wire vs. rope

[charrette]

i am in the process of reworking my existing split backstay which is fixed with a means to adjust the tension. i can't use the pincher style setup because the wire runs through my bimini so i was going to install a runner block at the split and run 1/4" 7x19 wire from one side to a tackle system on the other. a local rigger suggested that i use high strength rope instead which would be lighter and run better through the blocks. he suggested a 1/4" 12 strand single braid line. either v12 or endura 12 by new england ropes or amsteel by samson.

any thoughts on which line to use, what type of eye splice would be the strongest for 12 strand single braid and should a thimble be used at the eye splices?
thanks

[Brion Toss]

Hello,
V-12, or a covered version of Vectran, for UV, would be my choice. Thimbles would be nice, though a Ring Hitch would also work. Be sure you cut the length with compensation for constructional stretch (about 20%) and splice takeup (varies with diameter) for a good fit.
Fair leads,
Brion Toss

[NickfromWI]

Brion, what do you mean by "constructional stretch?"

love
nick

[Bob Pingel]

To quote the master, "constructional stretch is a permanent elongation that results from the strands in a new piece of wire settling into place when the wire is first put into use". Of course, this quote refers to wire, but the same behavior applies to cordage.

I think there may be a typo in that 20%, maybe 2%?

I also have seen constructional stretch somewhat recover in cordage, I'd think wire would do the same thing but to a lesser degree. I have customers that will pretension halyards before each race to take up any elasticity.

Bob