Winchless

Maybe you have heard of the "winchless" system which has established in the Dragon class.

However this system has one weak point : It needs two ropes, one for the rough adjustment and one for fine adjustment. This means you have two ropes wích might cause chaos in the cockpit.

Has anyone of you an idea how to sheet a jib or genoa for a 30ft. boat without a winch ? Obviously you will need some "automatic" system that comes into action in the moment the sheet gets loaded. So when tacking the first meters (Sorry, I am from germany, thats why metric) of the sheet do not have any load and the power ratio should be 1:1 (fast). When the sheet gets load you will probably need something like 1:8 or even 1:16.

Any idea ?

Thanks

Jan Duken
Berlin, Germany

 

There are two ways that come to mind: withhold your crew's beer until the sheets are taut, or momentarily point into the wind while you take the slack off the sheet. The second method was used in ships for centuries.

 

Double ended system

This should be a pretty simple solution. Something similar has been done with mainsheets for a long time. I would consider this for jibs on a 30 footer, but certainly not a Genoa. This also gives the 2 lines per side, so maybe you have already considered this and are looking for something different.

You would attach a single block to the clew of the jib. Many boats do this to achieve a 2:1 or 3:1 jib sheet. Hobie cats are one example.

You would use a side-by-side double block on the jib track car.

The sheet would run around the single block on at the clew. One end would run from the block through one of the sheaves on the double block on the jib track, then through a single foot block with a ratchet, then to a cleat (like a Harken cam matic). This would be your course trim at 2:1 during tacks.

The other end of the line coming off of the block on the clew of the sail would run through the other sheave on the double block on the jib track and attach to a 6:1 purchase with plenty of distance between the blocks. That would be your fine tune at 12:1.

When tacking you would make sure your new side fine tune (12:1) was released. A halyard ball would keep the head of the 6:1 purchase from jamming up into the block on the jib track.

You would cast off both course and fine tune on the old tack and haul away on the 2:1 on the new tack until you were at a pre-set mark (not fully trimmed) or until you couldn't pull any more. Cleat the course tune. Then you would use the fine tune to bring in the jib to the proper trim and cleat the fine tune, or play by hand in the puffs.

I hope this is clear. If not, maybe I can make a sketch.

 

Thanks fot this. But you describe the system as it is established on the dragon.

I am looking for a system with one rope only that you have to pull. The "two rope version" is definitely easy and solved. I am in touch with guys at Harken and even they do not know how to reduce this to a "single line system".

My best guess so far is that you need to integrate a traveller like car system which only comes into action at a certain point (lets say for the last 60 cm (2 feet). The sheet goes through the whole block and tackle system and starts pushing the car after awhile.

The problem is that you have to make sure that when you release the jib (or genoa) you do not get a big mess in the "block and tackle".

BTW A system that first works with a 1:4 and then "automatically" with a 1:1 is very easy. You just take a block and tackle system with three blocks in a row. The one in the middle is moving. In the moment the middle block is at the other end you will have automatically a 1:1 system. (The negative effect is that you have a few blocks involved at this stage which just cause friction.

Whatever you find please let me know.

Thanks

Jan

 

The magic wheel?

Hi,
This is a quite old thread, but I have been looking for answers to the same question.
When searching I came across something called a "magic wheel", used for backstays on IMX boats.

I imagine something like this
http://www.sailtek.org.uk/USERIMAGES/2004 Frederiksen Catalogue pg160.pdf
could possibly be used. Especially attractive the option with taper giving more speed early, and more advantage closer to the end position.

Have anyone seen or heard of this used for anything except backstays?

Kind regards

Patrik

 

Are you talking about a non overlapping jib on a traveler . A one sheet system is common on non overlap jibs . This one sheet is two to one at the traveler and could be wheeled, hydraulic rammed or magic box type purchased with a single line.

 

Magic wheels

Hi,

I was thinking of a overlapping jib (more than the 5% possible with selftacking W shaped rail)

I saw a winchless solution on Harken for 150% genoa, and came to think of the magic wheel.

http://www.harken.com/DeckLayout.aspx?id=14769

//Patrik

 

Then it will have to be a Hi Low system with two control lines. the Genoa sheet, then fine tune.

 

Hi Michael,

If I don't read the magic wheel PDF wrong, it is in some cases designed with a constant diameter on the line you pull with your hands, and a tapered diameter on the line going to the backstay, sail or whatever you control. Starting with a large diameter giving the speed to get the sails roughly right, and then tapering giving fine tuning possibileties.
Question is only that would work in real life?

//Patrik

 

Ive only ever used a wheel for backstay adjustment. Id have to look at a wheel and think about it.

A Harken type traveler could work but it would be very long and slow to tack.

The same would be true of a wheel. Slow tacking