Anchor rope - Nylon vs Polyester

[Tonny9]

What fact have I overlooked?
If you read various books and articles, most people prefer nylon anchor ropes instead of polyester.
I consider polyester to be the best anchor rope, except for the stretch.
So, if you could get a polyester rope with stretch like nylon, or almost like nylon, then this would be the best anchor rope.
So far, I think everyone agrees.

In the last book I've read, Rigging modern anchors, by Drew Frye, he writes that he almost experiences polyester rope as a chain, just without the catenary effect.

If I look at Liros anchor rope in polyester, then it extends 15% at max workload.
Their corresponding nylon rope extends 20% at maximum workload.

It's not that big a difference and a stretch of 15% should be plentiful in most cases and certainly don't make the rope feel like a chain without catenary effect.

I am convinced that Drew Frye has experienced what he writes, and I am convinced that the Liros writes is correct.

So, I must ask the question, what facts are I not knowledge of?

Is all polyester rope perhaps pre stretched in the United States? And therefore, with significantly less stretch. Has Liros done something special?

Apparently, there are far more Europeans than Americans who prefer polyester as anchor ropes.
Maybe there's a good reason for that?

Does anyone have an idea why there seems to be this different view?

[slug]

The physical properties of nylon rope are degraded when you get it wet

Nylon also has chafe issues

I prefer polyester double braid

[HankOnthewater]

As you do Tonny, I also often scratch my head with conflicting data, and 'evidence'. Yes, there are different manufacturers, making all ropes with different properties.
And then, there are different ways to measure things, like stretch; it that that at breaking strength? at working load? And what is working load? Breaking load divided by 3, 4, 8 or 10?
As you wrote/copied I have not seen any polyester rope with a stretch of 15%, which ever way it is measured.

Yes, I believe that nylon loses some of it strength when wet, not sure by how much hmmm, I see in a post above by 70%... that seems a lot to me, I thought it would be around 10-15% not more, maybe even less?
Yes, 3 strand nylon becomes very hard and difficult to stow, hence 8 or 12 plait would be better.
Yes, nylon is slightly more prone to chafe, due to a lower melting point. For type '6' nylon it is around 220 degrees C, and for type '66' nylon around 260 degrees.... Good luck finding out what type of rope it is made out of, never seen that designation on a coil. BTW melting point for polyester rope is around 240 degrees, but can vary depending on manufacturer and process.

But. wait ... there is an alternative: double braid construction, core is nylon, and braided cover is polyester. Not saying it is the best anchor line, but I use it for my docklines.

[Tonny9]

Here's a copy from Jimmy Green Marine, UK

• Information

LIROS 14mm 3 strand Polyester is suitable for boats up to 12 metres length overall or 5 tonne displacement (LIROS guide).

LIROS 3 strand polyester is the traditional mooring rope choice:
Manufactured from 100% polyester to DIN EN ISO 1141 standard (previously DIN EN 697, DIN 83331)
High strength and abrasion resistance.
Retains flexibility throughout workinglife.
>15% working stretch provides good shock absorption.
LIROS Break Load= 3600kg
Available in:
White - LIROS article 00111
Black and Navy - LIROS article 01110



And here the same rope as pre-stretched.
I can't tell the difference between the two pieces of rope.

Perhaps the fact that it is available in two stretch variations that cannot be seen difference between helping to cause some confusion – I could have a suspicion of it.


copy:


Prestretch 3 strands
Fabricant : Liros

Model R012104
Pre-stretched for low elongation. Use for wire halyard leaders, control lines on dinghies and small boats - heat set. Perfect for many industrial applications.

Use: Halyard and control lines

Cover: Polyester, 3-strand, heat set

Core:

Splice: Ideal for cable / rope halyard

Breaking load:
- 4 mm 420 kg

Stretch characteristics: 4%

[Vasco]

I feel you're overthinking this. Go with chain. If you have to have line, nylon will do.

[Training Wheels]

We use sta-set polyester. Don’t care about the stretch, as we always use a stretchy bridle. Double braid let’s us use smaller diameter, lighter line with the same or greater strength of nylon. Works for us.

[Don C L]

I got a smaller boat and I've always had nylon and chain combo, and I always assumed nylon was best due to ability to stretch, and thus its shock absorbing abilities. But now that advantage over polyester seems less important. Not long back I had a good deal of nylon out and it was blowing pretty well, and the line stretched so much I briefly panicked thinking I was dragging. When I replace it all, I will definitely be considering a little more chain and polyester.

[slug]

Originally Posted by Don C L

I got a smaller boat and I've always had nylon and chain combo, and I always assumed nylon was best due to ability to stretch, and thus its shock absorbing abilities. But now that advantage over polyester seems less important. Not long back I had a good deal of nylon out and it was blowing pretty well, and the line stretched so much I briefly panicked thinking I was dragging. When I replace it all, I will definitely be considering a little more chain and polyester.

Everything is a compromise , everyone has an opinion

Nylon...polyester

Ford ...Chevy

Just look at the crazy anchor thread !

[CarlF]

Good piece by Steve Dashew favoring polyester over nylon

https://www.petersmith.net.nz/boat-a...right-rode.pdf

[Lepke]

Poly doesn't hold up well in UV light. Old poly gives you splinters.

[donradcliffe]

Poly AND Nylon don't hold up well in coral.

[Jim Cate]

Originally Posted by Lepke

Poly doesn't hold up well in UV light. Old poly gives you splinters.

I think you are referring to polypropylene, not polyester (dacron). Polyester has relatively good UV resistance and I've never ever had it splinter... like polypro does.

And FWIW, I think correctly sized dacron will surely stretch adequately when used as rode. We're talking about many meters typically, not a short snubber. The chap reporting that dacron felt like chain is delusional IMO.

Jim

[rslifkin]

I've been thinking of going with polyester for my new anchor rode, but I'm stumbling across a few roadblocks that may push me back to nylon. I can get 3 strand polyester, but I'm not sure if 300 feet of 3 strand will lay nicely enough in my locker (although the old 150 feet of 3 strand nylon did fine). And then 75 feet of chain has to go in after.

Here in the US, I've had no luck finding 8 plait polyester. I can get double braid, but as far as I know, it can't be spliced to chain in a way that will feed through my windlass.

Planned line size would be 5/8" (and that's what the windlass is meant to accept), but I've got a test piece of 3/4" nylon 8 plait on the way to see if the windlass will handle it. Maxwell says it won't work, but looking at how 5/8" sits and knowing how squishy 8 plait is, I have a feeling it might. I'm figuring that going with bigger nylon might mitigate some of its downsides compared to polyester.

[slug]

Originally Posted by rslifkin

I've been thinking of going with polyester for my new anchor rode, but I'm stumbling across a few roadblocks that may push me back to nylon. I can get 3 strand polyester, but I'm not sure if 300 feet of 3 strand will lay nicely enough in my locker (although the old 150 feet of 3 strand nylon did fine). And then 75 feet of chain has to go in after.

Here in the US, I've had no luck finding 8 plait polyester. I can get double braid, but as far as I know, it can't be spliced to chain in a way that will feed through my windlass.

Planned line size would be 5/8" (and that's what the windlass is meant to accept), but I've got a test piece of 3/4" nylon 8 plait on the way to see if the windlass will handle it. Maxwell says it won't work, but looking at how 5/8" sits and knowing how squishy 8 plait is, I have a feeling it might. I'm figuring that going with bigger nylon might mitigate some of its downsides compared to polyester.

Don’t know your boat...in general it’s best to go all chain

Rope is for second anchors , special situations, small boats ...

Rope chain rodes are alway a compromise .

Your boat is big enough to carry a decent length chain rode

[rslifkin]

Originally Posted by slug

Don’t know your boat...in general it’s best to go all chain

Rope is for second anchors , special situations, small boats ...

Rope chain rodes are alway a compromise .

Your boat is big enough to carry a decent length chain rode

I've thought about it, but I'm not cruising in areas with coral or lots of rocks on the bottom, etc. So I can't see needing more than 75 feet or so of chain for abrasion resistance.

As far as the boat, it's a planing hull powerboat. Putting 350 feet of chain in the bow vs 75 feet + 300 feet of line is an extra 250 lbs. On this boat, that much extra weight up forward is noticeable in terms of performance when running on plane. As in every 150-ish lbs added up forward costs about 0.1 kts at a given engine power setting. So I'd rather not carry around more chain than I need. Of course, if I were cruising in areas with coral, etc. I'd carry more chain because it would be necessary.