Rolling Hitch on Snubber

[Bash]

Originally Posted by Andrew Troup

Those who claim that a chain catenary cannot work if the wind force is enough to straighten the chain are either thinking of roadstead waves or (more often) simply misunderstanding how catenary absorbs energy. By the time it's straight, the chain (if sufficiently heavy for the energy input) had done its job and prevented the snub.

Agreed! I've argued that the myth of ineffective chain catenary in any breeze over 20 knots has been propagated by anchor manufacturers themselves, largely because they gain by having cruisers invest less in chain and more in anchors. (Especially when we buy larger and larger anchors.)

[s/v Jedi]

Originally Posted by Cotemar

I know some of you guys do not think these rubber snubbers are any good, but a few cruisers at my marina have been using them for 10 years without a failure, so time will tell if it will work in my boat.

10 years?! Not even stainless steel wire is good for that long according to the experts!

This simply means that they hardly anchor. When I state 2 years, it means 650+ days at anchor full time.

[estarzinger]

One other data point on the actual loads I had . . . .my windless bogs down at 3200lbs, but it had no problem at all pulling chain in (Which I did to put the replacement snubber on), not even noticeably slowed down, even in the 'peak load wave moments'. That would seem to be consistent with my 'less than 2000lbs' estimate.

[colemj]

Originally Posted by Bash

Agreed! I've argued that the myth of ineffective chain catenary in any breeze over 20 knots has been propagated by anchor manufacturers themselves, largely because they gain by having cruisers invest less in chain and more in anchors. (Especially when we buy larger and larger anchors.)

There are those of us who regularly anchor in 6' of water, where chain cantenary does us little good at all. Ah, to be a deep draft mono on the Pacific coast...

No, wait, nevermind

Mark

[Cotemar]

Originally Posted by s/v Jedi

10 years?! Not even stainless steel wire is good for that long according to the experts!

This simply means that they hardly anchor. When I state 2 years, it means 650+ days at anchor full time.

We only get a 6 month seasons up here in the North East US,

Your 2 years full time cruising would be a good working time frame.

The rubber snubbers may not even give me that much time, but I am willing to give them a try, because even if they do fail they just hang down and the 3-strand nylon line will just have to work harder. I just never want a strong snatch load to break my snubber bridal and then let a taught chain drag on my bow hulls.

Thanks for all your soft shackle info and links.
I now have a few Soft Shackles to try as my snubber bridal to chain connector which really needed an upgrade.

[s/v Jedi]

Originally Posted by Cotemar

We only get a 6 month seasons up here in the North East US,

Your 2 years full time cruising would be a good working time frame.

The rubber snubbers may not even give me that much time, but I am willing to give them a try, because even if they do fail they just hang down and the 3-strand nylon line will just have to work harder. I just never want a strong snatch load to break my snubber bridal and then let a taught chain drag on my bow hulls.

Thanks for all your soft shackle info and links.
I now have a few Soft Shackles to try as my snubber bridal to chain connector which really needed an upgrade.

There are also stainless steel spring devices that work much like those rubber snubbers. With a little help from Boeshield T9 they should last a long time.

[colemj]

Those spring things might be a bit rough on the topsides.

Mark

[wsmurdoch]

We are anchored today in Marsh Harbour, Bahamas. The water depth is 2m, tide range is 1m, water to bow is 1m, 80ft of 5/16 BBB chain is out with a 45lb Bruce on the end. The rope is 7/16 nylon and of questionable pedigree. It has a stainless hook on it and will not reach the bottom. The rubber mooring snubber was a freebee. It adds a bit of stretch that the short rope does not have. The rope passes through 4ft or so of 4" polyester webbing chafe protection sewn into a tube. We have used it for maybe 4 years. While I have better snubbers, this is the one we have used most often. In fact, this year I have used no other. My guess is that it has 300+ nights at anchor in the Bahamas on it along with another 200 nights between North Carolina and Florida.



Good for hurricanes -- no. Quiet, easy to set and retrieve, cheap, satisfactory for its intended purpose -- yes. Does the hook stay on when it is supposed to and shake off when it is not -- yes. Will the black rubber last 10 years -- who knows.

www.irish-eyes-to-the-bahamas.blogspot.com

[s/v Jedi]

Originally Posted by wsmurdoch

We are anchored today in Marsh Harbour, Bahamas. The water depth is 2m, tide range is 1m, water to bow is 1m, 80ft of 5/16 BBB chain is out with a 45lb Bruce on the end. The rope is 7/16 nylon and of questionable pedigree. It has a stainless hook on it and will not reach the bottom. The rubber mooring snubber was a freebee. It adds a bit of stretch that the short rope does not have. The rope passes through 4ft or so of 4" polyester webbing chafe protection sewn into a tube. We have used it for maybe 4 years. While I have better snubbers, this is the one we have used most often. In fact, this year I have used no other. My guess is that it has 300+ nights at anchor in the Bahamas on it along with another 200 nights between North Carolina and Florida.

Good for hurricanes -- no. Quiet, easy to set and retrieve, cheap, satisfactory for its intended purpose -- yes. Does the hook stay on when it is supposed to and shake off when it is not -- yes. Will the black rubber last 10 years -- who knows.

www.irish-eyes-to-the-bahamas.blogspot.com

Your snubber looks good to me, but the slack loop of chain is not nearly big enough. The snubber has much more stretch than that.

[estarzinger]

Originally Posted by Bash

For climbing applications, the only splicing instruction is "don't do it."

Originally Posted by s/v Jedi

the negative I see wth climbing rope is the difficulty splicing it

Factually, related to splicing climbing line . . . New England Ropes has instructions for three splicing methods. The strongest is called the "Heavy Duty Kermantle Eye Splice".

I made four of them today. Like most double braid splices it is harder in 'old' line than brand new line. In new line, I found it just a tad easier than the typical marine double braid splice (the splice is just a bit easier to drive home at the end).

So, I would say that splicing is not in fact a barrier/downside to using kermantle.

[Panope]

Originally Posted by colemj

There are those of us who regularly anchor in 6' of water, where chain cantenary does us little good at all. Ah, to be a deep draft mono on the Pacific coast...

No, wait, nevermind

Mark

I think this is a very important point that is often overlooked in catenary/snubber discussions.

I think it should be emphasized that the big difference between deep water anchoring and shallow water anchoring (with regard to catenary effectiveness) is not the amount of chain. In shallow water no amount of chain will provide effective catenary because the bottom has already "lifted" the chain to a nearly "bar tight" position.

Imagine having 1000 feet of chain lying on the bottom in 6 feet of water. This chain is already 99% strait and as very little of the energy absorbing power that Andrew described previously.

Steve

[wsmurdoch]

Originally Posted by s/v Jedi

Your snubber looks good to me, but the slack loop of chain is not nearly big enough. The snubber has much more stretch than that.

You are quite right. I just pulled in the slack and measured it. It was only 22". I'm learning.

[Andrew Troup]

Originally Posted by s/v Jedi

Your snubber looks good to me, but the slack loop of chain is not nearly big enough. The snubber has much more stretch than that.

I personally think that the slack should not be based on how much the snubber can stretch, but on how much you NEED it to stretch.

And the latter will preferably be a smallish proportion of the former.

Unless conditions were likely to get rapidly worse and/or the boat would be unattended, I would personally err on the side of less slack, and pay out a bit more every time there was a severe snub.

[Andrew Troup]

Evans

I wasn't meaning to suggest there has been a single answer

Perhaps there are two broad groups: if there's a 'consensus' in one group, it's that rolling hitches have always worked for them and they propose to continue on that basis

and it seems to me there's an apparent 'truce' whereby the other group have exhausted themselves by discussion, and hostilities have been (at least for the time being) suspended.

What members of the second group seems to have in common that they're not entirely comfortable with direct attachment of the snubber to the chain and (in most cases) are following your quest with some interest.

[thinwater]

Originally Posted by Andrew Troup

Evans

I wasn't meaning to suggest there has been a single answer

Perhaps there are two broad groups: if there's a 'consensus' in one group, it's that rolling hitches have always worked for them and they propose to continue on that basis

and it seems to me there's an apparent 'truce' whereby the other group have exhausted themselves by discussion, and hostilities have been (at least for the time being) suspended.

What members of the second group seems to have in common that they're not entirely comfortable with direct attachment of the snubber to the chain and (in most cases) are following your quest with some interest.

Good points. The other thing, over 300 posts into this thread, is that most folks have THE ANSWER, which is interesting because there are multiple questions:

• Deep water, high winds. Chain will do most of the work, the snubber should be strong but can be on the short side.
• Open roadstead, waves in shallow water are hazardous. Better have a lot of strong snubber or a strong nylon rode. Not enough chain out to work, so the snubber has to stretch enough for the rise and fall of waves. May have only 75 feet of rode out, so light chain is easily straitened. Basically, a bad place to anchor, perhaps untenable. Cats and small boats can be tempted into these places.
• Poor holding. A fair a mount of very soft snubber will help keep the anchor in by keeping everything soft. Chain helps slow the affect of wind shifts.

And I'm sure there are more. Personally, I have 2 bridles, one much thinner than the other. The thin one is for general use in Chesapeake mud without significant waves. It wouldn't last in a rough place, but it keeps me put in soft stuff. Horses for courses.