THinking of adding a furling Jib

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Re: THinking of adding a furling Jib

Postby 109jb » Sat Sep 08, 2018 11:42 pm

The swivel will attach to the mast fitting where the stock forestay is attached. There is no possible way I could attach the swivel to the jib halyard because there would not be enough length to the stem fitting . To do that I would have to have the luff of my jib shortened.
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Re: THinking of adding a furling Jib

Postby 109jb » Sun Sep 09, 2018 11:23 am

I slept on it and thought that I could remove the top forestay attachment and move the jib halyard block there. This would allow me to use the jib halyard to adjust the jib/forestay tension. A benefit of this is that I could lower the jib without having to lower the mast. I would have to remember to run a line to the mast to support it while the jib is down.

My only fear with this is that if the Jib halyard were to unexpectedly come loose there could be lots of damage to things since the jib luff will also be the forestay. My current jib halyard is amsteel spliced to double braid with only about 1 foot of double braid in action once the jib is hauled up. That should provide more than enough strength.

As I typed I was thinking of ways to make it a bit safer using this method. Imagine the jib hoisted. I could splice an amsteel eye to the jib halyard just above the mast tabernacle that I could connect to an eye strap/shackle on the lower part of the mast as a safety device. The setup would provide minimum jib/forestay tension and even if the halyard came off of the cleat the mast couldn't fall and get damaged. The double braid end of the halyard would still be available to add tension, but if loose the spiced eye would keep things taught enough to not get damaged. Thinking further, if I make the minimum tension adjustment at the spliced eye, then I could just leave the stem fitting at the bow alone and adjust the tension at the mast through the amsteel halyard. The more I think about this the more I like it.

Let me know what you guys think.
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Re: THinking of adding a furling Jib

Postby GreenLake » Mon Sep 10, 2018 2:24 am

Yep, that safety scheme sounds about right.

If you have a deck stepped mast (tabernacle) then my assumption would be that you don't need a lot of tension in "safety" mode, just enough that the mast can't fall backward.
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Re: THinking of adding a furling Jib

Postby jalmeida51 » Mon Sep 10, 2018 10:32 am

Will you get enough tension on your jib halyard without some kind of purchasing power? Your jib halyard has to be tight to furl your jib. You don't want to have a saggy luff wire since you will be furling a 150%. Also your luff wire is your new fore stay and you need tension on it to tension up the side shrouds if you are using fixed shroud adjusters. Another way to get tension on the jib halyard is to use another halyard connected to your trailer winch and get your tension, then connect the bottom of the luff wire to your furling drum. Have you changed your mind on using a threaded rod and nut to get tension? John
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Re: THinking of adding a furling Jib

Postby GreenLake » Mon Sep 10, 2018 2:02 pm

You'll want to be able to adjust halyard tension because you would want to adjust the luff sag of your jib to wind conditions. The same adjustment could be used to help furling - although I can't recall that being an issue on the one boat that I used a furler like that.

Even regular, non-furling jibs may be built with luff wires. In that case, the halyard needs to be able to be tensioned quite high, as the idea is that the internal luff wire will take over from the forestay when tensioned and allow you to control the luff sag via the halyard. This definitely requires some purchase; not very much, I think, even a 2:1 makes a big difference.
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Re: THinking of adding a furling Jib

Postby 109jb » Mon Sep 10, 2018 2:04 pm

I'm still undecided as to what route to go. This will likely be a task I accomplish in the off season. For now I will just use the hanked on genoa.

I have the wife liking the idea of sailing and SHE has already planned 2 trips for us. The first is a 4 day trip to Kentucky Lake this month, and the second is a trip to the Florida Keys next March. That's the reason I'm working on the furler and my other post about the mainsail reefing in case we get into uncomfortable winds on these trips. The mainsail reefing will definitely be done before or Kentucky trip.

I haven't discounted the option of replacing the forestay with a system like I had drawn above with the screw adjustment for tension. Just have to de-tension and lower the mast to remove the sail.

I like the idea of using the halyard because it would allow me to drop the sail and store it without having to drop the mast. As far as getting enough tension, with the amsteel halyard it shouldn't stretch much at all and I figure I can get about 150 pounds tension the way it is now with the horn cleat once tied off and everything. Does that sound like enough? I could probably put a cam cleat or rope clutch on and boost that up a bit since it would grab and I could essentially get all the tension I could apply without losing any during tie off.

The halyard setup is probably what I will try first since it uses the stock stem fitting and I can attach a halyard block to the mast forestay fitting just to try it.

On another note, I found some info on the internet that says the Ronstan R76 furler can hold enough line to roll a jib that has the perpendicular distance from clew to luff of 2500 mm (8.2 feet). Bummer!! that isn't enough for a 150 genoa on the daysailer. I am therefore planning to make my own, which is why it will likely be an off-season project. Maybe if I burn the midnight oil I can get one made sooner. I already have a design in the works that would use a SS ball thrust bearing. I think i need minimum height so everything fits within length, but I'll measure my forestay eye to eye length today to get a better idea.

Thanks for all the help guys.
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Re: THinking of adding a furling Jib

Postby GreenLake » Mon Sep 10, 2018 2:31 pm

The 150% should be a sail you use when conditions are (and are likely to remain) moderate.
For all other cases, you should start with a 100% standard jib.

The reason is that a 150% will be overpowered in many conditions and once you furl it, your DS will sail poorly. They do better with the jib up. In (predictably) light airs, I bet you'll really benefit from having a larger jib, though.

There are larger sails that people use with furlers, but the ones that have been discussed here in the past where more like a code zero than a standard genua. One member here flies his on a furler mounted on a short sprit. It's flown ahead of the forestay, so he can raise a regular jib after furling his bigger sail. (Obviously there must be some furler that can handle his sail, but I don't know without reading the old post whether it's a full 150%).

Check out these threads: "Doyle Universal Power Sail" (the link goes to a part of that thread that has pictures) and "Another UPS".
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Re: THinking of adding a furling Jib

Postby 109jb » Tue Sep 11, 2018 12:52 am

Yeah, I need to get a standard jib at some time but for now the 150 genoa is all I have.

I'm wondering if this would be possible?

Install a short permanent bowsprit and install a block for a halyard on the mast where the upper forestay attachment is. Then use the 150 genoa with furling setup at this location as the forestay as we have been talking about.

Then, buy a standard size jib. If I need to reduce sail size then furl the big genoa, attach the standard jib to the stock locations at the stock stem plate and stock halyard and hoist the standard jib. Doing it this way would mean the standard jib would have to fly un-hanked. I would also wind up with 2 jib halyards. One would be used all the time with the furler as the forestay. I could of course start off with the standard jib and use it as the forestay as well.

What do you think of this idea?

I'm guessing I would have to insure the standard jib has a wire in the luff. I just about bought a used standard jib that didn't have a wire, and had only luff tape reinforcement at the luff. It was a used Doyle sail and it turned out the asking price was higher than a brand new jib from Intensity Sails. Not knowing the difference in brand quality I passed on it. I'm guessing a sail like that could not fly un-hanked. Is this what you guys would think?
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Re: THinking of adding a furling Jib

Postby jalmeida51 » Tue Sep 11, 2018 9:19 pm

I have a set of Intensity sails that came with the boat. You won't win races with them but who cares if you just day sail. The jib comes with luff wire, hanks, tell tales. Sometimes I see them for sale on e bay brand new. I guess their loft in R.I. has too many in stock. Not all the time on e bay. My jib is hanked on to the fore stay. It helps controlling it when I drop it. I use a downhaul on the jib. Not sure how well it will work with not using hanks on the jib when dropping it. Might get wet? Of course Doyle makes a better sail than Intensity but you can buy 3 suits of sails for the price of 1 suite of Doyle's. Intensity makes their sails in China. Not using hanks, you need a luff wire. good luck with your project, John
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