We are trying the recycling of climbing ropes from indoor climbing walls. They tend to be 'short', because artificial walls are not very high, so think 12m-14m, but there are higher walls, so longer ropes. Climbing ropes are 11mm, a double braid, and have around 30%-35% elasticity (they are specifically made to be 'elastic'). Splicing braid is too complicated for me and I simply use a 'scaffold' (I think that's the term)
knot onto a bow shackle and then a chain hook. If any of you splicers are passing through
Sydney, I'd welcome a lesson (one double braid splice took me about 4 hours!). Being a cat we have a
bridle and run the ropes through turning blocks on each bow, then down the side decks to the transom
mooring cleats. It all works quite well, but have not tried the climbing
rope over 30
knot gusts. We use hose pipe on chafe areas. We find one side then the other takes all the load - because we still swing. So no good thinking you can halve the size because you have 2 ropes - does not
work quite like that.
The big advantage, we picked up 6 lengths for free.
Climbing ropes are retired on basis of time, wear on the outer casing of if they have taken a big fall. (Some) climbing walls simply throw them out (ring and ask!). I'm guessing they would make good springs as
mooring lines.
We have tried rubber mooring compensators - they only
work in low
wind ranges, once the
wind gets up (when you need a bit of elasticity) they are at full stretch (so a waste of time,
money and they are heavy for what they do). I'd guess that rubber mooring compensators become redundant at the same time as you
lift all the chain off the seabed, and that takes surprisingly little wind (30m of 8mm chain at 5:1 lifts under a load of about 80kg, in air - so less in
water, say 70kg approx). Nylon works almost upto its break point and if you are getting near that its pretty breezy (and I doubt many will experience that level of wind). But any cordage degrades, so carry spares - we had a half inch
bridle, hawser laid nylon snap after a couple of years use.
In many
anchorages you cannot use mixed chain and nylon rodes, the nylon can wear out overnight (bits of
coral rubble are very aggressive), safer to use all chain and a snubber or bridle.
J