Anchor Bridle vs Single Line Snubber

[Euro Cruiser]

Tough, tough conditions. Thanks for that, Gord...tho' it gives me the willies.

I see two initial failures, different from one another, after which the fat's in the fire as there's no telling a successful veering of line would have improved anything. It's splice to the chain could have failed, the line could have been lost due to chafe at the hawse pipe (very tough to add adequate chafe-guard to a line under that strain) or the line itself may have failed, just as happened with Snubber #1.

However, there's a good lesson for those favoring a chain hook with the loss of Snubber #2. I've seen a lot of chain hooks that are roughly cast which leads me to worry about two things: first, the quality of the casting (you used to be able to find chain grabbers that were drop forged; I haven't seen any of these in some time) and second, the mold line of the hook's eye can be quite sharp. And one is reluctant to smooth it out because the galvanizing goes away. In some cases this mold line is like a rough knife blade.

Jack

[FSMike]

Originally Posted by jkleins

But if you don't set the chain break won't the boat just float free if the snubber fails?
I have always set the chain brake and then put a snubber on if desired so the chain takes the strain if the rope fails. How that will damage the windlass.

Jim

I think you will find that most windlass manufacturers say not to rely on the windlass for securing your rode while at anchor. That's when you should be using your samson post. If your chain rode is secured to a samson post or appropriate cleat it won't matter if your snubber fails.

[forsailbyowner]

I guess my daily use snubber is a combination of both. I have two 3/4" lines spliced to form V from bow cleats that step down to 1/2" . The 1/2" is sewn into a canvas sock with multiple shock cord lengths. After the 10 or so shock cord lines are stretched the elasticity of the nylon takes over. Termination to chain via snap shackle. For extreme conditions I use a three line snubber all attached to a 3/4" swivel that would attach to a multiple anchor mooring setup with possible lines run to shore or whatever is available.

[Sandero]

Jack,

I use a stainless steel reefing hook for my chain hook. It's very positive and easy to engage... I am not concerned about mixing stainless with the galvanized chain.

[thinwater]

The only time I ever pulled an anchor that was the cause. I had anchored a small cat by one bow only, with the main still up (lunch stop). Sailed it right out.

The sailing at anchor probably atleast doubled the forces involved and thus caused the failures. I have seen this modeled and have seen it in practice. That behavior MUST be stopped in strong conditions. A hamerlock mooring might have been wise and would not have prevented a quick get-away. There are other solutions, too, but leeway resistance forward is the key.

[jkleins]

Originally Posted by FSMike

I think you will find that most windlass manufacturers say not to rely on the windlass for securing your rode while at anchor. That's when you should be using your samson post. If your chain rode is secured to a samson post or appropriate cleat it won't matter if your snubber fails.

I was thinking about the boats without a samson post. I have never seen that done with chain. How would you secure a chain to a samson post or a cleat?
I think we are talking about two different things. I am talking about the in-line chain stoppers (which I call a brake) that you set over the chain and then release the clutch of the windlass (which is what I think you are calling the brake) taking the strain off the windlass mechanism. I have had two windlasses and both had inline stoppers that didn't require the chain be removed from the windlass. The Maxwell suggests the chain stop be in between the anchor and the windlass but the older Ideal windlass actually has the stop built into the chain pipe so the windlass does take a lot of the strain although not on the clutch just the post.
You were probably referring to just leaving the chain held by the clutch of the windlass and I agree with that sentiment but I think taking the chain off the windlass seems like a lot of trouble and is not something I would ever consider doing. Is that a common thing that people do?

Jim

[FSMike]

Jim -
You attach a chain to a samson post or cleat in the same manner you do a rope rode. I don't usually find it necessary to finish off the chain by turning it under on the last loop however.
We remove the rode from our windlass and secure it on a large cleat installed for that purpose every time we anchor. Of course by that point we are usually into the rope section of our anchor rode.

[osirissail]

Double "Indeed" - Chain Stoppers or sometimes called chocks should be installed downstream from the Windlass. Using the gypsy on the windlass to act as a Chain Stopper can be a very expensive mistake. Besides loosing or nearly loosing the boat, just plain normal anchoring without a chain stopper can result in severe shock loads on the windlass should a large wake or wave snap your anchor chain rode taught. Inside the windlass are gears and a tooth can be sheared off - or - in my case there is a shear pin on the through-deck shaft between the motor and the gypsy. That will shear letting the chain free-wheel out of the well.
- - Chain stops should be massive and thick enough to easily handle the maximum rating of chain and be very strongly attached to the bow with backing plates, bolts, etc. to ensure that it can absorb the full load (chain rating). Then there is no load at all on the windlass or gypsy until you start to haul in the anchor.
- - Here are some examples:

[Sandero]

My maxwell has a cam which you can use to lock the gypsy... but you should be using something to add stretch and absorb shock in any case so the chain stoppers only work without a snubber. Why bother with them? And futher if you use one without a bridal or snubber you place all the anchor loads on the two or three small bolts of the chain stopper (see previous post image). How smart is that?

[thinwater]

Originally Posted by defjef

My maxwell has a cam which you can use to lock the gypsy... but you should be using something to add stretch and absorb shock in any case so the chain stoppers only work without a snubber. Why bother with them? And futher if you use one without a bridal or snubber you place all the anchor loads on the two or three small bolts of the chain stopper (see previous post image). How smart is that?

Why bother is at the start of the thread.

Small bolts? Mine is held by two 3/8-inch bolts with a huge backing plate. That would make it stronger than the 1/4-inch HT chain. 5/16-inch would have done fine.

The problem with snubbers, we are learning on this thread, is that they can be difficult to protect from chafe. Catamarans always use snubbers, in the form of bridles, but because the angle of pull does not vary and because the designers provided for the use of bridles, they are easy to protect from chafe.

[CharlieJ]

One point that has not been made is that the use of standard chain hooks puts enormous cross axis stress on the chain link that the chain hook is attached to. In following an expert's recommendation, I found a forged steely "Devil's Claw" with a pocket that engages the chain link and keeps the stress on the chain along the chains' axis. The single 3/4" twist, nylon snubber had a thimble spliced in the end and the chain claw was attached to the snubber with a high strength shackle.

Claw.doc Views: 193 Size: 50.5 KB ">Devil's-IRJDSUNE9932123321222xxeww-Claw.doc

With this arrangement I have anchored my 50,000 pound, moderate windage trawler well over a thousand times in varying conditions, not including anything greater than a tropical storm, with a with absolutely no problems. Every time the anchor is weighed, the snubber is disengaged and inspected for chafe and overall condition.

[BessLB]

Thanks for all the information! I'm learning a ton from you guys. I'm not sure I understand the concept of tying off my chain from the windlass to the samson post though. We have an electric windlass. Do I attach the snubber or bridle, let out extra chain to hold it taught then pull some chain back past the windlass to secure to the post, with a cleat hitch?

I like the idea of one or two line snubber(s) through the rollers much better than the bridle below the bowsprit. That just doesn't sound easy to work with.

Thanks again All!! And Happy Holidays!
Bess

[GordMay]

This picture doesn’t show the chain stopper, which would be located between (or at) the anchor roller and the winch, but (otherwise) illustrates the principle well.

[thinwater]

Originally Posted by BessLB

Thanks for all the information! I'm learning a ton from you guys. I'm not sure I understand the concept of tying off my chain from the windlass to the samson post though. We have an electric windlass. Do I attach the snubber or bridle, let out extra chain to hold it taught then pull some chain back past the windlass to secure to the post, with a cleat hitch?

I like the idea of one or two line snubber(s) through the rollers much better than the bridle below the bowsprit. That just doesn't sound easy to work with.

Thanks again All!! And Happy Holidays!
Bess

Which is where the thread started. IF you make the snubber over-size there is no stretch and no point. You can cover it with a tubular webbing chafe guard (Sail Delmarva: Anchor and Bow Details).

[osirissail]

The use of a "snubber" on your anchor rode is a separate subject from "chain stoppers". The use of the Snubber is to allow some stretch to occur - like a shock absorber - when a load is quickly applied to your anchoring system. For instance, a work boat, or other rude boater generates a large wake that impacts your boat and tries to shove it opposite from your anchoring direction. This sudden increased load on your anchor can cause it to dislodge from the bottom and set you adrift. The snubber converts that sudden extra load to a load over a longer period of time so your anchor does not get "ripped" out of the sea bottom.
- - Anything that has good stretch works. Most common systems I have seen are 3-strand nylon line or a bridle from nylon line run from deck cleats/samson posts over the bow and then using an attachment system to grab the chain. The nylon three strand will stretch up to 50% of its length before failing so it makes a good shock absorber. The rubber snubbers also do the same job but are (maybe) more expensive.
- - You use a bridle (two lines from port and starboard cleats) or a single line depending upon the configuration of your bow and whether the boat has a tendency to "dance the anchor."
- - Chain Stoppers are heavy duty devices with very strong through bolts designed to transfer all the shock loads and other heavy storm wind loads to the hull of the boat versus to a windlass system. Windlass are not cheap and contain gears and shafts that can be bent by shock loads. Windlass were invented to raise your heavy anchor for you and save your back and hands the strain of hauling in heavy chain and an anchor. They are not designed as a Samson Post or deck cleat. Under most normal conditions they will function thusly just fine. But should a heavy shock load occur that exceeds the ability of the "snubber system" to absorb - you are going to make the Windlass manufacturer very happy by having to purchase expensive repair parts or a new Windlass after you rip the windlass out of the deck, bend the shafts, or strip the gears. Having a properly mounted chain stopper on deck will make the Windlass manufacturer very sad as you will not need to buy those repair parts.