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Re: Untwisting jib sheets?
What's happened is that the twist of the individual yarns has slipped due to excess strain on the rope; and, as the rope repeatedly strains then relaxes then the entire rope also becomes cumulatively shorter (and a wee bit fatter) - called 'hysterisis' ... and all the individual yarns inside the rope are doing the same 'shorter and fatter as well as increasingly twisting'.
For a temporary fix: You can heat soak the rope in (not to exceed) 175°F water, then quickly strain it back to its original length. I quickly tie the hot rope between a tree and my trailer hitch and 'pull' with my vehicle, then let cool while its still 'stretched'. But, there will still be some twist remaining due to the residual 'shortening and fattening' of the small yarns. However, this rope in further application of high stress/strain will continue to get shorter / fatter / twisted. What you purchased is a highly unstable rope and most of the current boat stores sell it (hint: its the cheapest you can buy) !!!!!
The best solution is to purchase a more expensive grade of more stable line and the shortening and fattening and the ultimate 'twisting' will be much less. In the high grades of line such will probably be unnoticeable for years and years of 'heavy' service. You must realize however that any rope made from twisted yarns and used 'heavily' will eventually get fatter, shorter, twisted ... its just a matter of time and how many time that rope gets stretched out; the higher quality of the rope, the longer it takes.
Rx: buy a much higher grade of line which is stronger in breaking strength (even if its diameter is one or two 'sizes' smaller); and then, dont use it to anywhere near that breaking strength .... for less 'hysterisis': shortening/fattening/twisting that is residual after repeated episodes heavy stress/strain.
Last edited by RichH; 08-23-2014 at 09:57 AM.