Anchor Rode Bridle and Snubber

[Benny]

I have seen several posts throughout the site on using bridles and snubbers for anchoring. I have a heavy monohull.

I have a rode of 70 feet of HT chain and 200 feet of 3 strand top quality nylon rode. I have a 3 foot long bowsprit/platform with a roller about halfway along it through which the anchor stem passes to rest ontop of the platform and is secured from falling back by a pin on a plate. I have an electric windlass about 3 feet aft of the bow and I have a heavy stainless mooring bit about halfway between the windlass and the bow through bolted with a 1/4 inch aluminum backing plate which spans the entire fordeck underneath in the chainlocker. The bollts and hawse for the windlass goes through this plate as well as the outboard cleats. I installed the windlass, mooring bit and backing plate last year. There are raised bulwarks with a hawse on each side near the bow for mooring lines. The aforementioned cleats are near these.

Here is my question: there has been posts that advize to not use a bow roller to achor from as it can pull out or break or cause your bowsprit damage etc. so I want to use a bridle system led through the hawses on each side of the bow. For shallow mooring, I have a heavy snubber plate which drops over the chain and I can shackle a line to each side of it and lead them through the hawse to the mooring bit. Do these work - I would think it could turn and drop off the chain or is there some securing method fior the snubber plate to the chain that is quick and simple?

For deeper mooring, I will need to attach the bridle to the nylon rode and have seen suggestions on using a rolling hitch - what is the best procedure to do this?

Because of a large and wide bowsprit platform, it will be a little more difficult to get at the bridle and hardware involved secured to the rode in these methods . Does anyone have a good system?

I have a fair idea of how I would do it but there is alot of mooring experience in this forum and tried and true methods are best.

Thanks for the help, Randy

[GordMay]

I’ve always used the Triple Sliding Hitch (Prusik) for attaching rope to rope (snubber to rode):
The Prusik Knot or Triple Sliding Hitch

See also, the previous discussion “ Rolling Hitch nylon rode snubber?”:
http://www.cruisersforum.com/forums/...bber-2380.html

See also the the Klemheist or the Bachmann at Annimated Knots by Grog:
Animated Knots by Grog

[Benny]

Thanks Gord - I have a 5/8 nylon rode and I'm concerned about using a 3/8 snubber line for strength - my displacement is 22,000 lbs.

Do you think that a doubled up snubber line would still work properly with the Prusik knot so that I can lead one line to the port hawse and the other to strbrd to get the bridle I want?

Is there a chafe problem using the Prusik on chain instead of a chain hook or my expensive stainless chain snubber plate (which I would return to the store)?

Does the knot along with turning the rode sideways under tension weaken the rode?

Thanks for your help and anyone else that may have ideas on this setup.

[Rick]

For decades now I've been using a Prusic hitch to attach my snubbers to either the chain or nylon part of the rode. The hitch works just fine on the chain and after you begin using it you will wonder just why anyone uses chain hooks or other devices to attach to the chain.

If you slack off of the snubber you can use a bow hook to "hit" the crossover loop of the Prussic and loosen it sufficiently to slide further out (more difficult to do on chain, though). The beauty of this is that you can attach several snubbers to the chain or rode and set each one to take up load should the first set ones break under heavy waves/loads. My snubbers always broke wherever they chafed exiting the boat (farlead or whatever). After making up double-brade dacron "interface" lines from the cleating point to outboard of any potential chaffing the nylon snubber then attaches to the dacron. The Dacron will not stretch sufficiently (for your boat use 9/16 to 5/8" dacron) to cause significant chafe (assuming that you have carefully dressed any fairleads and cleats, etc.).

For a bridle you can make a single loop from say a port cleat outboard and across the bow to the stbd cleat (the whole thing can be Dacron) and use a Prusic hitch from the center of the loop to the rode. You can middle a length of snubber and attach it at the middling point to the bridle center and lead both ends to the rode if you want. It will work fine.

With practice you will be able to tie the Prusic one-handed and remove it similarly. Yes. at times there will be some wrapping of the snubber on the rode yet that should not be a problem as it will not be excessive. I use the windlass to bring the rode/chain and Prusic attachment over the bow roller almost to the windlass, stop and more conveniently remove the hitch, unwind the snubber from the rode, get it out of the way and continue retreiving the anchor. Deploying is the same in that you can lead your snubber over the bow roller and more conveniently attach it to the rode near the windlass without having to lean overboard to do it. Then release the rode until the snubber takes up the load with sufficient slack in the rode so that when the boat sails at anchor the snubber is always taking the load.

I think that 25 ft of 3/8" snubber deployed will work for your boat in relatively light conditions yet you may have to go to 1/2" with a heavy surge.

[Benny]

Rick - thanks very much for a complete and detailed explanation and a great idea for attaching and unattaching the snubber by using the windlass - I don't know why I didn't think that one out - duh.

Regards, Randy

[Tramp]

The Klemheist knot (or Machard knot):
http://en.wikipedia.org/wiki/Klemheist_knot
is preferred by alpinists over the Prusik knot (or hitch) because it never locks. Same thing here maybe.

Also, I have found it very efficient on chain (wrapped 4 turns) and large mooring lines (wrapped 5-6 turns).

[Badsanta]

Thanks, I will try it

[Whimsical]

The Klemheist knot and the Prusic hitch both require the bridal be attached to the rode or chain first then attach the bridal to the cleats. In other words they wont work if the bridal is permanantly attached as it is on some, mine included, cats.
The only knot I know of that is similar uses a carabiner to function, a Bachmann knot.
Any other alternatives for this situation.

Mike

[Therapy]

Originally Posted by Whimsical

The Klemheist knot and the Prusic hitch both require the bridal be attached to the rode or chain first then attach the bridal to the cleats. In other words they wont work if the bridal is permanantly attached as it is on some, mine included, cats.
The only knot I know of that is similar uses a carabiner to function, a Bachmann knot.
Any other alternatives for this situation.

Mike

I am trying to figure this out.
If you attach the bridle to the chain or rode first then what is the prusic knot for? I just don't understand.

And probably never will without a picture.

[speedoo]

What do you all think of this arrangement:

http://www.cruisersforum.com/gallery...p?i=1122&c=500

Pretty nifty, IMO.

[GordMay]

Originally Posted by Whimsical

The Klemheist knot and the Prusic hitch both require the bridal be attached to the rode or chain first then attach the bridal to the cleats. In other words they wont work if the bridal is permanantly attached as it is on some, mine included, cats.
The only knot I know of that is similar uses a carabiner to function, a Bachmann knot.
Mike

Although that may seem so, as illustrated on “Animated Knots” and other tutorials, the Prusic Hitch can be tied with a single running end, with the other end secured (which is how I first learned as a construction rigger).

A picture ➥ http://www.bosunsupplies.com/snubber.cfm

Pic shows a hook in lieu of the hitches discussed.

[Meridian]

Benny...we've been cruising the South Pacific for 2 years now, and have used the same snubber-plate that you describe. We anchor every night when not on passage, and have had several 30, 40 and even a 50-knot night,
Four things will help you set up this plate to be bullet-proof:
1) drop it onto the chain from ABOVE. The slot in the plate should face down.
2) after deploying your chain and snubber, drop a few more meters of chain...
This creates a weighted loop of chain that helps hold the plate in position.
3) run the bridle lines over the pulpit. This keeps them parallel, and essentially eliminates any lateral pull to one side or the other on the plate (if let to port and starboard cleats, one or the other leg of the bridle will be taking the full load as the boat swings through the wind. This imposes side-loads on the plate, which can stretch it open. Been there, done that).
4) chafe protection is critical. At the roller (or chocks if you go that way), and at any/ all areas where the bridle could touch anything. Can't emphasize enough. Fire hose works great (split it lengthwise).

And, rigging a back-up snubber is cheap insurance.

Hope it helps...we're currently riding easy in 27 knots in Fiji, 3 days now. No problems with this set-up.

John

[Meridian]

Sorry, missed the part where you said you had 70' of chain, then rode.
Regardless, if you're on chain only, the snubber-plate tips work well.


BTW, I've had carabiners, even the big, beefy Kong ones, fail under moderate conditions.
I'd use one hesitantly as a light-condition primary, and never as a back-up.
John

[thinwater]

Originally Posted by Meridian

Benny...we've been cruising the South Pacific for 2 years now, and have used the same snubber-plate that you describe. We anchor every night when not on passage, and have had several 30, 40 and even a 50-knot night,
Four things will help you set up this plate to be bullet-proof:
1) drop it onto the chain from ABOVE. The slot in the plate should face down.
2) after deploying your chain and snubber, drop a few more meters of chain...
This creates a weighted loop of chain that helps hold the plate in position.
3) run the bridle lines over the pulpit. This keeps them parallel, and essentially eliminates any lateral pull to one side or the other on the plate (if let to port and starboard cleats, one or the other leg of the bridle will be taking the full load as the boat swings through the wind. This imposes side-loads on the plate, which can stretch it open. Been there, done that).
4) chafe protection is critical. At the roller (or chocks if you go that way), and at any/ all areas where the bridle could touch anything. Can't emphasize enough. Fire hose works great (split it lengthwise).

And, rigging a back-up snubber is cheap insurance.

Hope it helps...we're currently riding easy in 27 knots in Fiji, 3 days now. No problems with this set-up.

John

A latch on the plate also makes it very secure, particularly in shallow areas where it will be bouncing on the bottom. See my blog entry:

Sail Delmarva: The Ultimate Chain Hook for Catmarans...

[barnakiel]

Bow roller OK if built like a tank. But we use the snubber anyway.

b.