Anchor rope.

mick

Well-Known Member
Joined
10 Aug 2001
Messages
933
Location
Clyde
Visit site
I have a Sadler 26 with 40m of 8mm chain, and I want to add 30m of either 16mm nylon or the same of polyester rope. This may seem excessive to some, but we sail on the west coast of Scotland and want as big a security margin as possible. Those of you who sail in the same area will appreciate this. Nylon is strong and elastic; polyester is not quite as strong or elastic, but stays soft. This latter consideration is important to me. I have had to remove the nylon anchor line already on the boat as it is badly chafed around the thimble, but it is so stiff I can't resplice it. Because of this I really would like to use polyester and would be grateful for any comments.
 
1. polyester floats - however as you have 40m of chain out first this isn't going to be an issue for you!
2. 14mm is normally considered a match for 8mm chain
3. anchorplait (octoplait) is nylon but handles better than 3 strand - however it wears faster than 3 strand too.

Concerned over your need to have soft rope to handle - you have 75 kg of chain and anchor (I assume) which suggests that you aren't planning to do it all by hand.

Not sure that I have told you anything you didn't know.
 
You're only 26ft use 14mm. 2 things will happen if you use 16mm - 1, you will lose lots of space and 2, you will 'lose' more $$ than you need to. 14mm spliced to 8mm chain is a very good match.

Use polyester. I know people will read this and say use nylon for the extra stretch. If you are planning on using your rope WELL OVER the manufacturers recommendations than you MAY notice the diffreance between the 2. At Working loads you will not notice any differance. This applys to smaller boats only i.e 32-35ft max, after that use Nylon.

When you wet nylon it loses 10% of its strength and so it has the same loads as polyester.

DO NOT use polyester if you are fitting/have a Auto rope to chain winch though, they just don't like it, use nylon.

By the way 'Duncan' - pure polyester does not float and where did that bit about 8 braids wear faster than 3 strands come from?. Never seen anything to suggest that is correct. If you are talking about how 8 braids sometimes 'fur' up a bit (as some 3 strands do as well) that is fine and actually good for the rope, keeps it cooler. 'Fur' means a bit furry on the outside not great daggs hanging off or anything like that.

Splicing you have choices - If you are using a Auto Rope to chain winch splice direct to the chain. 2 choices with this, 1 being Hylas's above and the other being the 'back splice' way. I prefer the back splice but done right either is fine.
If you are not using one of those winches go the thimble and shackle way. This means you have a nice long length of rope to use for other tasks if required i.e towing, med mooring and etc.
 
[ QUOTE ]
Mick wrote:
Nylon is strong and elastic; polyester is not quite as strong or elastic, but stays soft. This latter consideration is important to me. I have had to remove the nylon anchor line already on the boat as it is badly chafed around the thimble, but it is so stiff I can't resplice it. Because of this I really would like to use polyester and would be grateful for any comments.

[/ QUOTE ]Mick you are absolutely on the right track. For anchor rode, polyester is generally superior to nylon, as the latter stretches which encourages “sailing” when at anchor. Three-strand nylon tends to harden in the marine environment and becomes difficult to handle, and tends to twist, and knot, under load. Square, 8, or 10 plait rope makes ideal anchor rode, as it is easy to handle, and stows in less space.

To expand on the above comment re "sailing", the stretching nature of nylon is not necessarily a good thing. If you are using long lengths, you just end up with a big bungee, which will do more harm than good particularly in gusty conditions.

Use nylon for short lengths (e.g. as a snubber on all-chain) and polyester for long lengths.

[ QUOTE ]
Duncan wrote:
1. polyester floats - however as you have 40m of chain out first this isn't going to be an issue for you!
2. 14mm is normally considered a match for 8mm chain
3. anchorplait (octoplait) is nylon but handles better than 3 strand - however it wears faster than 3 strand too.

Concerned over your need to have soft rope to handle - you have 75 kg of chain and anchor (I assume) which suggests that you aren't planning to do it all by hand.

[/ QUOTE ]Duncan, polyester does not float.

"Anchorplait" is also not just nylon, it is available as both. I am unsure which Philip is referring to but in the context of his reply to Mick's post I assume he means polyester. I also am aware of no reason 8 braid should wear faster than 3 strand.

Lastly, the rope may be manually laid as it is brought in, and also is handled at times other than when retrieving the anchor.

/forums/images/graemlins/crazy.gif

More with regard to 3-strand vs 8-braid. The latter has slightly more stretch at breaking load, but actually better shock-absorption. Here is a quote from GMac, the resident chain and rope expert, who may show up on this thread - no, already beat me to it /forums/images/graemlins/cool.gif

<span style="color:brown">It's just that the 8 braid has more 'smaller' strands, in this case 8 of them and the 3 in 3 strand. It's is easier for 8 smaller to 'work' than the 3 bigger ones i.e less load per bit so works earlier and longer. Say 1000kg / 8 = 125kg per strand in the 8B against 333kg per strand in a 3 strand. Hence the earlier the rope starts reacting to the loads the less load is required to start absorbing shock.
</span>
Hope that's helpful.
 
I am also very impressed by octoplait. I got mine at a very good rate from Mr B Edwards (bje@barryedwards.co.uk). He has a small rope selling outfit and does excellent prices. Contact him and he can let you know what he has got.

NB I have no personal connections with him, I'm just a satisfied customer
 
GMac, and others, my apologies for the confusion re polyester floating - for a brief moment some element of brain fade caused me to confuse polypropelene with polyester; it won't happen again!

re Anchorplait being nylon - I was advised when purchasing mine by the supplier (English Braids). Clearly my presumption that they were refering generally to 'anchorplairs/octoplaits' being nylon rather than just theirs was false (and as all presumptions, dangerous).

Finally my comments on wear relate cut and abrasion resistance over time. Esentially the hardening up of 3 stand nylon, often mentioned as a disadvantage in this thread, also seems to improve it's resistance to cuts and abrasions whilst anchorplait stays softer. With further thought I suspect that the same hardening may well accompany a weakening of the rope so it wasn't particulily constructive either!

/forums/images/graemlins/frown.gif
 
Mick

We also sail W Coast Scotland and have 35m chain spliced to approx 40m octoplait. Never had a problem. Octoplait is easy to splice yourself and is much kinder on the hands than any of the others.

Hope this helps
 
When you use rope the boat sails about and when blowing lays almost side on by the time the line takes up and the bows finaly come into wind before shearing off the otherside!

After years of chain, im always nervose with just line when it blows, untill i feel the check of the line and anchor, i wonder if the lines been cut or chafed through!!

I also wonder if i have enough chain on the anchor (just 5m of 10mm) Life with lines very stressfull, but where could i put even 40m of chain??

Just remember that with line you will sail about a lot!! Perhaps even about your own anchor, its happend to me and ive brought the anchor in fluks first!!
 
One other point to add: if you have a windlass with a rope/chain gypsy the rope needs to be 3-strand and of a fairly 'hard' construction or the gypsy won't grip it. Also each gypsy works with only one size of rope, for example a Lofrans gypsy for 8mm chain requires 12mm rope.
 
[ QUOTE ]
One other point to add: if you have a windlass with a rope/chain gypsy the rope needs to be 3-strand and of a fairly 'hard' construction or the gypsy won't grip it. Also each gypsy works with only one size of rope, for example a Lofrans gypsy for 8mm chain requires 12mm rope.

[/ QUOTE ]

Small correction - Lofrans prefer 14mm rope on 8mm chain. 12mm on 6 or 7mm chians.
 
Top