Strange rope wear

Jodel

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After a winter with not too many storms on the Clyde my mooring lines have gone fluffy. Is this purely down to wear or is there some reaction between the rope and the rubber? The line underneath is the same rope.

IMG_5648.jpg
 

Rappey

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It looks like the outer sheath has been streched and then relaxed. I wonder if unwinding it then pulling would make it look normal again?
The wound fibres of the outer braid have completely untwisted . ?
 

SaltyC

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Abrasion? As the snubber comes under load it stretches and the rope slides up and down the snubber, probably twisting at the same time abrading the cover? I haven't noticed this on my 3 strand ropes around the snubbers, will check this week.
 

johnalison

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Yes. Abrasion. The surface of the rubber snubber is rough and even has letters stamped into it. This will abrade the rope over time.
I presume the rope rotates when the snubber is stretched for this to happen, though it is too early in the morning to get my head around the geometry. It’s not something I had thought about as I only use our snubbers for short-term mooring.
 

Leighb

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We had the same type of snubbers on our fixed mooring lines for about 15 years. The rope was 3 strand nylon though, and never showed any sign of abrasion wear. This was in a marina with the tide running through and often quite choppy if wind against tide. Maybe the “softer” braided rope is more prone to abrasion.
 

Jodel

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Thanks all. Abrasion seems to be the most likely. I'll have another look tomorrow when I go back to the boat.
 

rotrax

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As that type of rope has up to 14% stretch, one wonders if the snubber rubbers are needed. My 14mm eight plait mooring lines are still good five years after I made them up. Done at least 500 nights alongside.

I do have heavier - but still stretchy - winter only lines for when alongside November till May.
 

Stemar

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As that type of rope has up to 14% stretch, one wonders if the snubber rubbers are needed.
The trick is to set up the lines so they are as long as possible. I run the breast lines to the outboard cleats on my cat, which gives around five metres of stretchiness, and they never snub hard. I see others with maybe a couple of feet of line and I wonder about the stresses involved when a big wake comes in.
 

johnalison

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The trick is to set up the lines so they are as long as possible. I run the breast lines to the outboard cleats on my cat, which gives around five metres of stretchiness, and they never snub hard. I see others with maybe a couple of feet of line and I wonder about the stresses involved when a big wake comes in.
That’s all very well but the average finger berth in a marina only gives a run from the bow to the corner of the berth, maybe eight feet if you’re lucky, and in my case even shorter at the stern. You can only achieve long lines with an alongside berth, and certainly not with breast lines when rafting, making snubbers a great boon in many cases.
 
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