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Doing the Death Plan
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I have a genneker with a snuffer on my 59ft Oyster monohull and I find it too hard to use short-handed so the sail just sits in the lazarette taking up space. I am considering getting a Karver top-down furler and i wonder if anyone has any experience using these at sea. They look and sound good in theory and i know that the Volvo boats use them offshore. Feedback from happy users out there would be most welcome.
 

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I just purchased a Selden GX15. I have deployed and furled the sail in light air at the slip but not while sailing. I am leaving for a 2 week cruise today and plan to use the furler extensively. I also plan to film it in operation and post to my website.

I previous had an ATN sock and tacker and did not like wrestling with it on deck. Snubbing the sail if the wind increased suddenly was always difficult and prompted me not to use it very often.
 

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The flatter the sail the better they work. A Gennaker does work better then a spinnaker. a Gennaker is really a asymmetrical spinnaker. they both have a soft luff. if you are using a reaching asymmetric they work well if the sail is designed for it. The head needs to be soft with out a lot of stiffening panels. an extending spinnaker crane on the top of the mast helps to keep the torque rope out away from the forestay and furled jib. The stiffer the head of the spinnaker the more the sail tends to hang up on the forestay as the torque tries to wind the sail around the torque rope. This causes the torque rope to wind up and twist like a rubber band on a model airplane and once the head does start to wind up the sail it will release the twisting and over wrap the sail. The sail will look like it is wrapped up just fine until the next time you try to unfurl the sail and it will be wrapped around the torque rope and will not unwind properly. Then comes the very messy take down. a bow sprit also helps a lot because for the furler to work properly the torque rope needs to hoisted tight and free to wind up the sail without it dragging on the forestay or furled jib. Get the stiffest torque rope you can for size of your boat. When furling the sail, if the torque rope gets any wind up, the sail will not unfurl the next time. Carver makes a good rope and furler but will still over wrap if not handle by an experienced crew, it is not something that can be done by one person like all the ad videos, where they show it being done in very light wind. The more wind the more crew skill needed to make it work and it takes practice like any spinnaker hoist and douse. The new Profurl looks like a good idea with the furling beads on the torque rope. I have yet to try one but just the fact they invented the idea lets me know that they were having the same problem with wind up and sail over wrap as the other manufacturers do. They don't talk about it unless you ask and if they tell you it does not happen then don't buy from them. the Volvo 70 guys have a very fast boat so they sail downwind with different apparent wind angles so they have very flat sails compared the one for a cruising boat. they also make it look simple but they have a lot of practice under their belt. most of their sails are hard luff sails like a jib or code zero. if one is trying to fly a old symmetrical as a asymm. on a furler then forget it.
 

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Doing the Death Plan
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Discussion Starter #5
Thanks Overbored for taking the time to share your experience.
I have just had a bowsprit made with a 2:1 tack line that runs through the pole and back to the windlass and the furler will connect to that. I have also recently upgraded my spi halliards to dyneema so i think i should be able to get decent tension on the stay. My kite is more a reaching asymmetric so i am hoping it will suit. I will check the head as you suggest. Allspars in the UK supply the Karver product and they use a Navtec stay - the larger size apparently. They have also offered to crew on my boat at the regatta in October to show me how to use it. I think i will go for it - i find the snuffer just too hard in a rolly sea.
 

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here is some more stuff to read. I also heard that the Navtec stuff is the best. I have not tried it but was thinking about getting some. they are the most expensive. if you get it Let us know how it works
 

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Furlers for asymmetric

I have no experience (yet) with top down furler.

I have a Facnor AFX with a central furling line.
The difference from a top down is that it have a swivel top & bottom and a thin line attached mid luff that is used to furl the sail from the middle.

The sail I'm using has can be used in a wide AWA angle from DDW to 90° by adjusting the stretch on the luff.
The only adaptation for the furler is a reinforced eyelet in mid luff.

It's important that the head and tack can rotate freely during the furling process.

Here I'm sailing DDW with the tack eased, you can see the furler flying, the furler sits on a 1:2 tack line that can be adjusted from the cockpit.


In this picture you can see the central furling line going to the torsion stiff rope.


The tack swivel


Head swivel


Maybe I'm wrong but I think Facnor has patented this design..

I'm planning to convert my system temporarily to a top down just to compare the two different designs - out of curiosity:):)
 

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Doing the Death Plan
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Discussion Starter #8
thanks Knuterikt
i havent seen your system before. its be interesting to see how the top down compares. i will certainly report back on this thread how i get on once i have it installed around the end of September.
i definately need a light air solution for the world ARC which we are planning to jon next year.
 

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I have the same system and have a lot of problems with spinnaker over wrap. we tried the furler as a top down and found that the torque rope is way to light to handle top down furling. there is way to much twist in the rope by the time the top starts to wind up. it does work on the the A4 and A3 but not on the A2 it is to big
 

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I have the same system and have a lot of problems with spinnaker over wrap. we tried the furler as a top down and found that the torque rope is way to light to handle top down furling. there is way to much twist in the rope by the time the top starts to wind up. it does work on the the A4 and A3 but not on the A2 it is to big
So you are using the AFX?
What model furler and size of sail?

Have not had problems like that - but both the tack and head spin freely (not touching anything)
But furling with to much pressure on the sheet can case uneven furling.
It's installed with torque rope supplied by Facnor.
 

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that what I have same type with the swivel at the top and bottom. i works on the smaller spinnakers but not on my to big ones which are 1000 SQ ft ( 93 s m )and 1200 Sq ft (112 sm) the Facnor rope is not as stiff in torsion as the colligo but it is also 8 mm vs 11 mm. we are using the 11 mm colligo set up for top down and it works much better. Still we have to be very careful when doing the big sail. it has a 47' luff with a 33 ' foot. takes a bit to furl.
 

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I did a test conversion to top down on my AFX, temporarily disabling the top swivel so turning the anti twist rope would turn the head of the sail.

I did this on a day with wind speed = 0.

After lots of pulling on the furling line the top of the asymmetric started to furl after the first 3 feet (= 1 m) I stopped as I noticed that the rope where twisted a lot..

From this little test it's obvious that top down needs a better anti twist rope than the AFX central furling line design.

Checked with the local rigger, seems there is a rapid ongoing evolution with the anti twist ropes.

Mine is probably the first generation rope for the AFX system, Facnor sell better anti twist ropes and there are also others who make competing products.

The Facnor way of attaching the rope to the swivels make attaching some of these ropes a demanding task.
Facnor uses a wedge in the middle of the core to attach the rope - some of the ropes one can buy use lots of glue in the core so its difficult to get the wedge in place.
 

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We are using a code zero (G0 from North) on a Schaeffer roller, but it's not this top down design. I too am very interested in hearing more. Been thinking about a asym, and this system looks intriguing. We are fractional with a good attachment point forward of everything (we made the anchor roller a little longer) so we can tension the torque rope pretty well.
 

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I did a test conversion to top down on my AFX, temporarily disabling the top swivel so turning the anti twist rope would turn the head of the sail.

I did this on a day with wind speed = 0.

After lots of pulling on the furling line the top of the asymmetric started to furl after the first 3 feet (= 1 m) I stopped as I noticed that the rope where twisted a lot..

From this little test it's obvious that top down needs a better anti twist rope than the AFX central furling line design.

Checked with the local rigger, seems there is a rapid ongoing evolution with the anti twist ropes.

Mine is probably the first generation rope for the AFX system, Facnor sell better anti twist ropes and there are also others who make competing products.

The Facnor way of attaching the rope to the swivels make attaching some of these ropes a demanding task.
Facnor uses a wedge in the middle of the core to attach the rope - some of the ropes one can buy use lots of glue in the core so its difficult to get the wedge in place.
That's good information, thanks...

I haven't yet had the chance to use a top-down furler myself, but I have some reservations whether or not they're quite there, yet...

I'm thinking about having a new Code 0 made, with the possibility of a high torsion rope built into the luff... I use the ordinary Facnor furler, and my current Code 0 has always just had a spectra luff... It takes a lot of wraps at the bottom of the sail before the furling starts to 'migrate' up to the top, and unless you twing the sheet further forward to exert a strong downward pull on the leech, you'll usually wind up with some loose sailcloth up at the top...

My water generator uses a high-torsion rope, and it's not easy stuff to deal with... One of the things I really like about my Code 0 as is, is with the softer luff, it can be stowed in an incredibly compact package. I'm concerned I'll wind up with a much bulkier package if I go with a high-torsion rope... So, we'll see, but I may wind up simply going with what I've got again, it's not that difficult to deal with...

With an asym, I still think a sock is the way to go on smaller boats, but of course I'm not sailing a boat the size of the OP... Biggest rig I've ever used a sock on was a Trintella 50 - which is a massive rig for a boat of its size - and it definitely was a challenge to manhandle when the breeze came up, we often had to lead the downhaul to a winch to begin the capture of the sail...
 

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I just purchased a Selden GX15. I have deployed and furled the sail in light air at the slip but not while sailing. I am leaving for a 2 week cruise today and plan to use the furler extensively. I also plan to film it in operation and post to my website.

I previous had an ATN sock and tacker and did not like wrestling with it on deck. Snubbing the sail if the wind increased suddenly was always difficult and prompted me not to use it very often.
So what's the verdict? Curious to get your opinion on it.
 

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I was out cruising for two weeks and used the Selden GX 15 furler 3 times. It worked great after a little tuning. I am very happy with how it works and how easy/quick it is to deploy and retrieve. I made a quick video showing how nice it works. No real specifics on the video but it shows unfurling and furling.

The real advantage IMO is that you can hoist the sail in the morning not knowing if you will use it. With the ATN sock I had to carry the huge bag up on deck and hoist the sock/sail and attach the tacker every time I wanted to use it. This usually meant I would not bother using it if I had a broad reach or DW leg less than an hour. With the furler I can easily roll it out for 5 minutes if I want.

You cannot leave it up indefinitely as there is no UV protection for the sail. We hoist it before setting out if we think we will have any broad or DW legs. It is also much easier to setup last minute if needed.

And it rolls up into a space less than half the size when it was in the sock so transporting and storing the sail/furler is much easier now.

Here is the video:
 

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Looks great, thanks for sharing. Agree about the inconvenience of sock. This might be a nice addition to our inventory.

Hard say for sure in the video, but it looks like the tack is inside your bow pulpit. No sprit needed? If gybing, would you just furl/gybe/deploy? Same DW angles that you saw with the assym?
 

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Looks great, thanks for sharing. Agree about the inconvenience of sock. This might be a nice addition to our inventory.

Hard say for sure in the video, but it looks like the tack is inside your bow pulpit. No sprit needed? If gybing, would you just furl/gybe/deploy? Same DW angles that you saw with the assym?
The tack is inside the pulpit. I have a lot of space between the headstay and the pulpit. No need for sprit on our Caliber. No need to furl when jibing. Sheets are led for outside jibing. Same procedure as if there is no furler.
 

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I am trying to build a top down furler for my 8m yacht.
There are 2 things I dont understand.
1. Why is it necessary for the tack to be on a rotating bearing independent of the bottom unit. Could it be stationary but independent of the turning parts?
2. What causes the bottom of the sail to start turning at a certain point in the furling process when an independent swivel for the tack is fitted? I have watched the videos over and over and I can't work it out.
Cheers
 
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