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Old 29-06-2009, 05:12   #16
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Originally Posted by mesquaukee View Post
You can keep a monohull from swinging at anchor by using a single line snubber.
Clip your chain hook onto your anchor chain and attach the end of the line to the stern. Let out a bit of chain till you are about 30 deg. to the wind. You will stay on one tack...
Think of it as an anchor rode Spring Line.
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Old 29-06-2009, 05:54   #17
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Depending on the angle of the current, it may not be advisable to run the snubber off the stern. This may put the angle too severe at the bow and the chain can ride off the roller or abrate the sides of the roller. In that case you would want two subbers, one for the bow and a second to pull the stern to align with current. The bow snubber is needed to reduced the shock loading and is necessary.

For a snubber I use a 1" braid on brain nylon line woven through a heavy rubber mooring compensator which runs over the bow roller and uses the windlass as a "fair lead" to a bow cleat which is well astern of the windlass. This does not load up the windlass.

The compensator not only increases the shock absorption, but it act like a handy "tell tale" to indicate that the anchor is set and not dragging. In gusts you can see the compensator stretch a bit and that means that the anchor is well set. If it's dragging it won't stretch.

When anchoring, likewise, then the anchor sets, the mooring compenasator will stretch a bit and you know that the anchor is now set and the chain is straight, and properly deplayed and not sitting in a pile on the top of the anchor.

If it's blowing hard, you should see the compensator stretch to the gusts and if it isn't, you are likely dragging with little tension on the chain rode.

When the snubber is deployed the chain aft of it is lifted over top the snubber line (it has no tension). The subber is not prone to chafe from bob stays etc. even if the bow shears a bit.

Most mooring and achor failors are due to chafe.
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Old 30-06-2009, 01:23   #18
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Quote:
Originally Posted by mesquaukee View Post
A note on galvanized chain hooks as pictured in MarkJ post. It might not look pretty but it will not fail. The chain will stretch (the links will elongate) before this hook will break.
If you are using high test chain you may want to use a grade 8 hook (sane grade of metal as your chain)
The stainless versions are fine as well and you are right in saying most chains will change shape before the hook breaks. We use the same hooks in our little test bed.

By the way the hook pictured is a G70 (used extensively in the trucking game) and High Test chain is only a G40.

What sort of compensator do you run in your snubber defjef? One of the longish black ones (sometimes referred to as 'a ladies friend', no idea why ) or another sort?
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Old 30-06-2009, 02:00   #19
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rail mounted bag

Hi

looking at the attached thumbnails I am curious to know what is that cloth elongated brown narrow bag mounted on the lifeline and pulpit port side for ??
thanks for the info


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I have a locking pawl on my windlass but then I have a chain-hook snubber with line to a reinforced cleat to take the load off the windlass, and then I have a chain-hook and nylon bridal which takes the load off the snubber and springs the jerk on the chain. Yes, I sometimes wear a belt and suspenders too.

I like the bridal not only because it springs the chain, but it is easier to warp the boat around into the waves when they are contrary to the direction the boat is setting. Also, when the boat is pitching badly into the wind and waves I ease the chain so the bridal is prevented from going under the boat and move the bridal ends well aft, sometimes as far aft as the cockpit winches to a neutral position to prevent any yanking on the anchor caused by the pitching.

I'm kind of particular about anchoring and have 5 anchors on my boat. In Pict 1 below is my Windlass w/chain to my FX-37 mud anchor with a snubber on the chain, and picture 2 shows one side of a bridal waiting to be attached. I use forged hooks for my chain grabbers and I always Mouse the hooks.

Good Luck

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Old 30-06-2009, 06:37   #20
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I am curious to know what is that cloth elongated brown narrow bag mounted on the lifeline and pulpit port side for ??
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Old 30-06-2009, 06:46   #21
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I use a rubber one about 1 1/2" (guess) in diameter and 20" long (guess)

here's a pic:
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Old 30-06-2009, 08:36   #22
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I've got the same "problem."

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Originally Posted by MarkJ View Post
Our snubber rope is soooo old that I'm thinking of replacing it... but if its not broke.........
I use a simple chain hook spliced to undersized three-strand nylon. Last time I built one I managed to whip out the most perfect eye splice of my life. When I held it up for the wife to admire, she pointed out that I'd forgotten to splice in the thimble.

So I figured I'd use it anyway, even though it would probably chafe through in a month. But that snubber has been going for years now, and appears to have a few more years left in it. Indeed, I may have to regalvanize the hook before the nylon wears out.
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Old 30-06-2009, 17:17   #23
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A Dynamic not a Static I hope. A Static is only allowed to have 10% at break so piles less than a yachting rope. Dynamic do and are indeed designed to stretch more than Static but even then bugger all more, if at all, than some ropes used by boats. But climbing ropes lose their stretch relatively quickly compared to average boat ropes. A couple of things to keep in mind.
Is there any testing to support the assertion that the stretch does not last? I used a retired 11mm climbing rope for a rode on a 27' boat for 15 years, and it seemed just as good in the last thunderstorm (a real snorter in the last season - thought the boat was going to fly) as the first. Is there and engineering argument based in rope construction?

Climbing rope does not work in a windlass; it is designed NOT to catch on bumps on the rock. It requires a splicing method not generally known but available in the net. It has better knotting strength.

Basically a snrubber needs to stretch enough to absorb wave action. Gusts are NOT effectively absorbed, as the boat simply has a better chance to get moving and hits the chain nearly as hard, anyway. So, the correct snubber depends on the mass of the boat and the size of the waves.
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Old 30-06-2009, 18:16   #24
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Is there any testing to support the assertion that the stretch does not last? I used a retired 11mm climbing rope for a rode on a 27' boat for 15 years, and it seemed just as good in the last thunderstorm (a real snorter in the last season - thought the boat was going to fly) as the first. Is there and engineering argument based in rope construction?
Back in my day the way to tell when to retire a climbing rope was to measure it. If a stretched rope fails to return to close to its original length, it's no longer to be climbed upon.
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Old 30-06-2009, 18:35   #25
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We have a 6 ft bowsprit and since we have nice pair of bow cleats with built in fair leads I like the bridle approach. It places all the load on these two points firmly built into the boat and not hanging off the bowsprit. It does effectively reduce the angle of the rode to the boat.

If you have puny bow cleats attached only to the deck snubbing is going to matter a whole lot more. With bigger boats snubbing alone won't help enough so the place you actually attached to matters a lot as well. You don't want to rip a chunk of the boat out in a gale or squall. It's not the time you will be able to deal with it easily and it's the only time it will happen. On the nice evenings you can just sit at a pile of chain in the water and be fine. It's easy to be lazy.
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Old 30-06-2009, 20:38   #26
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Good point - I have done that too.

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Back in my day the way to tell when to retire a climbing rope was to measure it. If a stretched rope fails to return to close to its original length, it's no longer to be climbed upon.
However, that doesn't give a comparison point to other common ropes and aging. Climbing ropes are rated for their ability to absorb energy, not strength, although they are of comparable strength to other premium nylon ropes. Those ropes are not tested for energy absorption.

A good research project for someone. Of course, climbing rope construction is not generally useful for anchoring with a windlass, so I'm sure no one will have interest. Just like no climber will ever touch a premium anchor rode, though the later is considerably cheaper. Horses for courses.
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Old 30-06-2009, 20:51   #27
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Length: The snubber should be at least 3 times the highest wave that will be encountered. For example, if you can get a freak 5 foot wave in your anchorage, the snubber should be at least 15 feet long.
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Old 01-07-2009, 04:48   #28
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Length: The snubber should be at least 3 times the highest wave that will be encountered. For example, if you can get a freak 5 foot wave in your anchorage, the snubber should be at least 15 feet long.
Interesting rule of thumb.
Can you explain the underlying principle(s)?

PS: Expect I'd generally use longer snubbers than the minimum your advice would suggest.
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Old 01-07-2009, 05:26   #29
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New nylon can stretch about 40% before breaking. Allowing 30% (age and attachments), a 15 foot snubber can stretch 4.5 feet. That should be sufficient for a 5 foot wave, considering the catenary of the chain and the boat dipping before rising.
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Old 01-07-2009, 08:10   #30
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your question about the long bag.

There appears to be one on the Starboard as well. Maybe some kind of hand made storage. I would like to know as well.

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Hi

looking at the attached thumbnails I am curious to know what is that cloth elongated brown narrow bag mounted on the lifeline and pulpit port side for ??
thanks for the info
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