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#1
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![]() A Question: What's the deal with wire halyards?
I've just gotten the mast out of my boat. one of the things i was looking to do was replace the existing wire (rope tailed) halyards with modern rope halyards. Of course, i've found that the masthead sheavebox is far too narrow to accomodate proper rope sheaves. My options seem to be to either completely re-build the masthead, or put in new wire/rope halyards. Given the complexity of the former (especially given my weird very-tapered, fiberglass(!) mast), i'm thinking of juist refreshing the sheaves aloft and putting in new halyards. It's a dandy excuse to practice up on wire/rope splices anyways... What is the problem with wire halyards? i can see there being an issue with weight, and with fish-hooks as the wire degrades, and increased chafing on the mast/spreaders, but... If good attention is paid to fair leads, maintenance, and such, what is the big drawback, if any? What am i missing here? |
#2
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![]() Hi there,
If you do an analysis of load/stretch for wire and same-strength High-Modulus (HM) rope, I believe you'll find them to perform about the same. In my experience, people have fled from wire halyards for mostly avoidable reasons. For instance, if the halyard is cut so that the wire, either bare or inside the rope, is on the winch at full hoist, then rope, winch, and wire get mangled, plus there is a very strong tendency for the halyard to leap off the winch when you are slacking. Bad. And the reason people cut halyards like this? Most likely because they don't trust that tail splice, so want to get it past the winch before the load comes on. A good splice is, of course, at around 90% efficiency,so by solving a non-existent problem, they create a real one. As you noted, any chafing issue can be solved with appropriate fairleads. The meathooks at the sheaves cannot be prevented entirely, but they can be greatly delayed with the biggest-radius sheaves that will fit in the mast, along with a V-section for the wire to lie in, instead of the traditional notch profile. And of course the right size rope ó not so large that it will meathook soonest, not so small that it will fatigue soonest ó will make a difference. So that leaves lightness, and HM is a clear winner here. Which is why we often use a rope-to-rope splice, with (covered) HM spliced into a fat Dacron tail. The tail has to be small enough to crowd through the masthead (unless the halyard runs aft, which buys you some extra room), and the rope is not much bigger than the same strength wire. Fair leads, Brion Toss |
#3
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![]() Well, yay to wire halyards indeed! My biggest reason to want to go to (non-tapered) rope is so that my spare (i have three masthead sheaves) could be used either fore or aft. As currently set up, the spare is set up aft (the rope tail is forward), which is how i'll use use it.
The sheaves are narrow (5/16" for the two outside sheaves, 7/16" for the center), but are about 8" in diameter, and spin smoothly in their boxes. They are aluminium, and need to be at least re-dressed, and at most simply replaced... But i now think i'll stick with the wire! The existing wire halyards are 3/16"; i may upsize the main halyard, but then again, perhaps it doesn't need it... Last edited by osteoderm : 09-01-2006 at 05:36 PM. |
#4
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![]() What are the advantages of sticking with wire? Longevity?
It just seems like HM fibers are a lot easier to deal with, both while splicing and putting up the rigging, but also in use...no fears of meat hooks! ...Just curious, that's all. love nick |
#5
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#6
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![]() Nick,
i'm all for (otherwise exotic) rope-rope slices and fancy lines, but the trouble is with my masthead sheave box. The center sheave is only 7/16" wide, while the two side sheaves are only 5/16"! The existing wire halyards are 3/16". i hate cramming the largest possible line through any block; while a 3/8" main halyard would probably run through, i'd rather keep it to 5/16" or 1/4". Having said that, i'll probably go with a 3/8" rope tail on the main halyard, because the tail WILL run completely through in a pinch. As for the side sheaves (which will hold the jib halyard and a spare), i'm definately not keen to run anything larger than 1/4", and then only if i can be sure that the lead is utterly perfect. 3/16" wire will run with room to spare, and will be subject to less chafe; NOT because of being wire, but because the smaller size allows a little more wiggle-room before the halyard makes contact with the cheeks. There's some amazing HM line out there, of which i'm a huge fan, but there doesn't seem to be anything (i'm still researching) that is a neat replacement for 3/16" wire running in 5/16" sheaves... |
#7
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![]() Hi again,
First, the rope-to-rope splice isn't in any current book, but will be in a future one. Next, the sheaves here are industrial-size, relative to 3/16", or even 1/4" wire rope, so meathooks should be long-deferred. And finally, uncovered HM rope would do just fine, except it would likely be more subject to chafe than wire. Fair leads, Brion Toss |
#8
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![]() Hi Brion-
I am very adept at the typical uncovered HM interconnecting center splice -- uncovered HM spliced to a fat dacron tail. Is this splice done is a similar way? Do you design to not load the core splice? I assume you do not tuck the fat tail cover into the covered HM -- just whip it down -- HM covers are typically very tight and tightly woven. I understand the efficiecy of just documenting this once, but a few details wouldn't hurt, would it? 8-) Bob |
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