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I'd rather be sailing
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Discussion Starter · #1 ·
I have a Harken Mk IV Unit 2 furler. For those of you with this furler, you know how wonderful the included line is (note intended sarcasm). I'm looking at replacing it with 3/8" XLS yacht braid as opposed to using 5/16" line (which is what's standard). The 5/16" is hard to grip. Other than the fact that this will create more bulk on the drum, are there any other ramifications?

Also, with regards to line choice, I was going with the Samson XLS since it's fairly easy on the hands. Would anyone suggest going with a higher tech, less stretchy line? While I'll use a higher tech line for halyards, I don't love the feel of it going through my hands...
 

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Labatt-

Going up a line size might not be an option, since the drum only has a finite amount of line it can carry and making it a larger diameter may prevent it from holding enough line. What you should probably do is stay at the 5/16" size and get a jacket put on the tail end, which you handle, to make it easier to grip.

Two other options are either removing the core or the jacket from the lead end of the line, where it wraps around the drum, and using a larger line. Using a higher tech line with a stronger core is a good idea, especially if you want to keep the diameter of the line wrapping around the drum down in size. Having a bit extra strength in your furling line is never a bad idea, especially when the crappy weather and heavier winds hit.
 

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Seattle Sailor
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I replaced my 1/4" with 5/16" on an older furling unit and didn't have any problems. It seemed like the 5/16" was really not much bigger than the older 1/4" line anyway. As long as there is a little room on the drum when the sail is unfurled, I can't see any reason not to go to a slightly larger line.
 

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My furler is actually loaded with a wire/rope halyard, which gives it a very small buildup of steel cable on the drum and a larger diameter line on the end I handle. You can get a lot of strength with very little load on your furler drum!
 

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My furler is actually loaded with a wire/rope halyard, which gives it a very small buildup of steel cable on the drum and a larger diameter line on the end I handle. You can get a lot of strength with very little load on your furler drum!
That's interesting - is your furling hardware all capable of handling wire? Another thought is that wire-to-rope splices are not necessarily designed to be load-bearing and it sounds like you're using it as such.
 

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I see no reason why it shouldn't work as long as there's plenty of room, keeping in mind that it might not spool up neatly over time. That said, if it got so much load that it's hard on the hands, how about wrapping it on a winch and either grinding it in, or if going out, use the winch to control it. Sdog's idea to add an extra cover to smaller line or strip larger line is ingenious.
 

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QS192-

While I'd love to take credit for the idea... that's been a pretty common practice among racers I know... :) My favorite setup was a boat that had a furler with 1/4" spectra line for the furling line, and had added a polyester cover to the tail end for ease of handling... so it was about 3/8" on the cockpit end. :) The 1/4" spectra line was more than strong enough to handle any loads on the furler.
 

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S/V Loon
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Large line yields more mechanical advantage

My new North sail has a 'rope luff' and as a result it forms a larger wrap around the luff as it rolls up. Because of this, I'm now having a devil of a time getting the thing furled if the wind is blowing, I pretty much have to go off the wind to reduce the load.

Plus my back really does not like the twisting pull I seem to use on the furler line.

I was also thinking about an increase in line size, or else using a longer line and leaving more wrapped when the sail is all the way out,, so the effective diameter of the drum is larger when I'm trying to get the sail in. This also would make it easier to furl.

Does this seem like a reasonable approach?
 

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Telstar 28
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My new North sail has a 'rope luff' and as a result it forms a larger wrap around the luff as it rolls up. Because of this, I'm now having a devil of a time getting the thing furled if the wind is blowing, I pretty much have to go off the wind to reduce the load.
The rope luff is probably there to help the sail keep better shape when reefed.

Plus my back really does not like the twisting pull I seem to use on the furler line.
Should probably work out to strengthen those muscles before you injure yourself.

I was also thinking about an increase in line size, or else using a longer line and leaving more wrapped when the sail is all the way out,, so the effective diameter of the drum is larger when I'm trying to get the sail in. This also would make it easier to furl.

Does this seem like a reasonable approach?
Not a bad idea, but there's a limit to how much line you can have on the drum before you've got too much line on it for sail to unfurl completely. You should generally have two-to-three wraps on the drum when it is fully furled with two-to-three wraps of halyard around the sail. This helps prevent problems with the load on the furling line causing the drum to separate and with the sail unfurling in higher winds. :)
 

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Thanks Courtney.
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Line size is certainly going to be an issue. Make sure your drum can handle the extra line you are thinking of loading.

Padean- 5/16" would be exactly 1/16" larger than 1/4", or 25%.

I think I would avoid the use of XLS. I like Sampon line most of the time and have used it a lot, the XLS (Xtra Low Stretch) tends to kink easily and might hinder your furling ability.
 

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Use a winch

The jam cleat for my genoa furler line is mounted near the port side jib-sheet winch, so it's easy to simply slip the bitter end of the furler around. Works great.
I mean, it's not like you're gonna use the sheet if you're furling up the sail! ;)
 

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Yes, but that is 25% in diameter, but the problem isn't diameter, but area... a 1/4" line has a cross section of 0.0490625 sq. inches, and 5/16" line has a cross section of 0.0766016 sq. inches, or 156.25% the cross-section... so that's the real problem. :)

Line size is certainly going to be an issue. Make sure your drum can handle the extra line you are thinking of loading.

Padean- 5/16" would be exactly 1/16" larger than 1/4", or 25%.

I think I would avoid the use of XLS. I like Sampon line most of the time and have used it a lot, the XLS (Xtra Low Stretch) tends to kink easily and might hinder your furling ability.
 

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Thanks Courtney.
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Yes, but that is 25% in diameter, but the problem isn't diameter, but area... a 1/4" line has a cross section of 0.0490625 sq. inches, and 5/16" line has a cross section of 0.0766016 sq. inches, or 156.25% the cross-section... so that's the real problem. :)
I beg to differ. The cross section of the line is not the issue as it is a 2D measurement. The capacity of the drum is is going to to be filled by the 3D diameter of the line. If the sizing of the furler was borderline then the increased diameter of the line could cause it to fill to the point that overrides and jams become more common. If the furler installed was up-sized for the given boat/sail then none of this will matter and he can likely put on whatever line he chooses.
 

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T34C-

How do you measure the volume of a cylinder... by its diameter—NO...you measure it by the length of the rope times its cross section. The cross section is far more important when calculating volume taken up, and the drum has a limited volume.

BTW, there's no such thing as a 3D diameter...

TaylorC-

Yes, using a winch on a furling line is generally a bad idea.. .if the furling system has so much resistance, it is usually a sign that something is wrong.
 

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I'd rather be sailing
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Discussion Starter · #16 ·
Just to stop conjecture... I talked to Harken and they did the math... based on the length of my boat, 3/8" line will fit just fine on the furler drum when all out... T34 - if you don't like XLS for this application, do you have a line you'd like better? I'd prefer to go with a line that I don't have to add a cover to or de-core - that lies well and is easy on the hands, right out of the box. This is why I was thinking XLS... Thoughts?
 

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ASA and PSIA Instructor
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The jam cleat for my genoa furler line is mounted near the port side jib-sheet winch, so it's easy to simply slip the bitter end of the furler around. Works great.
I mean, it's not like you're gonna use the sheet if you're furling up the sail! ;)
My opinion is you are looking for trouble if you secure a furling line with a jam cleat. If the line works lose in the middle of a strong breeze, you will be out at least the sail. You should secure the furling line to a horn cleat only.
 

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I'd agree with SF... you really need to use a proper cleat hitch for a furling line...

What I'm planning on doing this winter is running the two furling lines—screacher and geona—through a pair of line clutches... but they'll still be cleated off on regular horn cleats as well. The clutches are just to make furling, reefing and unfurling the sail easier. :)
 

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Thanks Courtney.
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Just to stop conjecture... I talked to Harken and they did the math... based on the length of my boat, 3/8" line will fit just fine on the furler drum when all out... T34 - if you don't like XLS for this application, do you have a line you'd like better? I'd prefer to go with a line that I don't have to add a cover to or de-core - that lies well and is easy on the hands, right out of the box. This is why I was thinking XLS... Thoughts?
I would say New England's Sta-Set X is probably comparable to XLS, but doesn't tend to kink as much. (standing by for someone to disagree;) )

dog- You said it yourself you are looking for a VOLUME measurment not just the width of the line. the drum has upper and lower stops as well as as an outer extreame. And no there isn't a 3D diameter, but there is a difference between the diameter of a 2D object and a 3D object. The diameter of a circle has less mass than the diameter of a cylinder. In this case both the drum and the line are cylinders, not just circles.
BTW- Speaking of volume, are you buying clutches by the gross now? YOu gotta be running out of deck space soon.
 

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I would say New England's Sta-Set X is probably comparable to XLS, but doesn't tend to kink as much. (standing by for someone to disagree;) )
StaSetX is pretty stiff, and I'd wonder about it as a furling line for that reason...other than that it's a pretty good line.

dog- You said it yourself you are looking for a VOLUME measurment not just the width of the line. the drum has upper and lower stops as well as as an outer extreame. And no there isn't a 3D diameter, but there is a difference between the diameter of a 2D object and a 3D object. The diameter of a circle has less mass than the diameter of a cylinder. In this case both the drum and the line are cylinders, not just circles.
You must have learned the new math... diameters are measurements in distance, not in mass...The important thing is that a 25% increase in diameter is over a 56% increase in volume... :) which means only about 2/3's the length of line will fit in the same volume... 3 x 1 is about the same as 2 x 1.56... :D

BTW- Speaking of volume, are you buying clutches by the gross now? YOu gotta be running out of deck space soon.
Nope.. this isn't going on the cabin top..it's going on the coaming, where the furling lines are... Didn't buy it anyway... got it as a stocking stuffer last year, and since it was for too small a diameter line for my halyards project, but the right size for the furling lines, I didn't swap it for a larger diameter line model. Besides, I already had all the line clutches I needed at that point. :)
 
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