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Jib Halyard Replacement


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Is an old style halyard, (pulling up a hanked on sail) that needs replacement. It is a combination wire rope at bow spliced to braid about halfway.  

Why are jib halyards made this way? Is it still common practice?

 

Is replacing with spectra a valid alternative? Would the old sheave get quickly buggered with spectra? The mast head sheave of course is quite narrow because it only handles the wire.

 

Thanks

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I'm no expert, but my understanding is the risk with going to spectra is not so much what the spectra might do to the sheave, but what the sheave might do to the spectra.  If the old wire setup has grooved the sheave it could cut/chafe through the spectra.

 

I know of people who have changed to spectra and stuck with their old sheave from their wire setup with no issues.  The sheave being narrow isn't really a problem, as spectra etc are still strong in small sizes.  If your halyard terminates on a jammer check your jammer will still work with the narrower line, although a smart rigger might be able to add a sheath or poke an extra line down the core where it goes through the jammer to bump it up a size.

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Raz has it right. You need to either change the sheave, or make sure it is ok for the spectra - no burrs, no sharp edges, If there are any, you can take the sheave out and clean it up, or if it is a common size, replace it. Make sure that the jammers and the winch can deal with the new halyard dia...

Wire/rope halyards were used to minimise stretch, no need for them any more with modern fibres :-) 

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Why are jib halyards made this way? Is it still common practice?

As IT says, to lower the elongation and Yes surprisingly we still make more than I would have expected.

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I did check the sheaves on the two boats that I've replaced wire-rope with spectra - nil issues with the blocks despite on one of them appearing to be the 40 year old originals.  Nil issues, fraying, pinching, or pulling of the cord seen.  

 

The concerns I've seen have largely been published on websites and forums overseas.  Perhaps older or simply different materials used in the manufactoring of the blocks elsewhere in the world?

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The concerns I've seen have largely been published on websites and forums overseas.  Perhaps older or simply different materials used in the manufactoring of the blocks elsewhere in the world?

A lot of the concerns, myths, old fella stories and things like that people still use and believe to be true today just aren't. We see it constantly where people bring up things that were true but back in the day and not so in todays world. So I'd say Dambo is absolutely correct in his caution and why.

 

Talk anchoring and you are often stepping back into the 70's if not further back.

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At the risk of having KM jump up and down, I'd recommend Vectran over Spectra. Similar price, but way less creep when under load for hours, such as a long race.

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I thought replacing my main halyard and pensioning the old one to the main sheet would be a simple and cheap operation, sadly mistaken. Like $200!  I measured my ancient halyards and they are 13 mm, I looked up Donaghies line size chart and main halyard for 26 to 33 foot yacht is 8 to 10mm .. 8mm!! my stiff old fingers would hardly get enough grip on that to pull a skin off a rice pudding especially after handling a line the size of a small eel. And this is the problem , between strength and some thing nice to get hold of.To get some thing without stretch in  12mm besides costing a fortune can take 10 tonnes!!  From a load bases I think 6mm would do it if not 4mm. So wouldnt the logical thing be to go back to the old type system and splice some stretchy nice fat cheap 12mm to some 6mm fancy stuff and have the best of both worlds.    

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I think many people cover the thinner strong cores with nice light and tough covers, quite often old ropes that have sections of lightly worn sections, the covers only need to be in areas handled by hand, winch and clutch.

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http://www.armare.it/en/linee-prodotti/cruising-line/prodotto/speedplus

http://www.armare.it/en/linee-prodotti/cruising-line/prodotto/star

https://www.donaghys.com/rope-and-cordage/products/leisure-marine/high-performance/superspeed

 

The way each company measure and report their break loads differ considerably.

 

2 Spectra cored which gives near dyneema like elasticity but a lot cheaper. One has a std polyester cover, the other a polyester/cordura cover (better wear resistance and anti-slip). The other is a pre stretched polyester double braid. All are in the gap between the usual polyesters and dyneemas.

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When I did this with my main halyard last year Doyles advised and made up for me a 10 mm halyard with a quite hard cover fitted over the top 11 odd metres. 10 mm was the miniumum I wanted to go to because of handling and there's enough cover so that with all reefs in there's still extra chafe protection.

I think its worth doing, even in the old days it was common practice to 'shift the nip' of any line through a sheave/ block etc. Not so easy with set splices , so the cover is useful in prolonging life.

 

Those old rope to wire halyards and runners seem to last forever!

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Near enough Ross. Its 10 mm spectra or vectran ( can't remember) which already has a cover standard. On top of that there's another harder ( to the feel) cover sewn on for chafe. might be a poly of some sort , quite plastic feeling. This is a main halyard so the nip / chafe points are over three general spots, full hoist and two reefs, and any trim / tension variation within that.

I like it. Sail is about 400 ish feet and while 12 mm would be nicer, I'm satisfied with the 10 for not so young hands.

 

From Doyles website

 

" Chafe guard for high load areas is no problem with a range of options including Polyester/Spectra or Technora chafe guard available."

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It'll be Vectran, not spectra.

The chafe sleeve will be dyneema.

 

Bit surprised to hear vectran is still being recommended for halyards considering the options available.

 

DO NOT...... DO NOT let UV get anywhere near the Vectran. The US military and ISIS are far better mates than vectran and UV are.

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Come on Knot Me, expand on this!

Convince me that Spectra/Dyneema doesn't creep like it used to. I've been way happier with my Vectran halyard than the last Spectra one. The latter seemed to grow 150mm in a Coastal classic. 

So what's changed?

A good thread here 

It'll be Vectran, not spectra.

The chafe sleeve will be dyneema.

 

Bit surprised to hear vectran is still being recommended for halyards considering the options available.

 

DO NOT...... DO NOT let UV get anywhere near the Vectran. The US military and ISIS are far better mates than vectran and UV are.

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I won't pretend to know more about line than Km does, I was constantly learning from him as I tested line.
I found that in all our testing, the actual material a line is made from is not what creeps(leaving aside normal elasticity of the particular fibre). It is the way in which the weave creeps as it pulls tight. So the lines that have fibers running straight have less "creep", because all the fibres are straight and only elasticity has any affect. Hence pre stretched lines. So importantly, how well that line was woven in the first place, will affect how much creep the line has. And that is what tends to be the greatest point of difference between a top quality line against a cheaper one. Although price does not always tell you that, apart from the fact that the tighter a line is woven, the more fibre there is going to be per metre of line. 

Taking that one step further, the sheath is a protector. Most often made in a different material than the inner. Also woven in a different way. So as the inner is stretched and pulls tight it "shrinks" in diameter and the outer sheath is now a slightly different diameter (larger) than the inner. More noticeable in poorer quality lines. So the outer wears faster as clutches do not grab the line well and the outer sheath takes a greater load that which it was designed to. And any movement under extreme loads, results in heat and one thing that always stunned me was how fibre melted due to the heat. Heat damage due to high loads tends to be the main cause of failure.

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DM20 has the same creep specs as Vectran. There is also the SK99 which is hugely stronger so as the load you will put on it, as a % of it's break load, is lower there is less creep action.

 

As the DM20 is lighter (so lite it floats) it has to be better from that angle alone. It took us a bit to get some as all the early production went direct to a few selected fibre rigging guys to used it to replace the Vectran they have traditionally been using.

 

Then there is the UV issues. It's recently reared it's head in a biggish way in backstays, plus a few other things, that have been failing around the place, most of which are Vectran. It's appearing there is a time issue with the material and that is made worse by UV. Hence the DO NOT let UV get near it.

 

Coincidently while writing this I had a call about a backstay becoming naked and it has a goldie material inside, vectran or kevlar, the owner would like recovered. That is the second one in 2 days as the same discussion was had with another boat on Saturday.

 

We've been doing some Vectran testing and tested some that was looked after and well coated. The load lose after 4 years is not just noticeable, it's gobsmakingly massive. Note 'coated' not 'covered' as in coated with one of the common rope paints available. We also tested some Vectran that has sat naked uncoated or covered for near on 2 years. It's rooted.

 

So it seem there has come a point where the coverings on Vectrans are starting to break down from use, sun and so on which is leading to UV being able to get at the Vectran inside and killing that as well. Also the coatings may not have the UV protection as well as is possibly suggested, whether that's all of them or just some of them isn't clear, or the coatings just aren't doing it on the Vectran fibre.

 

The fibre rigging mobs use Vectran a lot but it is seriously well buried below other materials so not a large issue I'd expect. Most are/have moved to the DM20 instead now so the issues just won't be one for them.

 

2 of the ropes we tested we also had some of the original as well so we got good data on before and after. The unused never seen UV rope broke at over 4000kg, 3 to 4 seasons later the used ones were under 500kg yet perfectly fine during visual inspection. It wasn't until the load checking we started to see undies changing colour and aroma.

 

But for us mortals who have any the best thing is to minimise the chance of any Vectran and UV meeting or you risk very large strength degradation reasonably quickly.

 

Spectra hasn't got creep in hand as much as Dyneema yet but they are back in the game and going hard so maybe we'll see them with a DM20 equivalent soon. The latest grade of Spectra is back in the game with the common Dyneemas...yet at a nicer price.

 

As ball park guide for interested parties on Dyneema -

SK60 - old school but still used by a few fringe mobs

SK65 - a small bit stronger than 60. came and went in no time, no idea why

SK75 - a nice bit stronger than SK60 with a bit less stretch and creep. Common as out there being the base grade for most manufacturers these days, it is also what Dynice (Dynex) is but now most mainstream manufacturers have moved onto SK78 so 75 will quietly fade away like the 40 and 60 have.

SK78 - about the same loads as SK75 but considerably less creep. This is the new base grade for progressive manufacturers now.

SK90 - Same creep as SK75 but about 10-12% stronger.

SK99 - round 20% stronger than 75/78 but with a motherload less creep.

 

DM20 - a HUGE amount less creep, approx 90% less, than SK75 but not quite as strong.

 

Vectran is pretty much SK75 but with the creep taken out.... but it is heavier than Dyneema and Spectras.

 

 

How would a Cat 1 Inspector tell is a Vectran is still good to go? Bar seeing it dry and crumbly, which I suspect probably would never happen as it would have failed by that stage, I'd be thinking they couldn't short of doing a load check. It's a bit like SS rigging, looks fine ... right up to the moment it fails. The curse of the modern age I suppose.

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