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Old 10-06-2021, 14:38   #151
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Re: Dragging my Rocna - Is my technique at fault?

Thanks Steve! Yes I have dived in a place where the bottom had a thick layer of gelatinous ooze and though I didn’t see an anchor there I can imagine that ANY anchor would find it hard to get a bite to begin its dive UNLESS it is heavy enough to sink through that layer to find something to dig into. Pretty tough to get a photo there, who’s up for the challenge?
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Old Yesterday, 08:41   #152
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Re: Dragging my Rocna - Is my technique at fault?

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I am struggling, too, because given this sentence, could you help me understand what your chain is connected to if the snubber breaks? As last we left it, the chain was wrapped around your cleat, but you seem to have agreed that either a chain stopper or at least a strop is something you agree with. Please help us understand where you're coming from here. Thx.
Right sorry. Assume chain snubbed with 20' line cleated off properly, chain is on windlass which afaict does not have a "free fall" mode.

What I'm struggling with is the strop, which appears to be essentially a very short version of my snubber ie a length of line with a hook on the end, and what it solves. Help me think this through.

So, if the snubber breaks in our hypothetical storm situation, wouldn't the strop?

And even if it doesn't, once the strop is cut or untied, I'm left with chain on windlass. In order to get out of the situation I have to unload the windlass, which means sailing or motoring forward.

If its a howling gale, can't sail, water full of sand from storm coming in to anchorage so engines failing left and right (similar to the Mexican disaster a number of years ago), my only choice is ride it out or dump the chain and run. How does the strop help me here?

Just searching for knowledge and understanding.
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Old Yesterday, 08:43   #153
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Re: Dragging my Rocna - Is my technique at fault?

The strop doesn't need to be stretchy, so it can be much stronger and bigger than your snubber. But yes, I agree with the idea that if conditions are so bad that you can't safely un-anchor yourself (especially short of a dump and run), leaving isn't a good idea anyway.
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Old Yesterday, 08:58   #154
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Re: Dragging my Rocna - Is my technique at fault?

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Right sorry. Assume chain snubbed with 20' line cleated off properly, chain is on windlass which afaict does not have a "free fall" mode.

What I'm struggling with is the strop, which appears to be essentially a very short version of my snubber ie a length of line with a hook on the end, and what it solves. Help me think this through.

So, if the snubber breaks in our hypothetical storm situation, wouldn't the strop?

And even if it doesn't, once the strop is cut or untied, I'm left with chain on windlass. In order to get out of the situation I have to unload the windlass, which means sailing or motoring forward.

If its a howling gale, can't sail, water full of sand from storm coming in to anchorage so engines failing left and right (similar to the Mexican disaster a number of years ago), my only choice is ride it out or dump the chain and run. How does the strop help me here?

Just searching for knowledge and understanding.

Hi, again, I think you're looking at this backwards. Instead of thinking of storm conditions, we are trying to get you to understand normal conditions, where even a 12 knot breeze can push your boat back.


The bridal is to avoid the chain from snatching against your bow roller.


The chain stop (or strop as you call it) is to unload the windlass completely. This can be all right on the foredeck.


It's that simple.
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Old Yesterday, 10:24   #155
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Re: Dragging my Rocna - Is my technique at fault?

Oh, no, I did it!!!


Bridle...sheez. No excuse.
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Old Yesterday, 10:25   #156
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Re: Dragging my Rocna - Is my technique at fault?

If snubber breaks then snubber either grinded away until destroyed on radii at gunnel or pitch is strong and line sheered.
Chain on a stronger pitch (bow pulpit) ain't going to last long before snap.

Protect your snubbers, they protect you.
I don't know how cruisers your size do such, I'm learning to learn too.
Basically maintain a degree of drag and lift on chain is principal to drag on shank and lift to spring then vessel attachment being line to spring via stretch.
Chain doesn't stretch, it'll accelerate to taunt then hit a single link with momentum gained from rode system. Hence length to lift. Short scope is line to reduce acceleration of rode which will otherwise simply snap if attached to pulpit without enough dampening.
Dampening; chain lift, line gift.
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Old Yesterday, 11:23   #157
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Re: Dragging my Rocna - Is my technique at fault?

Breaking a snubber I feel is like breaking an anchor chain. It is pretty unlikely in any condition that you had any hope of making it through unless the snubber line or chain had a problem to start with.

I know I was just looking up rope anchor sizes for boat. The recommended size 3-strand nylon has a breaking strength 4 times that of my chain.
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Old Yesterday, 11:25   #158
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Re: Dragging my Rocna - Is my technique at fault?

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Breaking a snubber I feel is like breaking an anchor chain. It is pretty unlikely in any condition that you had any hope of making it through unless the snubber line or chain had a problem to start with.

I know I was just looking up rope anchor sizes for boat. The recommended size 3-strand nylon has a breaking strength 4 times that of my chain.

Usually it's not the actual breaking strength that becomes a problem. It's the repeated cycling loads. If you're cycling the line to more than about 20% of its breaking load, it's going to have a fairly short lifespan.
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Old Yesterday, 12:59   #159
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Re: Dragging my Rocna - Is my technique at fault?

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Oh, no, I did it!!!


Bridle...sheez. No excuse.
Maybe this is why the mods havenít promoted you up yet even with all your wisdom
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Old Yesterday, 14:30   #160
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Re: Dragging my Rocna - Is my technique at fault?

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Usually it's not the actual breaking strength that becomes a problem. It's the repeated cycling loads. If you're cycling the line to more than about 20% of its breaking load, it's going to have a fairly short lifespan.
Testing I believe acturally says it is the heat from the cycling.
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Old Yesterday, 14:41   #161
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Re: Dragging my Rocna - Is my technique at fault?

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Originally Posted by sailorboy1 View Post
Breaking a snubber I feel is like breaking an anchor chain. It is pretty unlikely in any condition that you had any hope of making it through unless the snubber line or chain had a problem to start with.

I know I was just looking up rope anchor sizes for boat. The recommended size 3-strand nylon has a breaking strength 4 times that of my chain.


I never have personally but have heard of snapping snubbers many times.

To the others- use a dyneema strop to a chain hook if need be instead of a chain stopper if not installed. You can cut it to get free but it will rip out the cleat before it breaks

I always rig it as a backup to my snubber so if snubber fails the windlass is still protected
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Old Yesterday, 16:58   #162
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Re: Dragging my Rocna - Is my technique at fault?

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...
.............................................


I always rig it as a backup to my snubber so if snubber fails the windlass is still protected



Many thx, succinct answer to the OP's last question. Perfect.
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Old Yesterday, 17:52   #163
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Re: Dragging my Rocna - Is my technique at fault?

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Testing I believe acturally says it is the heat from the cycling.

Yeah, internal heating of the line is absolutely a concern for failure when cycling to a large portion of maximum strength.
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Old Today, 00:25   #164
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Re: Dragging my Rocna - Is my technique at fault?

Quote:
Originally Posted by sailorboy1 View Post
Breaking a snubber I feel is like breaking an anchor chain. It is pretty unlikely in any condition that you had any hope of making it through unless the snubber line or chain had a problem to start with.

I know I was just looking up rope anchor sizes for boat. The recommended size 3-strand nylon has a breaking strength 4 times that of my chain.
What size snubber and chain do you use?

The snubber needs to stretch to do its job. To keep the length practical it is normally weaker than the chain even when new. Most boats use a snubber diameter smaller than the recommended rope rode size.

Nylon loses strength when wet, when exposed to UV, with stretch cycles and chafe so in practice it likely to be significantly weaker than the chain.

Snubbers can and do break, typically in terrible conditions when the stretch is most needed. Good chafe protection (for example, we use a section of Dyneema where the snubber passes over the bow roller) as well as periodic replacement helps, but we have still broken quite a few over the years. They break with an enormous bang, so you will be alerted and can remedy the situation, but it worth considering steps to prevent a high shock load being placed on the windlass. A chainstopper or short strop are typical solutions that easily avoid this issue. Some cruisers even go to the trouble of rigging a second long snubber in severe conditions, so if the primary snubber breaks no stretch is lost even briefly.
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Old Today, 02:59   #165
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Re: Dragging my Rocna - Is my technique at fault?

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Usually it's not the actual breaking strength that becomes a problem. It's the repeated cycling loads. If you're cycling the line to more than about 20% of its breaking load, it's going to have a fairly short lifespan.
Yes.

Chain brought to taunt is angry chain.
She ; the vessel is trying to break free.

Many times, dragging anchors have been replaced with a much stronger crown. But then shank will lift which is suspect as original problem and chain will snap. Her freedom goes from no purchase to snap chain to simply breaking free.
Even in light conditions, just a rouge wave from a passing SWC can pitch fast , short and direct.

To remove fast progression of chain from loose to tight, another method is.
Multiple weights of chain.
Heaviest on shank eye, through to lightest on less depthed of rode.
This enables a progressional tension of rode to be obtained. By the time she's lifted the light, then the medium, her pitch has run out of energy to lift the heavy.
Chain will snap which is why snubbers and or final rode are line.
Saying of smooth sailing. Smoothing out the hammer hits to enable strength of chain to remain strong and drag the crown.
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