Rope bridle to rope rode - like a Cadillac - a report

[Chotu]

Now that I am in deep water and deep anchorages, I have gone beyond the usefulness of my 100 ft of chain.

The rest of my larger boats have always had all chain rode. they also had a simple monohull snubber.

On this boat, it’s 100 feet of chain followed by 200 feet of rope rode to keep weight down.

Little did I know that it would be so luxurious. Using the standard bridle that you would normally use with a chain and hooking it up to a nice stretchy piece of rope rode that is spliced to the chain is unbelievable smooth.

there is no more jerking and rapid movement whatsoever. The boat feels like it is stationary in the strongest thunderstorms. it has more of an up-and-down acceleration than a fore/aft tugging acceleration like it has when you are on all chain.

it’s really really comfortable.

I was a little bit nervous that my bridle attachment technique would slip because the rope rode does not have the same deep grooves a chain does for the bridle to grip onto. I’ve had some fairly good winds in storms and it's holding great.

I'm using a doubled prussik on one of the rode attachment points and my gripper knot (bitter end) on the other rode attachment points. I'm using different techniques as a test. Attached is a pic of the gripper knot. Love this knot.

Note: I give the gripper knot an extra turn around the rode and extra half hitch in the opposing direction from the last one in the diagram. Seems better. I've had it come partially loose in extremely calm conditions and the added opposing half hitch going the other way around the rode prevents that

[GordMay]

I also used the Prusik Knot / Triple Sliding Hitch
I usually used three turns, in each direction, but more turns = more security. This knot must be tied with a rope of diameter less than the main rope, as the effectiveness of the knot is reduced, the closer the two ropes are in size. The Prusik knot is symmetrical, so is effective, regardless of the direction of pull.
➥ https://www.animatedknots.com/prusik-knot

Or the Klemheist / Machard Knot
➥ https://www.animatedknots.com/klemheist-knot

[Chotu]

thanks for adding the Klemheist knot to the thread, Gord. Another interesting one.

[GordMay]

Tying a Prusik Knot on the Running End of a Line [not on a loop]
➥ https://youtu.be/o-v_gkryz-c
➥

https://www.youtube.com/watch?v=VKrJW2TeH74

[rslifkin]

Having plenty of stretch in the rode does really smooth the ride out. And deep water helps the ride too. The combination can make things very nice and comfy.

The only thing to watch for is really gusty winds (especially if they're slightly shifty). With too much stretch in that situation, the boat can end up stretching back far enough in the gusts that it slingshots forward significantly when a gust lets up. And then falls back potentially at an angle in the next gust until the rode goes tight and pulls it back around to straight.


I've also found an interesting effect with higher winds in fairly well protected anchorages. The more wind you have for a given size chop (and therefore the more anchor rode tension), the less the chop is felt on at least some boats.

[GordMay]

FWIW: As an experiment, I once tied a pair of tipple sliding hitches [Prusik], in a piece of 3/16" Ø flag halyard, about two feet apart, on a 5/8" Ø three strand anchor rode. They were hitched so that the 2 ft of small stuff created a slack loop, on ± 4 ft section of rode. I marked their position, on the rode, with a sharpie.
Thus, the small stuff took the entire anchor load.
I promptly forgot about it, for a month [or so], during which we weathered several 25 ➛ 30 knot [+?] blows.
When I finally remembered the experiment, I found that the 3/16" small stuff was still in place, creating the slack loop in the 5/8" rode, totally undamaged, just as I had left it.
It didn’t slip, stretch, or break.

[Nekton73]

I also have a rope rode/chain combo and my go to for the bridle is also the prusik. I use a triple prusik and have never had it slip either.
I've often wondered if the prusik reduces the breaking strength of the rope it is grabbing.

[Franziska]

Chotu, ever tried a loop instead of the constrictor knots?
Just looping it through itself several times around the rode and then hooking the bridle into its middle works well.

[GordMay]

Originally Posted by Nekton73

...
I've often wondered if the prusik reduces the breaking strength of the rope it is grabbing.

Perhaps, this report might answer your [interesting] question. I haven't read it, myself.

Ropes and Friction Hitches used in Tree Climbing Operations
This, 64 page, report presents the results of a research project carried out into ropes and friction hitches commonly in use in tree climbing operations in the United Kingdom.
➥ http://www.paci.com.au/downloads_pub...PBavaresco.pdf

[Chotu]

Originally Posted by Franziska

Chotu, ever tried a loop instead of the constrictor knots?
Just looping it through itself several times around the rode and then hooking the bridle into its middle works well.

Trying to understand this approach

I’m not grasping it unfortunately. Can you give more detail?

[odonnellryan]

Originally Posted by Chotu

Trying to understand this approach

I’m not grasping it unfortunately. Can you give more detail?

I imagine something like this (this is for climbing, but you can easily make one for anchoring I imagine).

I was going to suggest the same. I use this method, but with a cow hitch to my chain. Can easily just add a few loops and it's a prusik if your loop is long enough.

[Franziska]

Originally Posted by Chotu

Trying to understand this approach



I’m not grasping it unfortunately. Can you give more detail?

Essentially like this (not our bridle).
You make the loop once. Than you can easily loosen it, reposition it or reattach it.

[Nekton73]

Thanks Gord, while the report doesn't directly answer the question the results of the various pull tests alleviate any concerns. Very interesting.

As the prusik is a fast and simple hitch, and easy to manipulate, it will continue to be my go to.

[Chotu]

Originally Posted by odonnellryan

I imagine something like this (this is for climbing, but you can easily make one for anchoring I imagine).

I was going to suggest the same. I use this method, but with a cow hitch to my chain. Can easily just add a few loops and it's a prusik if your loop is long enough.

I would just call that a quadruple Prussik. I don’t know. I’m no expert on the wording of knots lol

This is exactly what I do. With one of the bridle lines. I use a double Prussik

[Chotu]

Originally Posted by Franziska

Essentially like this (not our bridle).
You make the loop once. Than you can easily loosen it, reposition it or reattach it. Attachment 278724

Hey, that’s pretty nice!

I like it.

Really simple. Do you tie a bowline to it to connect the bridle lines?