Rope on rope chafe

[ScuzzMonkey]

Searched the forum, and the Webz in general about this, but couldn't come up with any satisfactory discussion of the topic.

The gist of what I am wondering is, will two braided nylon lines, one looped through the eye of the other, chafe more or less than if they were joined by a metal shackle?

My situation is this: I have a pendant coming off a mooring ball with the usual eye-splice in the end. I have two other lines with eyes in either end which I use as a bridle, which I have typically joined to the pendant with a large bow shackle, an arrangement which has generally been fine and has not resulted in any visible chafe on any of the eyes.

However, rather than messing around with the shackle, I'm wondering if I could just double the bridle lines through the eye of the pendant. But I don't know if that's going to result in more chafe potential or not.

Failing that, I can just leave the shackle on and double the bridle lines through it and back to the boat, which will also keep me from having to shackle/unshackle everything when arriving/departing as I do now.

But I'm not really sure which arrangement would be best. What do you folks think?

[GregSteimel]

Not sure I understand. How is the bridle hooked to the pennant? Through, somehow?

Mine is arranged thus: the biggest shackle I can find on the ball and two pennants forming a bridle with each to opposing deck cleats.

And the 4 inch shackle isn't big enough: the two eye splices are forced, by the circumference of the shackle, at an angle to each other, rather than being in parallel.

A bigger hackle would be better but maybe if I had a bigger swivel and 2 shackles...

[ScuzzMonkey]

Originally Posted by GregSteimel

Not sure I understand. How is the bridle hooked to the pennant? Through, somehow?

That's the idea, yes, to just loop the bridle lines through the pendant eye. What I'm wondering about is the chafe potential in those loops.

Currently, they're joined, eye-to-eye-to-eye, with a shackle, pretty similar to your description. I think the big difference is I have a single pendant line, to which the bridle is rigged, rather than two pendants to form the bridle.

[GregSteimel]

I have 2 bridles so one backs up the other. They get twisted up but never fatally.

If you mean you have a single line running from the boat through the eye and back to the boat, I'd expect lots of chafe. My method has worked for years and, other than the problem I mentioned, hasn't shown wear yet. My pennants are probably both over-sized, which causes the weird angle at the shackle.

[ScuzzMonkey]

No; it would be two lines, both doubled as you describe, thus forming the bridle and backing one another up, just as you say.

Really, I just included the mechanics to be complete, and I feel like we're getting hung up on some of the less-relevant points. The basic question is, does anyone have any information about rope-on-rope chafe, particularly versus rope-on-metal chafe?

[Stumble]

Yes rope-rope will chaff, and depending on the line it can be pretty major. The other issue is that an eye splice thru another eye doesn't have a large enough radius bend for the line to bend around, which will dramatically reduce the strength of the line. When combined with chaff right at the load point it is a recipe for a quick failure in the line.

For heavily loaded line like this it is better practice to eye splice a thimble on the ends, then use a large shackle to attach them to the fixed point.

[ScuzzMonkey]

Well, the pendant is a 1" hawser in this case, so the eye actually has a greater radius than many thimbles in these setups, but point taken! It sounds like I should leave the shackle in the mix and avoid the rope-rope contact.

Thanks!

[Wotname]

FWIW, if the two ropes are different diameters (but same construction), the small one chafes the big one more than vice versa; sort of counter intuitive.

[zeehag]

i used lines spliced with thimbles and then affixed to shackle and pendant with each of my 2 lines on a different link in chain. the pendant made my Y single leg of the bridle. worked great with minimal chafe

[sabray]

New England ropes shows there cyclone pendent with two eye splices looped through one another.
I use a similar set up with my mooring. . Not sure why you are unshackling your pendent. I put mine on and it stays for the season.
http://www.neropes.com/Datasheets/MAR_CYCLONE.pdf

[zeehag]

i used 2 separate lines shackled to pendant in a bridle fashion. our pendants were 6 ft lengths of 1 in chain pendant and i placed each line on a different chain link for security and safety and was comfy all season. i brought 2 mooring lines with me, and have 2 left on my ericson. they were provided by mooring company fro a fee and mine were 1 inch and 1 1/4 inch lines.
this is the bay wherein the allegedly notorious china chain incident occurred 1999, easter sun am 0200 when 1 inch chain link split open in over 65 kt winds and appropriate heavy chop on sd bay. .....i took no chances. others broke loose but mine were fine.

[estarzinger]

Originally Posted by sabray

New England ropes shows there cyclone pendent with two eye splices looped through one another.
I use a similar set up with my mooring. . Not sure why you are unshackling your pendent. I put mine on and it stays for the season.
http://www.neropes.com/Datasheets/MAR_CYCLONE.pdf

This is the way to make a rope to rope join . . . no loss of strength and no chafe, and can be easily disassembled.

Here is a picture of my bridle joined this way . . . .

[sabray]

[QUOTE="estarzinger;1400034"] This is the way to make a rope to rope join . . . no loss of strength and no chafe, and can be easily disassembled. Here is a picture of my bridle joined this way . . . . [/QUOTE
Right just like it shows in the New England ropes link I posted. That's how I did my pendent using dyneema.

[ScuzzMonkey]

Not sure why you are unshackling your pendent. I put mine on and it stays for the season.

Not our permanent mooring; a place we stay for a few weeks at a time, from time to time. So the gear travels with us.

Thanks for all the feedback. Learn something new here all the time.

Thanks folks!

[Stumble]

Originally Posted by sabray

New England ropes shows there cyclone pendent with two eye splices looped through one another.
I use a similar set up with my mooring. . Not sure why you are unshackling your pendent. I put mine on and it stays for the season.
http://www.neropes.com/Datasheets/MAR_CYCLONE.pdf

The cyclone is bad practice overcome with massive redundancy. Figure the three strand has a breaking strength of 7,500lbs and the cyclone is a minimum of 35,000lbs. It may be bad practice, but is so massively strong it really doesn't matter.