Degradation of nylon

American DIY sailing magazine finds that old x 3 strand nylon rope degrades under UV light after a decade or so in contrast use to tie up a vessel. Bowline and eye splices significantly weaken old rope.

Click bait.

Unoriginal reporting and investigation, it is not as if folks don't already know this.
 
No surprise about the fact that old rope is weaker than new, but how much weaker is still useful to know. Assume 1/4 of the new strength, and you've at least got an idea if those lines are still up to the job.

I wouldn't say the article was useless. To me, at least. it's of far more interest - and use - than interminable reviews of boats I can't afford and wouldn't buy if I could.
 
American DIY sailing magazine finds that old x 3 strand nylon rope degrades under UV light after a decade or so in contrast use to tie up a vessel. Bowline and eye splices significantly weaken old rope.

Click bait.

Unoriginal reporting and investigation, it is not as if folks don't already know this.
This forum has a catholic membership, some old salts like you who know everything and newer members who are starting on the education ladder. My previous post on MOBs and tethers etc was also thought of as click bait by one - but I found the MAIB report - go over and you have a 50/50 chance of survival - sobering - and I too also thought I knew everything and could not be shocked.

Of nylon rope degradation - there is now increased use of nylon as a snubber - we keep our snubbers permanently installed on deck and some long term cruisers spend much time at anchor. Those snubbers will fail through UV degradation, and /or abrasion (the degradation can be unseen) - carry spares.

We all become complacent - though might not admit to same.

BUT - I like to cater for new members - as old salts know it all already - which makes me wonder why they are forum members if they object to supporting the neophyte.

Jonathan
 
I doubt that tensile strength is the failure mode for most dock lines. Chaff/abrasion seems a much more likely cause of failure. The article is far from a scientific analysis. If I have a 10 year old line that lives in a locker 360 days of the year how does it compare to one the has had the sort of use these ropes saw. I don't use Nylon for dock lines so how do other materials fair with age? Do all Nylon ropes age the same way in the sun (and how does Chesapeke bay compare to rainy Scotland)? Does octoplait do better/worse than 3 stand etc. Small studies are interesting, but the headline describes it as the ultimate endurance test and the article says never [previously] been accurately quantified. So I think its reasonable for me to expect some decent science and meaningful testing.

Which is almost as poor as the MAIB "50%" of MOB's die implication...
 
What happened to the time-honoured practice of using old jib sheets as dock lines? Nelson will be turning in is grave. (Horatio, not Mandela)
 
My dock lines are polyester but I keep nylon lines in a locker for use when cruising away from home, because they are 'kinder' to the boat and less prone to squeaking. I would not expect them to deteriorate significantly over a few years.
 
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