Jib Halyard Replacement

[grantmc 59]

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

[raz88 96]

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.

[Island Time 1,214]

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  

[Dambo 44]

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?

[Tim C 23]

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.

[grantmc 59]

Thanks heaps for all the thoughts and suggestions. 

[rossd 16]

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.    

[ballystick 72]

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.

[rossd 16]

That prestretched polyester might be a cheap way to go

[John B 106]

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!

[rossd 16]

John B ,so you mean there is a harder  cover on the top 11 metres and a softer one on the part that is handled . But the entire line is still 10 mm diam.

[John B 106]

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."

[Tim C 23]

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.

[wheels 543]

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.