Mooring pendant chafe guard

[chris95040]

Hi folks,

I could use some advice on my mooring pendants. I'll start by describing my current setup.

I'm in a spot with 5 miles of fetch in the direction where we occasionally get some pretty significant storm winds.

The boat is about 20,000 pounds, 40 feet long.

The mooring is a 1000 pound mushroom.

The mooring pendants are identical 7/8" double-braid with spiced eyes, only about 15' long.

i bring one line through the port chock and to the port bow cleat, the other to starboard. There's a little interference with the bow rail that i'm sure the chafe guard can handle, and i need to move my furler line but other than that it seems like a simple, strong setup. See first attached photo.



Today after some good wind and waves i went and took a look at everything - I pulled back the chafe guard a bit to see where the lines each pass over the chocks and they were clearly squished - sort of a dent or dimple just where they sit in the chock - my second photo attempts to show this but it doesn't really jump out at you in the picture.



The line wasn't stiff like anything had melted and it seemed to disappear if i worked the line a little, but I was wondering if this was just the kind of squeezing that cranks up the friction and causes lines to fail.

It makes me think maybe my chafe guard is insufficient.

I need to extend the chafe guard anyways to protect from occasional contact with the bow anchor, is it safe to just add a second layer of chafe guard or does that make things worse? I've read that trapping heat is a potential factor although my intuition tells me the more chafe guard the better and if the line is really generating any significant heat you are probably hosed regardless..

Maybe I should get slightly longer pendants to have less of an angle as they pass through the chock and head down to the mooring ball.

Thanks for any advice!

[dfelsent]

A few thoughts.
Will you get a fairer lead by crossing the pendants? Not sure that’s a good idea but may be worth a try.
Our local mooring company has been using dyneema sections from the clear through the chock coupled to a nylon lower section.
They have had good results, ie a lack of failures.

http://www.willardandsons.com/cyclone.html

Has an explanation.

[Manateeman]

You can coat a pendant with a polymer that is used by tug boats. Any major line company might also do it as they use it in the oil field and ships. Don’t mix a lot up...comes in different stiffness finished. I don’t use it on my snubbers.
No chafe gear needed.
Manatee

[chris95040]

Thanks for the suggestions, great stuff.

Since my problem seems to be where the line passes through the chock and heads down to the ball I think a longer pendant to decease the down angle when exiting the chock will help.

I’m really intrigued by the idea of having a length of dyneema for the boat side. Makes a lot of sense that a non stretchy material sitting in the chock will be less chafe prone.

1. Anyone care to comment on if it’s foolish to ‘double up’ on anti chafe gear on a nylon line?

2. Anyone using those lengths of dyneema on the bow? What do you use for chafe guard on it, if anything?

[Matt Johnson]

We often use 3' Dyneema pendants with our dock lines if bad weather is expected. Our lines lead over the toerail (a 1/2" round topped toerail) with no proper chock - tons of chafe potential with this poorly designed set-up. We'd use the pendants all the time, but it prevents adjusting the lines on deck, so they only come out when needed.

If we don't have the dyneema pendants rigged, you can hear sawing all night as the line stretches back and forth over the toerail. With the dyneema, there is zero noise. That alone tells me it's working better than just our typical chafe guards.

Matt

[chris95040]

Originally Posted by funjohnson

If we don't have the dyneema pendants rigged, you can hear sawing all night as the line stretches back and forth over the toerail. With the dyneema, there is zero noise. That alone tells me it's working better than just our typical chafe guards.

Neat, that’s a great observation. (And with the things that run through my mind listening to noises like that, it’s worth it for peace of mind alone.) Do you use any additional chafe guard on the dyneema where it hops over the toe rail?

Anyone use dyneema long-term, on a mooring? It seems like a newish strategy so I’m nervous about any unexpected failure mode (UV exposure?) that isn’t encountered when only using it for storms.

[jtsailjt]

Originally Posted by funjohnson

We often use 3' Dyneema pendants with our dock lines if bad weather is expected. Our lines lead over the toerail (a 1/2" round topped toerail) with no proper chock - tons of chafe potential with this poorly designed set-up. We'd use the pendants all the time, but it prevents adjusting the lines on deck, so they only come out when needed.

If we don't have the dyneema pendants rigged, you can hear sawing all night as the line stretches back and forth over the toerail. With the dyneema, there is zero noise. That alone tells me it's working better than just our typical chafe guards.

Matt

That sounds like a great idea to me! How do you attach your nylon dock lines to your dyneema pendants? I'm thinking that maybe making about a 2' soft shackle out of dyneema and put that around the cleat, then out through the chock and through the loop (bowline or braided) in the dock line? How do you do it?

[Manateeman]

Greetings all. Our mooring pendant is covered dyneema spliced up by Captain Frank Lasky Westfield MA. 877-568-4182.
We then applied a two part coating from Industrial Polymers. 800 766-3832 in Houston Texas.
One gallon is enough for 5 pendants. This stuff is used on tugs and ships.
Look at the Trukote stuff. I think we used CS 100. Very stiff coating.
Very stiff so use something round and plastic to hold your eye open.
Try a very small batch on some disposable line first.
We have two snubber lines. The pendant hangs loose. They attach at a mooring ball or a low drag float when anchoring. I connect to a huge stainless swivel used in scalloping from New Bedford.
You can coat as much or as little of the lines as you wish. These coating are used on tugs and ships and helicopters. I have my eye splices done at Consolidated Rigging and Marine in Jacksonville FL. 800-521-9473.
Happy trails to you.
Mark a heavy duty manatee

[Matt Johnson]

Originally Posted by chris95040

Neat, that’s a great observation. (And with the things that run through my mind listening to noises like that, it’s worth it for peace of mind alone.) Do you use any additional chafe guard on the dyneema where it hops over the toe rail?

Anyone use dyneema long-term, on a mooring? It seems like a newish strategy so I’m nervous about any unexpected failure mode (UV exposure?) that isn’t encountered when only using it for storms.

We use some dyneema braided rope jacket as a chafe guard since I had it on hand when slicing the pendants. But if using it with decent chocks, I don't think it's necessary - check it periodically to make sure it's not chafing.

Each end of the pendant has a loop large enough to go over the cleat (so I can end-for-end the lines later in life if needed). One loop goes on the cleat, the other gets the dockline tied to it. I usually just use a bowline since this isn't permanent and I worry about untying the lines later. Mooring lines would be different.

Matt

[bollard]

I had trouble at my chocks. 1. I added Dyneema extensions (5' long each) and criss-crossed the lines to get a better lead. Worked like a charm, no chafe, no squish, well worth its price in safety (approx. $250 for a pair at Defender or Westmarine).

[hlev00]

If the Dyneema extension is smaller than the nylon part, I would be concerned about the Dyneema cutting through the nylon in rough conditions. I've thought about using a similar arrangement for a snubber / bridle on a monohull.


The Willard offering looks nice. They talk about the ability to use smaller diameter, but how small is safe?


Is this a legit concern?

[Manateeman]

Hi. I forgot some info in my post. By pendant, I mean the main connection line between the mooring buoy. Bu snubber, I mean the single or bridal that absorbs shock. I have a pendant which is covered by a material designed to protect the dyneema. I think it’s braid on braid. We had it spliced up then coated it with the polymer the ships and tugs use. The coating becomes the chafe guard. The pendant cannot absorb much shock so at the mooring ball I have two additional lines. Nylon, with poly Velcro on chafe guards. One can use elk hide...there are various solutions. I have a bridal with rubber bungee things and a chain claw.
Two types of chain claws, a Prusik loop..your choice. But the idea is to have shock absorption. There are sailors who have published guidelines on how long and how thick and what material for boat x length or boat y displacement.
Heat and sharp angles are to be avoided. Easier said than done.
I have an eye just above waterline at the stem. I’ve built a boat with two heavy bronze short chainplates with a bolt and toggle right at this spot. Ballistic strong.
Now you can use a trick I’ve seen in Alaska. The long, long, snubber starts at the junction of the anchor chain and a #2 low drag float. It turns over a good size block at the waterline and comes up parallel to the stem to the deck. Chafe gear at the deck. When wind or waves push the boat aft, the bow is not forced down as much and the vessel tends to climb over rather than plunge into the wave.
The chain, or rode act as a safety. The snubber doing all the work.
Too springy and you yo-yo all over the place. Too stiff, you slam. There was a bungee thing I think Hazlet...something like that...just for moorings. I think it came from oceanography equipment. Try contacting some of the harbormasters where they really don’t have a harbor. LOL.
Elk hide, baseball stitch, lanolin, good needles...it works and is fun.
Happy trails to you.
Mark, a memory challenged manatee

[Cadence]

I hadn't read all of the posts. If the chaffing is at the chocks had you considered the chocks not the line?

[Jetx]

Originally Posted by chris95040

It seems like a newish strategy so I’m nervous about any unexpected failure mode (UV exposure?) that isn’t encountered when only using it for storms.

Any size dyneema that doesn’t look “too small” to the eye is going to have gobs of surplus strength, so UV damage (outer fibers only) should not be an issue.

Google “New England Ropes cyclone pendant“ to buy them premade.

[chris95040]

I’m sold on the concept of a dyneema leader but I share hlev00’s concern about the dyneema cutting through the nylon.

The cyclone seems to want to be arranged as a Y (bridle) around a single nylon pendant. That’s not exactly what I want, I’d prefer two completely separate pendants, each with their own single dyneema leader. I’m thinking each would be 15’ of 1” nylon attached to 5’ of 0.75” dyneema. I wonder what the strongest way to attach the dyneema to the nylon would be.

Presently I just drape my spliced eye around my bow cleat (as pictured in original post). Is this what I’d do with the dyneema eye or is there some fancier fastening to the cleat that would be better?