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Old 08-08-2009, 20:57   #1
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Unique Twin Jib Rig

A number of years ago i remember seeing an article on someone who was flying twin jibs that had a whisker pole attached to each clew (so far so good) but the interesting part was that the inboard side of each pole was attached to the other by a tongue-and-groove arrangement and the whole thing flown from a halyard so the assembly was able to be used from a broad reach to a dead run. If this is familiar to anyone who could point me to the article that's be great.
Thanks!
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Old 08-08-2009, 21:42   #2
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Why not just fly a chute??
An asymmetrical spinnaker would not need 2 poles or even one.
No head clunking heavy hardware either. No topping lift, etc.

Steve B.
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Old 08-08-2009, 21:45   #3
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Is it a Twistle Rig?

See : The Twizzle Rig or Twistle Rig for Downwind Ocean Sailing
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Old 08-08-2009, 21:49   #4
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Bingo! Thanks neelie!
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Old 08-08-2009, 21:58   #5
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I'd love to try it out apparently by virtue of the CE being so far forward it is self steering. Odd that its not used more often.
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Old 08-08-2009, 22:19   #6
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Quote:
Originally Posted by S&S View Post
A number of years ago i remember seeing an article on someone who was flying twin jibs that had a whisker pole attached to each clew (so far so good) but the interesting part was that the inboard side of each pole was attached to the other by a tongue-and-groove arrangement and the whole thing flown from a halyard so the assembly was able to be used from a broad reach to a dead run. If this is familiar to anyone who could point me to the article that's be great.
Thanks!
You might want to check out this thread: http://www.cruisersforum.com/forums/f48/downwind-sails-5961.html. Member maxingout (Dave) at post #12 in that thread offers some of his personal experience using twin headsails on his circumnavigation.

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Old 09-08-2009, 19:56   #7
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Thanks Tao- Well a spinnaker doesn't make her roll much don't see how twins would be worse ( as long as I stay away from resonance). Cheap would be to use both slots in my present Harken furler. Better would be twin stays (which would entail making up parts). I already have an uphaul so there's no extra hardware there.

I've read in the "old days" it was common to set twins ( or a raffee for the well heeled)
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Old 09-08-2009, 20:25   #8
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I've used a twizzle rig and was most impressed.

- it seemed to substantially reduced roll - I assume because more of the sail area of a genoa is down low compared to a spinnaker. There's none of the oscillation of a high big roached sail.

- we sailed with unequal size headsails - we set the larger one to leeward and the rig seemed quite controllable. Much less twitchy than a spinnaker.

- be sure to rig enough up-hauls, down-hauls and other hauls to keep the inboard end of the poles under control. Things are getting pushed from all sorts of directions.

- it's easy to roll up the rig without striking the poles or even going on the foredeck. I'd never leave a spinnaker up after dark but the twizzle presents less risk than a gybing mainsail.

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Old 17-09-2009, 14:42   #9
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I posted the twizzle details on the web in the link above in 2004 after our trip from Cape Town to Tobago where we used the twizzle rig most of the way.

The big advantages were lack of chafe (a big issue on long trips) and the ability to easily reef from the cockpit short handed.

In the Trades we carried the rig day and night for weeks on end and it was great.

We had two jibs sewn together on a single luff tape hauled up a single furling gear. Ease the poles forward and roll up a bit and she's reefed. Simple.

We had 30 knots+ in the ITCZ at night and I was able to reef her down by myself without calling the watch below who slept right through it!

The rope universal joint (which takes the inboard ends of the poles plus the uphaul and downhaul) was the most simple and the most effective. We started off with an expensive stainless fitting and then later threw it out in favour of a rope cricifix, knotted and served, which allowed the pole ends to rotate in all directions.

If anyone needs further descriptions please ask.
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Old 17-09-2009, 14:49   #10
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Thanks Smacksman. I can see an uphaul and a downhaul on the U-joint". Is lateral motion control just with the sheets? Also if you have more shots or description on how to make up the cross, that's be great.

I have one heavy Al spinnaker pole so i was thinking of a couple of whiskers for this.
Any other suggestions?
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Old 17-09-2009, 15:08   #11
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Yes, twins and twin headstays were pretty highly touted for a while by some , especially for the long down wind runs in the south pacific.... then furlers were invented...
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Old 17-09-2009, 15:47   #12
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Thanks Smacksman. I can see an uphaul and a downhaul on the U-joint". Is lateral motion control just with the sheets? Also if you have more shots or description on how to make up the cross, that's be great.

I have one heavy Al spinnaker pole so i was thinking of a couple of whiskers for this.
Any other suggestions?
Hi S&S (is that Sparkman & Stephens?)

The rope crucifix is just a bit of half inch Marlow 'braid on braid' lashup - not really a knot of known name though I'm sure there is one (jury knot comes to mind). Anyway, the loads are not massive so a bit of sewing and whipping will do the job. There is a video clip of me moving the ends of the poles in 20+ knot Trades with no problem.

The pole end fittings were off the shelf spinnaker pistons and the poles were made up from ally scaffold poles with smaller tube pop riveted in the ends to reduce the diameter to fit the spinnaker fittings. Not being anodised did not create a problem.

Lateral motion is controlled by the fact that the length of the poles is about 10% more than the chord of the jibs.

The tension on the downhaul controls how tight the clews are stretched apart.

The ability of the universal joint to swing athwartships in front of the mast helps to dampen the roll. You will still move about quite a bit so it is silly to say that the Twizzle rig stops rolling completely as 'holes' and 'silly waves' will always throw you about in mid ocean no matter what you do.
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Old 17-09-2009, 16:40   #13
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Yeah. Twizzle rig and its variations. On a sloop if you can fly the jibs between the mast step and the mast top (you need shorter jibs than full forestay length for this) and angle them "out" (clews further than tacks), then you get a lovely self-steering downwind rig - no need for windvane!

But I have not seen a single boat sailed like this. Maybe there is a catch then.

b.
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Old 17-09-2009, 17:23   #14
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During our 2008 return from Hawaii I flew twin jibs with a whisker pole on one sheet and the other sheet run through an end-boom snatch block. Here are some photos of the arrangement: VALIS. The next two pictures show some other angles.

The twin-jib rig was very easy to sail, and I'm probably going to have a lightweight twin sail/single lufftape made up before next year's Pacific Cup. A symmetrical spinnaker will usually be faster, but the twin headsail is very forgiving, and under it we it rolled less than with a main and jib running wing-and-wing -- I assume because the center of effort is far forward and better balanced.
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Old 18-09-2009, 02:16   #15
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The self-steering aspect of the twizzle rig was not an issue with us. To achieve the 'clew ahead of the tack' position with the jibs unfurled would require even longer poles.

When designing from scratch the governing factor of jib area is the length of the pole you can stow on board. Our poles were stowed on deck and so limited by the curve of the deck. Longer poles could have been stowed up the lower shrouds. We didn't have that problem as we had a No.2 jib already and managed to find a second hand jib that pretty well matched it and then made the poles to suit the jibs.

We set the twizzle with the clews aft of the tacks which created a nice lift to the bows as demonstrated by the dappling of the ocean by the downdraft from the jibs. Autohelm 7000 did the steering very ably all the way with the exception of me having to replace the magnetic clutch 600 miles off Brazil with my head upside down in a cockpit locker in 20 foot swells!

Where you will get the 'self-steering arrow flight' effect is when you are well reefed down. Then, as you let the poles forward and roll up the jibs (without easing the downhaul) the clews naturally go ahead of the tacks.

But now you are talking of serious wind if you need to reef that much, say 45 knots+ and by then the short handed cruising man is thinking of lying ahull in your own slick (which works well, bye the bye)

Spinnakers are good fun and really pull her along but the thought of a husband and wife crew dropping a 3,000 sq.ft. bag when the wind pipes up on a prancing foredeck just doesn't bear thinking about IMHO.

Are we cruising or racing here? Does another day or three at sea make a difference?
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