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Old 11-27-2014, 10:21 AM   #5
Delfin
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Join Date: Jan 2010
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Quote:
Originally Posted by angus99 View Post
Pretty good chance one of these will be under the tree this year.



They're offered in 3 rope sizes (5/8, 3/4 and 1 inch) and I need to specify one to Santa. My Defever 44 is about 44,000 lbs. I can't imagine why I'd use anything smaller than the 1 inch bridle even though Mantus says the 3/4" is good enough for a 40-50 ft vessel. Seems like I'd want the largest I can get for strong wind surge. For "normal" anchoring, it seems I'd still get the benefits of moderate shock load protection with the 1 inch; I'd just be dealing with a larger than necessary bridle. I certainly don't want to buy 2 for different conditions unless I'm missing something.
There are two purposes for a snubber. The first is dampening chain noise and the second is reducing strain on the whole system in a serious blow by inducing stretch. You can get the first with any size line, but the second is a function of the windage and mass of the boat. Your vessel would probably do fine with a 1/2" line.

Delfin weighs 65 tons, and our solution is probably overkill, but seems to make sense to me.

We used a 5/8" 3 strand dacron for a snub line for 5 years, but a couple of years ago I built a line that starts with 3/8" Amsteel to secure the line to the strong point, attached to 3/4" octoplait that has a breaking strength equal to the 1/2" chain, coupled to an Ultra rubber snubber. The idea is that the rubber snubber gives the kind of stretch you would get from 1/2" 3 strand for normal loads, but once it really starts blowing, the 20% stretch before breaking of the 3/4" octoplait kicks in. The bight of chain that you would lay out over the snub line would be equal to that stretch before breaking. Since our rig is around 25' long, that is around 6'. At that point of stretch you are relying on the chain.

Attaching the snub line to the chain with a hook from any manufacturer doesn't make a lot of sense to me since they will fail long before the snub line will. I prefer to use a soft shackle made of Amsteel or Plasma which is stronger than the chain.
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