Originally Posted by Exile
No, your response was helpful -- thanks. My rope
tails & splices, however, definitely do take some of the load. There is only rope
going around the winches and I can't see how it would be feasible or safe to wrap wire around the winches even if I could. I also have wire going into the sheaves at the masthead. Not saying you may be wrong, just that this is how it's currently configured on my boat (by the PO), for better or worse.
For this & reasons of unknown age, I'm inclined to swap out the entire halyards with only rope. I had planned on just using Staset-X or maybe VPC in the same diameter as the rope portion of the existing halyards but Stumble's comments re: Dyneema/Spectra seem intriguing. Being a cruising boat, I would not be inclined to go fancy unless it was cost-effective.
Thanks again for the response. This is a task that's moving itself up onto my "A" list.
There area number of issues that need to be addressed, but generally if you have wire, go to the same size dyneema
. They are roughly equivalent in strength and stretch (the dyneema
is generally a tad better in both), and for a halyard
strength is almost never the critical factor, stretch it. Most halyards are carried at less than a few hundred pounds of load, and almost never more than 1,000lbs.
It is actually better to use an oversized sheave than a 'properly' sized one. Proper size here just means it meats the 8:1 ratio recomended for all line, bigger is always fine.
For clutches, either have your rigger, or learn to do it yourself (splicing amsteel is rediculously easy btw) do two things. The first is to bury a piece of bulking line in the core
. I typically use a 2 foot leingth of 1/8 amsteel for larger sized lines. When tapered properly this won't effect strength at all. But allows you to use small line with larger clutches.
If you still need more bulk, you can cover this area with a cover. Again a very easy splice to do. Depending on application figure on 2-3 feet of cover right at the clutch
The easier way to do this, but somewhat more expensive is to buy endurabraid, which is a dyneema core
with a poly cover. You strip the cover back so 1/3 of the line is only exposed core, 1/3 is both cover and core, and 1/3 is just cover. This allows you to have strength where needed, the cover to pull on when loads are light, and minimum line up the rig. This is very typical on race
boats, and does allow you to end for end it later.
As for dyneema, it is
1) the most abrasion resist line made, except for metal wire.
2) the most UV stable line made
3) the strongest
4) has similar stretch to wire
5) doesn't absorb water
It has been used regularly for standing rigging
, and running rigging
for years. And because it has so many industrial uses, is surprisingly inexpensive.