Originally Posted by NewEnglander
I appreciate the response. So it's your opinion that most cruisers have overly heavy halyards? By what margin?
It very much depends... If you have halyard locks then pretty much any boat in the world could get away with 1/8" dyneema
since the only load the halyard carries is the weight of the sail as it is hoisted. If you aren't using locks, then it is a much more difficult question.
First you need to understand the amount of load on the line. This SHOULD be the starting point for any line selection problem, but most sailors have no idea how much load is actually present, and drastically overestimate the amount of load.
So let's start with what we know, and work backwards based on the deck hardware
on a normal 40' cruising boat.
Winch -Lewmar 44ST - MBL of 2,500lbs
-Spinlock Zr1015 - MBL 3,000lbs
base block - Harken
1986 - MBL 1500lbs
So just from our deck gear
that hasn't failed, we know that the maximum load can't be any higher than 1500lbs or deck gear
would already be failing. And could never be above 3000lbs or everything would start falling apart. However a very standard halyard recommendation for a 40' cruiser halyard would be 1/2" sta-set x with a MBL of 10,000lbs. But I have seen recomendations go as high as 5/8" sta-set with a MBL of 15,000lbs.
Chainplates as an example are typically specced at a 5:1 safety
margin, so why in gods name are cruisers running 10:1 on halyards. I really don't know, and have never understood it.
If we work with worst case scenario numbers and assumed a working load of 1,500 lbs, and a very conservative 5:1 safety
margin that means we really need a line with a MBL of 7,500lbs, somewhere between half and 75% the strength of what can typically be found. So what line does this mean for our selection?
8mm endurabraid has a MBL of 8,100lbs
1/4" amsteel blue has a MBL of 8,600lbs
Either of these would be vastly superior than lugging around all that weight, water
absorption, and cost of oversized lines.
So how much would each of these lines cost... Let's assume that our hypothetical 40' boat needs 100' of line for a halyard...
1/4 amsteel ...$168......1.60lbs