Dyneema sleeve to protect the snubber

[chouliha]

This maybe beyond the general OP statement but here goes.

We have something like 4500+ nights at anchor over the past 35-40 years. Have tried many different types of setups. Here is what works for us. We have a 7’ piece of heavy dynema that runs from the cleat over the bow roller and then attaches to a piece of 3 strand using a double sheet bend. Attaching the 3 strand to the anchor chain with a camel hitch.

Why use this method?

1. Using the dynema first eliminates all chafe because there is no stretch. We do not use any chafe gear. Same piece of dynema is 6+ years of continuous cruising.
2. all the stretch happens beyond the boat.
3. We have never had any issues with the camel hitch coming undone or slipping even with winds of 60 knots.
4. We have used chain hooks in the past but they either fell off or got so rusty we discarded them. It required a thimble to be backspliced onto the 3 strand. We tried them for maybe 100 nights at anchor so gave them a decent test before deciding we did not like them

This idea was provided by Evan Stargazer.

I am not saying this is your answer but only what works for us.

Good luck with your choice

Chuck
Jacaranda
Mo’orea

[thinwater]

Originally Posted by chouliha

This maybe beyond the general OP statement but here goes.

We have something like 4500+ nights at anchor over the past 35-40 years. Have tried many different types of setups. Here is what works for us. We have a 7’ piece of heavy dynema that runs from the cleat over the bow roller and then attaches to a piece of 3 strand using a double sheet bend. Attaching the 3 strand to the anchor chain with a camel hitch.

Why use this method?

1. Using the dynema first eliminates all chafe because there is no stretch. We do not use any chafe gear. Same piece of dynema is 6+ years of continuous cruising.
2. all the stretch happens beyond the boat.
3. We have never had any issues with the camel hitch coming undone or slipping even with winds of 60 knots.
4. We have used chain hooks in the past but they either fell off or got so rusty we discarded them. It required a thimble to be backspliced onto the 3 strand. We tried them for maybe 100 nights at anchor so gave them a decent test before deciding we did not like them

This idea was provided by Evan Stargazer.

I am not saying this is your answer but only what works for us.

Good luck with your choice

Chuck
Jacaranda
Mo’orea

A camel hitch is FAR more secure than a rolling hitch and no more trouble to tie. I have used it in place of rolling hitches for many years.


Evan's a smart guy, and he tests his ideas.

[gauvins]

Originally Posted by chouliha

We have a 7’ piece of heavy dynema that runs from the cleat over the bow roller and then attaches to a piece of 3 strand using a double sheet bend. Attaching the 3 strand to the anchor chain with a camel hitch.

Interesting. Two questions.

1. What is the length of your 3-strand?

2. I assume that your snubber is of fixed length, but I may have the wrong mental picture. Or can you put more of a snubber if needed, without having to pull it on deck?

[Dockhead]

Originally Posted by thinwater

A camel hitch is FAR more secure than a rolling hitch and no more trouble to tie. I have used it in place of rolling hitches for many years.


Evan's a smart guy, and he tests his ideas.

Camel hitch is fine, but rolling hitch is more or less absolutely secure when tied to chain. I've never had one fall off in 30+ years of cruising. I sometimes use three turns instead of two if I expect the snubber to be under a lot of load.



Tying to chain means nothing slips. It behaves practically like a splice. It's so easy and so fast that I can't imagine what advantage a chain hook provides. How much time would be saved by a chain hook -- maybe 3 seconds at most?

[chouliha]

Originally Posted by gauvins

Interesting. Two questions.

1. What is the length of your 3-strand?

2. I assume that your snubber is of fixed length, but I may have the wrong mental picture. Or can you put more of a snubber if needed, without having to pull it on deck?

I have 2 setups. The first is for anchoring in normal conditions which is about 98% of the time and the 3 strand is 8-10’ long. The second setup is for storm conditions and the 3 strand is 25-30’ in length.

Both snubbers are setup as separate systems. When conditions warrant I dig out the storm snubber and attach it. It has the dynema and 3 strand already attached together.

They can not be adjusted once attached.

I had Evans write up bookmarked from this forum but it appears he may have taken his website down along with his various articles.

[gauvins]

Understood.

I very much like the basic idea. But am "committed" (dyneema cover is traveling on DHL as I write this ). Benefit of a cover system might be that it'll be possible to go from nice and quiet to not so nice by releasing the full length of the snubber.

Take care

[conachair]

Originally Posted by chouliha

I had Evans write up bookmarked from this forum but it appears he may have taken his website down along with his various articles.

Might be in here somewhere----

https://web.archive.org/web/20160327...systems.htm#11
https://web.archive.org/web/20160323...df/snubber.pdf

[gauvins]

Originally Posted by conachair

Might be in here somewhere----

https://web.archive.org/web/20160327...systems.htm#11
https://web.archive.org/web/20160323...df/snubber.pdf

Yes. Thanks for the link. From which there's another link to a PDF describing in a fair amount of detail how he went about this...

Two things. First, and rather importantly, he mentions that putting out more snubber can be done by securing another mooring line to the bitter end of the dyneema rope. That additional length would then be secured to a point on deck. Second, there's no argument for or against dyneema covers vs a dyneema rope. He notes that dyneema ropes have a tendency to slide on tackles such that he suggests an alternative to the usual way in which lines are secured. I'll take that as a point in favor of covers. A small point, admittedly

[conachair]

Just to add to the mix....

This setup has yet to be tested in anger but cautiously confident it will work OK no doubt with a few tweaks along the way.

No chafe, the elastic part of the snubber won't touch anything, short length of dyneema thick goes through the bow roller. The nylon will go through a decent pulley where it diverts next to the cockpit.
No need to bring in a load of chain to get to the snubber connection if you want to let more chain out.
No slimy snubber that's been in the water for ages with a few jelly fish tentacles to deal with.

[chouliha]

Originally Posted by conachair

Might be in here somewhere----

https://web.archive.org/web/20160327...systems.htm#11
https://web.archive.org/web/20160323...df/snubber.pdf

Thanks for digging this up. I have saved the pdf for future reference.

Another thing I forgot to add is how quiet this system is. Previously we would have a very noisy time in windy conditions before adding the dynema as we sleep in the V berth not to far away from the roller. Listening to the movement of the snubber either thru the chocks or over the bow roller with chain noise was completely eliminated by using the piece of dynema.

Using a dynema sleeve will certainly help with chafe but not stop the stretch over the chock or bow roller.

Just something to think about

Cheers

Chuck

[admiralslater]

The first season on our Outremer 45 we used a chain hook to attach to our bridles each of wich is 25 feet of .625 three strand nylon . The bridle was fine but the hook fell off when going through the roller and if the bridle hit the bottom ,both annoying.
The next year my father ,(the super splicer )made me a soft shacle out of 7 mil dyneema. I pass it through the chain and it never comes apart . After 3 years there was no real sign of chafe. After a week of very gusty and strong winds it finally let go .
On inspection it appears that the rope overheated and did not chafe through.
I had my 85 year old dad make a new one out of larger rope but this is difficult to pass through the links . I saw Thin waters post on the prussic knot and Voila I had my answer. These year my dad made me a 2 foot loop which i will use as a prusic knot and attach with the soft shackle.
As for the snubber ,usually the bridle is enough . On occasion I add my 18 mil 12 plait dock lines to the end of the bridle lines and give my self 50 foot long snubbers . This really dampens the shock loads.

[thinwater]

Originally Posted by Dockhead

...Tying to chain means nothing slips. It behaves practically like a splice. ...

No, no, no. I've done the testing and watched rolling hitches slip at high load, one after another, sometimes 5 in a row. Evan, among many others, have had them slip cruising. Finally, it is absolutely weaker than a splice, like any knot. These to, are facts.


I believe you have been lucky, with just the right combination of chain and rope. It never slipped for you. I believe that. However, the perfect nature of a rolling hitch is not defensible in the broader world. Too many cruisers say otherwise.



---



BTW, a camel hitch is a rolling hitch with the last turn reversed. It does not slip on chain.

[gauvins]

Originally Posted by thinwater

I've done the testing [...]l

Somewhat unrelated - any opinion on the snubber's characteristics? One post in this thread mentioned the yoyo effect (i.e. the snubber elongates, then retracts. At some point there's little tension at the bow. The boat yaws (is there a verb?) and the cycle starts again. Actually, happens to me with or without snubber).

I've read quite a bit on the topic but couldn't find much regarding the mechanics of snubbers, beyond the obvious.

In particular, my understanding is that snubbers are meant to deal with surge shocks, not with steady pull. Essentially waves. In an ideal world, the snubber would store the energy generated when the bow climbs a wave, and restore it when it goes down. When conditions are mild, a chain's catenary does it. When the wind picks up, the chain gets tight and there's no more catenary, so we depend on the snubber.

We read about snubbers length, but rarely about how much energy they can store, and how quickly/slowly they'll release it. I understand that this is complex and not really critical, but having time to spare, might as well learn something

-- edit --

There's this https://www.pbo.co.uk/gear/pbo-teste...snubbers-45131

[JayH]

Originally Posted by gauvins

1. Risk of user error. We're summer sailors.
2. Not so easy with large diameter rope and limited clearance between the deck and chain
3. Execution speed could be an issue. We sometimes have just a few seconds to secure the chain while the boat backs up to set the anchor. Would not be fun to be caught with your hand under the chain when it gets loaded.



We have two. Using the roller in line (i.e. where the chain goes) is precisely why I want to splice a cover. Using the other roller would mean going over the bow to secure the line to the chain.

Execution speed is a biggie for me. I want the bridle on and off the chain as fast as possible so the boat doesn't lose momentum. We used to use rolling hitches, but have recently switched to a dyneema climbing sling doubled, then luggage tagged on to the chain, then the bridles clip to the sling. It's fast, easy, and strong.

[jmh2002]

Originally Posted by gauvins

Typically we drop 3:1, secure the chain to our Samson post on 1M of rope to relieve the windlass. Engine in reverse mid to full throttle depending on the circumstances. (Mostly mid). The anchor sets. We wait a bit until the boat gets into position. Then release more chain. Up to 5:1 or so.

Typically we keep track using our chart plotter. If the boat makes forward progress when the engine goes into neutral, it means that the anchor was properly set. No feeling involved.

I don't think that is best practice since most boats will 'make forward progress' when the engine goes into neutral' simply from the catenary effect of the chain. It's not related to whether the anchor is properly set or not.

Best practice is to use sight lines from onboard while the engine is still at a constant rpm in reverse and the boat has settled against the anchor, chain, wind, sea, etc, and check that a constant bearing is maintained (not via a gps/chart plotter...).

When setting the anchor using the above technique the chain will be 'at full stretch' (tight). After going into neutral the boat will move forward from the catenary effect and thereafter (wind strength dependant) move back again to an average position as the boat settles against the wind and chain.

Now you can use the gps/plotter to track this average position if you wish, and of course it's useful to have an automatic alarm, etc (these days even sent to your mobile phone while you are ashore ), but the sightlines still work as the fastest indicator.

Additionally I'm surprised to hear of this practice of setting at a certain scope and thereafter letting out more chain out again later? It seems unnecessary, unless the conditions have changed. In general I have normally just set directly at the scope intended / needed to be used and left it at that.

But on difficult bottoms it may be necessary to do the opposite and set at a longer scope than required, to get the anchor to penetrate and bury (maybe through weed or something for example), but once properly set thereafter you can shorten up to the appropriate scope for the anchorage and conditions.

An initial short scope can often cause the anchor to skip across the bottom instead of burying and setting.