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Old 10-20-2015, 07:16 AM   #81
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Quote:
Originally Posted by Capt.Bill11 View Post
I think you used to be able to buy them on Silk Road.

Seriously though, some of the high end snap shackles have a high working load but as you mentioned I don't know if they will fit in a chain link.
I use a very substantial one of these, which just snuggly fits over 10mm chain...

https://www.whitworths.com.au/main_i...AbsolutePage=1
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Old 10-20-2015, 09:50 AM   #82
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Originally Posted by caltexflanc View Post
And I'm still interested in where you find a snap shackle or snap hook that will fit in a chain link and match the working load. The various high end snubber riggers such as Rope Inc and Ultra haven't figured that one out yet either, nor have the windlass guys.
I think you can get close as long as it isn't galvanized, which is a non starter for me. Soft shackles are stronger than the chain so I still can't see the advantage of a hook or hard shackle. A 3/16" soft shackle made correctly of Dyneema has a breaking strength of around 12,000#. The breaking strength of 1/4" G4 is 7500#. Just too easy and too strong not to use, IMO.

This is a nice guide on making your own, for those interested:

http://www.bethandevans.com/pdf/improvedsoftshackle.pdf
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Old 10-20-2015, 09:55 AM   #83
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Originally Posted by sunchaser View Post
Last month we were anchored in near gale force winds which lasted for a few hours. Our V bridle snubber was stretched "fairly" taut while hooked onto the 3/8 chain. Would not the chain be equally taut whether the snubber is there or not?
When chain is taut, it has no more stretch. When a snubber is taut it may only have begun to stretch. Since the force of wind/wave is reduced proportionally to the distance over which the force is applied to the vessel, a snub line will significantly reduce the snatch load on the system. IMO, while bridles will quiet the chain and will help a bit to reduce loads, they are usually far too short to help as much as a single line 30' or so long.
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Old 10-20-2015, 10:29 AM   #84
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Quote:
Originally Posted by Peter B View Post
I use a very substantial one of these, which just snuggly fits over 10mm chain...

https://www.whitworths.com.au/main_i...AbsolutePage=1
That's not a snap hook or snap shackle.

Dynema soft shackles are cool, but rigging one to/through a chain link and whatever is at the end of the snubbing line is way too much fine motor skill work for me vs simply dropping a hook on the chain or even tying a rolling hitch for that matter.
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Old 10-20-2015, 11:05 AM   #85
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Originally Posted by Delfin View Post
When chain is taut, it has no more stretch. When a snubber is taut it may only have begun to stretch. Since the force of wind/wave is reduced proportionally to the distance over which the force is applied to the vessel, a snub line will significantly reduce the snatch load on the system. IMO, while bridles will quiet the chain and will help a bit to reduce loads, they are usually far too short to help as much as a single line 30' or so long.
I could be wrong but I think he's just trying to point out that with or without a snubber the chain will go taught once the wind is strong enough.

But with a snubber you have still have shock absorption. Where as with out all the shock loads are transferred to the boat and anchor.
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Old 10-20-2015, 11:06 AM   #86
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Quote:
Originally Posted by Delfin View Post
When chain is taut, it has no more stretch. When a snubber is taut it may only have begun to stretch. Since the force of wind/wave is reduced proportionally to the distance over which the force is applied to the vessel, a snub line will significantly reduce the snatch load on the system. IMO, while bridles will quiet the chain and will help a bit to reduce loads, they are usually far too short to help as much as a single line 30' or so long.

I agree. But how long the snubber to be of any shock loading use?

So to keep the balloon pricked here, yes Muir and others sell snubbers, gear and equipment to protect the (weak and flimsy) windlass and charge dearly for their off the shelf connectors. But nowhere have I seen tables, charts and data to support "this is how long your snubber needs to be to keep your anchor from dislodging when the wind starts blowing."

It would appear we are back to the not so novel concept of oversizing the anchor to deal with big blows and the unknown snubber stretch with ensuing benefits concept. Or have a combination rope and chain rode with a big anchor then all bases whether real or imagined are theoretically covered.


So, how long are your snubbers?
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Old 10-20-2015, 11:14 AM   #87
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"Or have a combination rope and chain rode with a big anchor then all bases whether real or imagined are theoretically covered."
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Old 10-20-2015, 12:08 PM   #88
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Originally Posted by sunchaser View Post
I agree. But how long the snubber to be of any shock loading use?

So to keep the balloon pricked here, yes Muir and others sell snubbers, gear and equipment to protect the (weak and flimsy) windlass and charge dearly for their off the shelf connectors. But nowhere have I seen tables, charts and data to support "this is how long your snubber needs to be to keep your anchor from dislodging when the wind starts blowing."

It would appear we are back to the not so novel concept of oversizing the anchor to deal with big blows and the unknown snubber stretch with ensuing benefits concept. Or have a combination rope and chain rode with a big anchor then all bases whether real or imagined are theoretically covered.


So, how long are your snubbers?

Most people use snubbers that are way to short IMO. The easiest way to do this is to use a snubber that is at least 25 feet long. Tie it off short if you wish in most case. But then you can let it out in the event the wind pipes up or a storm is predicted, to give you the extra stretch you need.

I should add put an eye in the vessel end of the snubber big enough to slip over your cleat or post to give you the longest length for the most stretch.

And for a snubber you want to use line with a good amount of elasticity to it, don't over size it and use chafe gear.
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Old 10-20-2015, 12:44 PM   #89
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So, how long are your snubbers?
We follow the advice of a several long-time cruisers of this area (power and sail) in our boating club with regards to using a snubber. We use a V-bridle and we let the bridle out until the chain gripper is some 8 to 10 feet under the surface of the water. Once the bridle is deployed we let more chain out until we have a loop hanging down some 15 feet or more between the pulpit roller and the chain gripper.

This configuration helps lower the angle of pull on the anchor but of course enough of a blow will still pull the catenary out of the chain between the anchor and the chain gripper.

The fact we use a snubber has no effect on the size of anchor or the scope we use.
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Old 10-20-2015, 01:23 PM   #90
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The snubber I use is 1/2 dia 3 strand nylon and just over 20 feet long.
That would put it about 15 feet off the bow roller.
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Old 10-20-2015, 02:19 PM   #91
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You can find out the working load, capacity and stretch statistics of various sizes and designs and material of lines if you want to get all pedantic and paranoid about it. I use three strand nylon sized as if it was going to be anchor line, since under bad conditions, that's what it will be. Even on a double bridle, the boat will lay to one line or the other much of the time, and more so depending on boat design, and wind vs swell vs current. I went with about 25 feet myself. Everything went hunky dory in sustained 45knt, plus an hour or so at 60+ with gusts to 80 from a microcell.

I like all chain for a wide variety of reasons, ergo, I snub.

If you are a fair weather anchorer do whatever you like. The rodes on my 13' Whaler are chain/rope combos.
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Old 10-20-2015, 05:08 PM   #92
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Quote:
Originally Posted by sunchaser View Post
I agree. But how long the snubber to be of any shock loading use?

So to keep the balloon pricked here, yes Muir and others sell snubbers, gear and equipment to protect the (weak and flimsy) windlass and charge dearly for their off the shelf connectors. But nowhere have I seen tables, charts and data to support "this is how long your snubber needs to be to keep your anchor from dislodging when the wind starts blowing."

It would appear we are back to the not so novel concept of oversizing the anchor to deal with big blows and the unknown snubber stretch with ensuing benefits concept. Or have a combination rope and chain rode with a big anchor then all bases whether real or imagined are theoretically covered.


So, how long are your snubbers?
Tom, while I couldn't find the reference now, I recollect reading in a technical paper on mooring lines for very large ships that a good rule of thumb is a reduction calculated by dividing the shock load by feet of stretch. So the question on how long a snub line should be is basically a function of getting as much stretch as possible, limited by a line size appropriate for the load limits of the chain used. If the shock load in gusts is 10,000# (quite a gust), then 4 feet of stretch reduces that load by 75%. 15% stretch is pretty typical for nylon lines without over stressing them, so if you want 4 feet of stretch you need around 30 feet of snubber. I assume that is why 30' is the most typical recommendation I recall seeing. This is also why I don't see all that much shock load reduction benefit from bridles, because they are generally only a few feet long. Naturally, if you have all rode, you have all snubber.

I use a 30'. The snubber is made of a short bit of dyneema mated to 5/8" nylon brait with an Ultra snubber that basically just acts as a visible indicator of load. The more the rubber is stretched, the greater the loading on the snubber. It is joined with a Plasma soft shackle that takes me about, oh, 3 seconds to attach to the chain, is stronger than the chain, and can't fall off. The whole line feeds out over a roller above the chain roller so it is always fairly led.
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