Shore Lines - Polyprop or Polyest?

Tim Good

Tim Good

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I want to buy 200m of shore line for cruising in adventurous places. I can't afford dyneema so the choice is between Polyester which is strong, easy to handle and UV resistant or Polyprop which is cheap, floats, not as strong and not UV resistant. I imagine trying to motor out 100m of waterlogged, sinking polyester could be a challenge?

Which would you got for?
 
Polyester or nylon. Avoid Polyprope except for a temporary stern line for use if other boats are about. Easier to take the rope out coiled up in the dinghy and pay it out rather than towing it out from the yacht. Also worth considering having an Ankrolina.
 
northcave said:
I want to buy 200m of shore line for cruising in adventurous places. I can't afford dyneema so the choice is between Polyester which is strong, easy to handle and UV resistant or Polyprop which is cheap, floats, not as strong and not UV resistant. I imagine trying to motor out 100m of waterlogged, sinking polyester could be a challenge?

Which would you got for?
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Dyneema's the last thing you'd want, anyway. Shock-absorbing properties close to zero.
We have a choice of polyprop and polyester: as said, polyprop's best quality is that it floats: easy to get ashore and less likely to get under the boat if making a quick getaway.
 
BobnLesley said:
Another vote for climbing ropes; if you enquire amongst the climbing fraternity, acceptable second-hand ones can generally be sourced, as once they've suffered a few long fall-arrests, the climbers stop using them; or the sensible ones do anyway.
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Interestingly the reason we are going to adventurous places is to climb and climbing ropes are not ideal. Firstly climbing ropes are designed in a very different way and you'll never get a breaking load listed on any climbing rope specification. It is rated against the number of fall factor 2 falls. I.e. Someone / thing falling 2m on a 1m piece of rope. If this happens, although very rarely, it can and does do significantly damage to the rope. After X many falls like this it has to be retired.

Buying old rope from climbing centers is cheap I agree but you have no idea what they were used for and how many falls they have had. I would not climb on a retired climbing center rope and I certainly wouldn't put my price and joy on one if the weather kicked up.

Lastly some people have gone out and tested the direct breaking load of a new climbing rope. It fails at around 18-20kn or 1.8-2 T in static loading. If you calculate the forces generated by a reasonably heavy boat in a blow, they can well this. Bottom line, We'll have over 200m of climbing rope on board but I'm only using for climbing.

cmedsailor said:
200m rope is a lot and heavy. So, I agree, consider also ankarolina on a reel though I am not sure you can have 200 meters on one reel. 200 meters?? Are you sure, it sounds too much!!!
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200 in total flaked into two bags, not 200m in one go. I agree that is a lot and would not fit on a reel.

macd said:
Dyneema's the last thing you'd want, anyway. Shock-absorbing properties close to zero.
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There are many expedition boats that use Spectra Dyneema where the ultimate strength of a shore line which is pre tensioned is more important than the stretch. If I could afford it then I would. Par example:

JHH5_106650.jpg


PA050004.jpg
 
We don't use shore lines very often each year so I got 200m of 12mm polyprop for £35 online which I've used for the last 5 years without any problems. We flake (stuff) it into a bag and I swim ashore with it being handed out from the bag. All works very easily and being floaty can't get caught round the prop easily if reverse is needed.
 
I use seasteel, which is good quality polyprop. It floats is its key advantage: try towing from a dinghy (or even pulling in by hand) 200m of sinking line over rocks and kelp, it's virtually impossible.

If worried about weight, note that the forces on shorelines are quite modest, much less than those on anchors since:
- usually there are several lines
- by definition the pull will be from landwards so probably the boat will be quite sheltered (at least from that direction)
- boats attached with shore lines don't surge around much so snatching forces are low.

Somewhere around 12 or 14mm is entirely adequate for a 40 - 45' boat I think. Interesting and authoritative article (from another of this parish) here: http://www.bethandevans.com/pdf/High latitude equip.pdf
 
We had two flake bags of polyester but I encountered the problems others have described: trying to drag it along the bottom where it would snag on any number of obstacles. Taking the coil or bag ashore in the dinghy is all very well in theory but in reality the main coil of it needs to be on the boat where the crew can get it on a winch to haul in. I switched this year to 100 metres of polypropylene, which after limited experience seems to work very well.
 
Skip Novak uses polypropylene too (prominently placed on large reels either side of the mast). And the sailing he does definitely qualifies as "adventurous places".

Big-seas.jpg
 
The stuff shown on the reels on Pelaigic Australis is probably seasteel: http://www.gaelforcemarine.co.uk/en/Gael-Force-Seasteel-Rope/m-764.aspx

It's proper high quality rope and about as different from the horrible bright blue polyprop as it's possible to find. One of the key differences is that the blue stuff is made from fibres split from a raffia like tape whereas proper polyprop ropes are made from multiple strands of single spun fibres.

PS: weather to be in a sheltered anchorage:
jpgk_SpzX9L46.jpg

with a line (nylon in this case) to a tree!
jpgipRCOxB69q.jpg
 
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Interesting thanks.

The Seasteel has a breaking load of 3,610kg on 14mm compared to 3,050kg on the Timko multifilament alternative.

I wonder if the Seasteel is as easy to work or if it becomes stiff and horrible? Seems very good value at £87.49 for 220m!!!!
 
Boom!!!!

Just spoke to to them on the phone. The Seasteel is good but the SeaGold Plus is even stronger again!!!! 30% stronger than Seasteel which is putting 14mm at over 4T.

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Cheers for the referral JDC!
 
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