Mooring lines - nylon, multifilament, poly etc..

[Sheerline]

I know nylon is generally the recommended material for mooring/dock lines.

But my local swindlery catalogue lists various mooring/docking lines as polypropylene, polyethylene, double braided multifilament, high tenacity multifilament, low tenacity multifilament, high level PE resins...

Which is which? Some are double the price for what appears to be the same thing.

I'm looking to use them when I'm rafted up with other boats - a bit of elasticity seems to work well.

Any advice?

 

[spinny]

Nylon.
Protect with good chaffing pieces where it runs over edges. Nylon can stretch up to about 45% before it parts, but you don't want to get anywhere near that figure. 15% to 20% is the recommended safety margin.

 

[Sheerline]

I think they're all nylons.

But do any have any advantages?

 

[PetiteFleur]

Don't use Polypropylene - it suffers badly from UV degradation and is also has considerably less breaking load than Nylon or Polyester. Nylon is usually recommended as it is 'stretchy'. Polythene is very hard, usually orange in colour, again not very strong. Double braid is usually polyester and is also stretchy. Look at the Marlow booklet to see the various materials used and breaking strain.
Just looked at the Marlow Ropes website and it's rubbish - not a lot seems to work on it, like the Technical Page.......

 

[spinny]

[ QUOTE ]
I think they're all nylons.

But do any have any advantages?

[/ QUOTE ]

What I meant was use Nylon ropes with chaffing pieces where the nylon rope runs over edges.

Nylon and polyester are the two main materials used for mooring lines in small leisure vessels. Both have their pros and cons.
Nylon is more stretchy than polyester so is better when a vessel is surging backwards and forewards in a tidal harbour whilst tied up to the wall or rafted up to other boats.
Polyester is less stretchy but has better abrasive resistance. So this type of rope would be better used in an enclosed marina where the vessel is not affected by tidal movement or waves.
So for your particular situation I would recommend Nylon with chaffing pieces where the nylon runs over edges.

Don't even consider using polypropylene (Gets damaged and weaked by UV rays) and polyethylene ( Orange and weak. Only usually used as swim lines).

You may see larger commercial vessels using what you may think is polypropylene or polyethylene mooring lines but in bigger diameter - But don't get confused here they are mixes of the two called copoymers and polyolifins, and have been specially treated to prevent UV damage AMONGST OTHER THINGS. Also some of the bigger tanker mooring ropes can be made from dyneema which floats like polyprop and polyethylene. Infact dyneema (spectra) is made from polyethylene (HMPE high modulus poly ethylene) but its molecular structure has been changed to make it much stronger..
We use to use this dyneema 12 plait rope in 160mm diameter for pulling 'well heads' on the sea bed on the 'Grand Banks' off Newfoundland. Very expensive rope but light to handle.

 

[Refueler]

[ QUOTE ]
Don't use Polypropylene - it suffers badly from UV degradation and is also has considerably less breaking load than Nylon or Polyester. Nylon is usually recommended as it is 'stretchy'. Polythene is very hard, usually orange in colour, again not very strong. Double braid is usually polyester and is also stretchy. Look at the Marlow booklet to see the various materials used and breaking strain.
Just looked at the Marlow Ropes website and it's rubbish - not a lot seems to work on it, like the Technical Page.......

[/ QUOTE ]

Just to correct a bit ... Polyprop is a good mooring line as it is cheaper, can be had in various forms and not being so soft as nylon takes abrasion better. It also gives better indication when it's past it's sell-by-date by having powdery / flaky filaments apparent. Nylon doesn't.

It's actually the preferred mooring line material for ships all over the world.

But don't use DIY shop blue staple line - that is rubbish and I despair when I see odd boats use it. Fine for "grab-it, temp" lines but naff all use for serious work.

As to which is best ? Nylon will give elasticity but take care to make sure you have good size and not skimp. If you ever saw a nylon line break - you will know exactly why I say that. It can do serious damage with that release of stretch. It can kill.

Sorry to be dramatic - but even my small boat of 25ft in Yarmouthy IoW in a storm inside the breakwater broke a 12mm braid mooring line. Luckily no-one was on deck - we were in bed and it was like a cannon going off. Rail and deck were marked where it recoiled. Potoon had a gouge across it.

 

[pmyatt]

Which of the two has the best UV resistance, nylon or polyester. I have nearly always used nylon warps but they do become very stiff after a while - and washing them does not help. Am thinking of changing to polyester as it is not so prone to this hardening. Will make up for the loss of elasticity by using steel springs at the quayside end.

 

[spinny]

[ QUOTE ]
Which of the two has the best UV resistance, nylon or polyester. I have nearly always used nylon warps but they do become very stiff after a while - and washing them does not help. Am thinking of changing to polyester as it is not so prone to this hardening. Will make up for the loss of elasticity by using steel springs at the quayside end.

[/ QUOTE ]

Nylon has good UV resistance. Polyester has Excellent UV resistance as opposed to polypropylene which has poor UV resistance.
The hardening of the nylon which you talk about has nothing to do with UV it just happens to Nylon over time. For example I have seen coils of nylon go hard over a period of 2 to 3 years and they have not been exposed to any direct UV rays as they have been kept inside a warehouse all their life.
As time goes by they become harder which makes them more difficult to splice.
With Nylon it's a toss up as to what you order in the first place and to how soon it will be sold/used after it comes from the factory.
When talking about 3 strand nylon, stand factory orders/requests are for a 'medium lay', which is a good lay for retaining thimbles when splicing 'hard eyes'. But like I said earlier, if it is kept in stock for 2 to 3 years it hardens up to a tight lay and is a nightmare to manipulate and splice.
You can opt for loose lay from the factory which is OK for soft eye splices, but thimbles will drop straight out.

 

[S2Jimlad]

I prefer Polyester. It's nice to handle, work with. It has excellent UV resistance and superb load bearing capabilities. Not much in it though between it and nylon.

 

[Skyva_2]

I gave up on nylon as it becomes too hard to cleat, and use polyester with mooring compensators. After recent weather the lines are always doubled.

 

[nigelmercier]

Spam reported [now removed, so this becomes post #11. D'OH!]

 

[GrahamM376]

Don't use Polypropylene - it suffers badly from UV degradation and is also has considerably less breaking load than Nylon or Polyester. .....

On the contrary, do consider polypropylene. I use 2 x 24mm 4 strand polyprop mooring strops over the bow rollers and they have outlasted nylon by far. We are in a high UV area and no degradation problem after 3 years, used to replace nylon about every 18 months as it would burn where stretched over rollers.

Very large ships tie up with polyprop and, if it's good enough for them.............

 

[billcowan]

Chain every time.

UV not an issue, many times stronger than any warp, lasts for ever, doesn't chafe.

Make it stainless to avoid rust on your deck, make it long enough so it always makes a catenary.

Our 25' boat on a mooring all summer in what is virtually open North Sea, only a tiny reef between us and the full force of a Scottish noreasterly.
She has survived dozens of f8 gales.

One tip though, to avoid corrosion you need an insulated shackle where the SS joins the plain steel riser.

 

[cryan]

Nylon has gone out of favour on commercial vessels due to its rather wicked (read lethal) recoil when it parts. If you can afford it use Dyneema if not most vessels use polyprop.

 

[Daydream believer]

On the contrary, do consider . I use 2 x 24mm 4 strand polyprop mooring strops over the bow rollers and they have outlasted nylon by far. We are in a high UV area and no degradation problem after 3 years, used to replace nylon about every 18 months as it would burn where stretched over rollers.

.

i agree with this. Mooring lines can be divided into 3 - Permanent pontoon lines, mooring lines for temprary ie visiting a pontoon or lock etc & mooring to a buoy

Personally I prefer polypropylene as it floats, so in a lock etc when single handing my stern rope is poly to reduce risk of prop wrap
For visiting I use nylon as that is what came with the boat
For a buoy then poly plus a chain . The poly floats so is easy to pick up then i can lean over, grab the chain which hangs straight down & then take main load with that 7 the poly as back up
For main home berth I use poly as visitors tend to mess my lines up & it is cheap ( i bought 50 No 7 metre lifting strops for £ 0.50p each ) If no one else used my lines they would last several years but over winter the marina use my berth for storage of others & they usually knacker my lines if i do not get them removed first
1 Tonne SWL is ample for a mooring line on a pontoon berth

 

[Coaster]

Another vote for polyester. Our current mooring lines are now 6 years old, show little sign of wear and remain very easy to handle. Washing each year or two refreshes their appearance. However we are berthed in an enclosed dock basin.

 

[nigelmercier]

You guys do realise this thread is 5 years old, brought back to life by a spammer in #11.

 

[cryan]

You guys do realise this thread is 5 years old, brought back to life by a spammer in #11.

Lol. Obviously not . I should really stop looking at the forum when I wake up during the night!

 

[GrahamM376]

You guys do realise this thread is 5 years old, brought back to life by a spammer in #11.

#11 is your post bringing it back to life, I don't see any spam. Didn't notice the date of previous posts however.

 

[KellysEye]

We used multiplait nylon rope which is the only rope that doesn't have memory and thus can be coiled easily. I wouldn't touch polypropylene rope.