3 strand Nylon service life

[slowgoesit]

Background, currently looking for a trawler. Not new to trawlers, but haven't had one for some time.
I have a 600' spool of 3 strand, 3/4" nylon rope from Tubbs Cordage. It was manufactured in 2003. I obtained it in 2004. It is on the original spool/reel. It has been stored indoors in climate controlled, dry storage, not exposed to sunlight since 2004.
I have been searching for something definitive that states age limits for nylon cordage, but haven't found much to date.

My intent is when we find a boat, to use for dock lines etc. I don't feel comfortable using for anchor rode, because a single failure would leave me without an anchor, where as used as mooring lines, etc, there would be redundancy (other lines, springs, etc).
Anyone out there have advice as to the suitability of 16 year old (new old part) 3 strand 3/4" nylon rope?

 

[psneeld]

you could always failure check a small portion of it.

 

[O C Diver]

I have dock lines on my charter boat that were older than that. I would be surprised if cordage has much deterioration from sitting.

Regarding the age of my dock lines, life expectancy is mostly a function of how benign or malignant an environment you dock your boat in and making sure your lines are long enough to stretch as opposed to shock load. A marina with substantial wave action, boat wakes, or tidal currents can wear out lines in less than a season, especially if they shock load.

Ted

 

[slowgoesit]

you could always failure check a small portion of it.

I appreciate the input, but I have no way of testing to failure a rope that is advertised as having a 12,000 lb plus breaking strength!
I tend to think that they would be fine as dock lines, or to raft up someone, or tow someone, etc, but at the end of the day, it's just my best guess, I was hoping something definitive to assist me in my risk analysis.


Ted: Appreciate the input. I also am about half way through your odyssey of taking apart and putting back together your boat! Really interesting thread, and beautiful work. Sean is a keeper! However, I think I will have to rely more on my own resources to fit out/maintain a boat. By checkbook doesn't have that many zeros in the balance!

 

[Mr. Ed]

The factors that most affect line are UV exposure, ozone, chemicals and wear. Unless the spool was stored badly for the first year, you should have essentially a new spool of line. If it was just exposed to the atmosphere/sunlight for the first year, you could strip off the outer wraps of line and the rest should be just fine.

 

[koliver]

More important than its chronological age is its original quality. I have some very old (at least 25 yrs, but likely 10 or 15 yrs older) 3/4" Samson Yacht braid that I use for tyup lines in my shelter. I also have some 4 or 5 yr old 3/4" generic brand tyup lines that I carry on board. Huge difference in quality. The Samson I would trust as a hurricane tie (not that there will ever be a need for this level of safety) but the generic stuff is already failing.

If you don't know its quality, peel off 20' or so and test it.

 

[dhays]

Background, currently looking for a trawler. Not new to trawlers, but haven't had one for some time.
I have a 600' spool of 3 strand, 3/4" nylon rope from Tubbs Cordage. It was manufactured in 2003. I obtained it in 2004. It is on the original spool/reel. It has been stored indoors in climate controlled, dry storage, not exposed to sunlight since 2004.
I have been searching for something definitive that states age limits for nylon cordage, but haven't found much to date.

My intent is when we find a boat, to use for dock lines etc. I don't feel comfortable using for anchor rode, because a single failure would leave me without an anchor, where as used as mooring lines, etc, there would be redundancy (other lines, springs, etc).
Anyone out there have advice as to the suitability of 16 year old (new old part) 3 strand 3/4" nylon rope?

Great question. From my understanding, the nylon will degrade through exposure to UV (worse in the presence of O2), exposure to chemicals, heat, and exposure to water containing salts. It also changes structure when exposed to cyclical loads. So the very definition of a dock line. Nylon just happens to do better than many other materials in this environment.

You can find a lot of information in the climbing community (recreational and vocational). Those guys take safety seriously and their discussions about rope make our discussions on anchors look tame in comparison.

Climbing rope manufacturers place an arbitrary shelf life on their climbing rope of anywhere from 5-15 years. No one wants to take the liability of disputing those, and most of the articles that have been written that DO dispute those have been removed. Again, liability is a big issue in the rock climbing industry.

Here is an actual test done on 20 year old rope by Black Diamond. http://www.blackdiamondequipment.com/en_US/experience-story?cid=qc-lab-old-vs-new-gear-testing

So that spool of 3 strand should be fine to use if it has been stored as you say. I think it would be fine to use for an anchor line as well. Even so, we all have to make our own decisions. If you are uncomfortable using it, then don’t. If you decide to dispose of it, I’ll help you out. I’ll send you the money to ship it to me and I’ll dispose of it for you.

 

[psneeld]

I appreciate the input, but I have no way of testing to failure a rope that is advertised as having a 12,000 lb plus breaking strength!
I tend to think that they would be fine as dock lines, or to raft up someone, or tow someone, etc, but at the end of the day, it's just my best guess, I was hoping something definitive to assist me in my risk analysis.


Ted: Appreciate the input. I also am about half way through your odyssey of taking apart and putting back together your boat! Really interesting thread, and beautiful work. Sean is a keeper! However, I think I will have to rely more on my own resources to fit out/maintain a boat. By checkbook doesn't have that many zeros in the balance!

Being creative is the trick to being economical in the boating world.


What forces are involved every day that the lines have to meet and exceed? There's a start.

 

[Comodave]

If it is still supple and not stiffened, I would use it. My general guide is when it starts getting stiff I get rid of it.

 

[slowgoesit]

Mr. Ed, the spool still has the paper wrapping that came with it, so UV shouldn't be an issue in the first year. Since then, it's been stored out of the sun, climate controlled, no ozone, or chemicals.

Koliver, not sure how I could possibly test it.

Dave, I really appreciate the offer of disposing of it for me, but I wouldn't to impose on you, really I wouldn't! I used to have my 34' Monk in Gig Harbor, tied up to Stanich's dock, two docks over from the USCG station dock. Do you anchor out?

Comodave, the rope is supple, actually "limp" is a better description, just like brand new rope.

Soooo . . . I have put the rope before the boat, now just need to get the boat!

 

[Pete Meisinger]

Honestly, I suspect it is as good as new. But if you want to test it why not take a piece and tie it to the frame or engine mount on your car and use an engine hoist to exert some lift. It should easily lift the front of a car. Go buy 5 feet of similar new line and try it again, see what the new one will lift.

Not very scientific but if it will lift a car it should hold your boat in place along with 4 or 5 other dock lines.

pete

 

[slowgoesit]

Honestly, I suspect it is as good as new. But if you want to test it why not take a piece and tie it to the frame or engine mount on your car and use an engine hoist to exert some lift. It should easily lift the front of a car. Go buy 5 feet of similar new line and try it again, see what the new one will lift.
Not very scientific but if it will lift a car it should hold your boat in place along with 4 or 5 other dock lines.
pete

Pete, good thoughts, but my heaviest vehicle weighs only 7000 lbs, so even lifting the front of the F-350 would probably only apply about 4,000 lbs tension to the rope, which is rated at over 12,000 lbs. Of course, if it broke at 4,000 lbs, I'd KNOW that it is bad, wouldn't I?!?

 

[sdowney717]

It seems to me, the rope will be fine, I have some old ropes as dock lines, 3/4" nylon, and they are fine.

 

[Sailor of Fortune]

I would think that as" new rope"...Why would you think it would deteriorate? It seems to me that you have stored it under ideal conditions. Consult manufacturer if in doubt but I bet they will say its "New"

 

[dhays]

Dave, I really appreciate the offer of disposing of it for me, but I wouldn't to impose on you, really I wouldn't! I used to have my 34' Monk in Gig Harbor, tied up to Stanich's dock, two docks over from the USCG station dock. Do you anchor out?

We keep the boat at Murphy’s Landing. It is the condo marina that is at the head of the harbor SW of the Donkey Creek outflow.

So, we leave Gig Harbor, weaving through all the boats anchored in the harbor to go to other Puget Sound locations to anchor out.

 

[rsn48]

I echo what some one else said above, call your local REI and talk to the climbing guys/gals there for an opinion on a usable life span for your line.

 

[BruceK]

If it doesn`t come with a "Use By" date, has done no work, and been stored in ideal conditions, hard to imagine it is age compromised.

 

[High Wire]

Use it and monitor periodically just like anything else. Nothing about a boat is set and forget.

 

[FF]

"If it is still supple and not stiffened, I would use it. My general guide is when it starts getting stiff I get rid of it."

I just downgrade it when it becomes stiff.

From anchor line to dock lines .As there are more than just one.

From dock lines to long stuff holding in the station wagon.

 

[sbu22]

I keep my storm lines in covered but not air-conditioned storage. Nylon 3/4" 3 strand. They are in good shape and with reasonably good hand. Probably been used 1/2 a dozen times in 10 years. They have not been subjected to a lot of stress from a big blow - probably 60-70 k gusts on a couple of occassions.

This is on a 43 - they're pretty stout for the application.

Regarding "stiffness" - what causes that? Some say accumulated dirt and crud. Others state it's deterioration of the fibers. I do know that getting stiff nylon wet will temporarily cure the stiffness problem.

 

[Sailor of Fortune]

I keep my storm lines in covered but not air-conditioned storage. Nylon 3/4" 3 strand. They are in good shape and with reasonably good hand. Probably been used 1/2 a dozen times in 10 years. They have not been subjected to a lot of stress from a big blow - probably 60-70 k gusts on a couple of occassions.

This is on a 43 - they're pretty stout for the application.

Regarding "stiffness" - what causes that? Some say accumulated dirt and crud. Others state it's deterioration of the fibers. I do know that getting stiff nylon wet will temporarily cure the stiffness problem.

soak them in a bucket with water and fabric softener. Rinse well and dry

 

[Donna]

Are we really talking about rope without a boat? It’s really easy to tell if rope needs to be replaced, used or not used.