as they do on a couple of my client's Freedoms.

The horse should be long enough to get clew far enough outboard to sail the boat, like 10 deg off centerline, or longer if you will have the ability to control the cars movements or your boat doesn't point that high.
Making the track curved with the ends forward and up seems to make sense, for race boats anyway, as it makes the sheet tension the same where ever the car is travelled to, but in practice a straight track, or one that curves forward even, makes the sail move across easier through a tack, as it starts flogging sooner , and has no sheet tension as the car moves across. For the most sail area fit into that before the mast track, you will need a sail cut just to fit that track sheeting position, or re - cut that is. Often a clew board is used , sometimes a club on the sail to get the most area filled in.

What kind of boat do you have Yuri?
That will make a big difference as to the track and sail cut you decide to use.

Self tending boomless staysails are super great, we really love ours. Becasue our stemhead is so high, the sail is cut rather funny to get a good sheeting angle without a clewboard or club (the clew about 1ft lower to waterline than the tack) but the sail works great anyway.
I can go forward to bring the jib around while the helm is lashed up for a tack, and let the staysail just land on my back as it comes across. Cleat the new jib sheet, then a quick duck under the soft foot of the staysail and walk back along the windward deck. Easy to roll the sail up and lash it to the forestay for quick stoage too.

You have the right idea with that boomless staysail...