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Old 06-07-2024, 16:01   #1
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Twisted double braid

I have five lines on my boat (two halyards, three sheets) which are double-braid and have a 2:1 purchase via a block, and tensioned via a winch.

They all suffer from a build up of twist, and eventually the resulting friction from the block swivelling means I have to unfasten and rerun them.

Any tricks on ways to prevent or minimise the twist?

And what causes the twist in the first place? Is it the winch initial wraps? Or the rubbing against the winch skirt turning the line as it is tensioned?

It's more important than you might think, as that twist really builds up on a long passage, and I'd rather not be rerunning lines at sea.
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Old 06-07-2024, 16:50   #2
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Re: Twisted double braid

Quote:
Originally Posted by AndyOz View Post
I have five lines on my boat (two halyards, three sheets) which are double-braid and have a 2:1 purchase via a block, and tensioned via a winch.

They all suffer from a build up of twist, and eventually the resulting friction from the block swivelling means I have to unfasten and rerun them.

Any tricks on ways to prevent or minimise the twist?

And what causes the twist in the first place? Is it the winch initial wraps? Or the rubbing against the winch skirt turning the line as it is tensioned?

It's more important than you might think, as that twist really builds up on a long passage, and I'd rather not be rerunning lines at sea.

Yup, pretty annoying. There can be many causes, and combinations of causes.
  1. Coiling tails. It is really easy to add twist, even if you mindfully try not to, and every time the line is eased, some of that twist is sucked into the tackle. Either figure eight coil (does not need to be pretty, just no induced twist), or reverse every other turn (too much work for anything but heavy cables and hoses, which don't figure eight coil well), or flake into a bag. A plain store coil is deadly.
  2. Yes, winch skirts can be a factor. Also turning blocks. But not usually the whole cause.
  3. Swivel blocks. Replace every block that does not 100%, absolutely need to swivel with a fixed block. Also, most swivel blocks can be locked. If all you need is a little motion, add a shackle. By fixing the blocks the twist is forced back out of the tackle when it is pulled in. Very, very few blocks actually need to be swivel blocks. Do they actually move through a large range of angle?
Fix 1 and 3 and see if that doesn't solve it.
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Old 06-07-2024, 18:24   #3
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Re: Twisted double braid

Ah, magic. Thanks.

Seizing wire around the swivels, this could (I repeat, could...) be the first ever 5 minute boat job.

I owe you one.

As an aside, I'm paranoid about coiling. One of my more fastidious skippers insisted that lines be flaked twice, once from the winch end to get rid of twists and tangles, then flaked from the tail end so they'd run out true. He wasn't always right, but he was about that. Or if coiled, figure-eight and a hitch that doesn't pass through the coil.
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Old 07-07-2024, 03:23   #4
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Re: Twisted double braid

Winches induce twist. Coming in tight from one side and leaving slack from the other--it's a recipe for twist. Dropping coils onto the winch, taking them off: it's all twist-inducing.
You need to overhaul your lines carefully after every use, and try to only use the winch for the last couple of feet of hoist.
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Old 07-07-2024, 09:44   #5
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Re: Twisted double braid

One thing that works for me on jib sheets (I haven't tried it on halyards yet), is to add some left-hand twist in the sheet tail to counter the right-hand twist imparted by the wraps on the winch.
I used to do a lot of short tacking up the channel (before I moved), so I had lots of practice to get it right.
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Old 07-07-2024, 09:57   #6
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Re: Twisted double braid

If you coil from the winch end out, and do it properly, the twists should be minimal. If you are getting twists, look at the lead angle to the winch; it may be too low with too much friction on the skirt. Proper no-twist coiling is vital, something every climber and sailor must master. It does not need to be neat, just twist-free.



I've never done anything special to work twists out, unless ...


  • The PO coiled wrong. He did the internal reefing lines up right nice.
  • There were swivel blocks where they were not needed. Main sheet tackles and davit tackles are common offenders. In fact, I really can't think of a single place where I "need" a swivel block, other than the spinnaker crane and tack blocks. The rest simply require a little planning.
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Old 08-07-2024, 03:13   #7
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Re: Twisted double braid

This:

Quote:
Originally Posted by Benz View Post
Winches induce twist. Coming in tight from one side and leaving slack from the other--it's a recipe for twist. Dropping coils onto the winch, taking them off: it's all twist-inducing.
You need to overhaul your lines carefully after every use, and try to only use the winch for the last couple of feet of hoist.
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Old 08-07-2024, 04:58   #8
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Re: Twisted double braid

Yes, loading turns on a winch adds twist ... and then when you take them off the same number of turns are reversed. At least that has been my experience. I few weeks ago I tacked 20 times in row for a video project. I never overhauled the lines. No twist. No time, since the tacks were barely 10 seconds apart.


Coiling is a different matter. You have to coil without twist. Every time. After climbing for 40 years, I don't know another way.
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Old 08-07-2024, 14:01   #9
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Re: Twisted double braid

Yes, but when you are tacking, you aren't winching in 90+ feet of line. Which is what I would be doing if I used the winch all the way. So I don't because of the twist.
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Old 09-07-2024, 08:57   #10
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Re: Twisted double braid

I started a thread on this issue a couple of years ago and found the discussion very useful:

https://www.cruisersforum.com/forums...ng-271236.html

I had previously not considered how much twist in induced if the entry angle of the line to the winch is high so I now make an extra effort to pull in lines by hand as much as I can before resorting to the winch.

I usually take extreme care with lines to avoid inducing twists using all the methods suggested, but on longer passages when winds are constantly fluctuating and we need to frequently change between the yankee and staysail, less care is taken particularly when hit by thunderstorms and I am getting tired (we sail two up so we essentially single hand).

This morning after a 240nm passage I ran through my usual routine of carefully untwisting every line used (6 headsail sheets, 2 furling lines, main halyard and main sheet).
Most had not twisted enough to induce hockles, but this was the headsail furling line by the time I had reach the rear of the boat . We had unfurled and furled it a couple of dozen times this passage:
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Old 09-07-2024, 10:42   #11
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Re: Twisted double braid

Quote:
Originally Posted by Seaworthy Lass View Post

I had previously not considered how much twist in induced if the entry angle of the line to the winch is high so I now make an extra effort to pull in lines by hand as much as I can before resorting to the winch.

:
I think that is the crux of it. I can see the line continuously rotate in front of the winch as I crank.
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Old 09-07-2024, 11:48   #12
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Re: Twisted double braid

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I think that is the crux of it. I can see the line continuously rotate in front of the winch as I crank.
Yes, me too on some of our winches. I had not realised this until being alerted to it on the other thread.

During construction of the boat we spent some time working out exactly how much our forward winches need to be raised to give the perfect entry angle (Anderson specify 3-8) from the 2 banks of clutches. We would have had constant riding turns had we not done this, as the winches would have been too low. The other winches are positioned directly on the combing and the lines enter them from below (near the toe rail) so I need to be extra careful with our headsail sheets and headsail furlers.

The issue is not just hockling. Line strength will be dramatically reduced (halved?) if the line is twisted. Even relatively slight twisting will result in only half the strands in braided line taking full load.
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Old 09-07-2024, 16:23   #13
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Re: Twisted double braid

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Originally Posted by ggray View Post
I think that is the crux of it. I can see the line continuously rotate in front of the winch as I crank.

Yes, winching with an excessively high entry angle will do that. If you winch a halyard most of the way, that could be a lot of twist. If you need to winch the whole way, either the friction is too high or you need to considered reducing the entry angle. 5 degrees below the angle of the drum is enough. Just a TINY bit below level. For sheet winches a little more angle helps avoid overrides when you rush things. But increased angle reduces winch efficiency and causes twists.



In that case, yes, you will need to work out the twist every time. Easy enough to do.
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Old 09-07-2024, 16:50   #14
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Re: Twisted double braid

Trailing the lines behind the boat while underway will remove the twist caused by all of the above.

Self tailing winches are another contributor to twist.
More turns on the drum = more twist.
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Old 09-07-2024, 18:27   #15
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Re: Twisted double braid

I found that doing a "proper" figure-8 flake every time I put a line to bed really avoided twist problems. By "proper" I mean holding the line with my thumb on top, adding some comfortable pressure on the line as I pull it back from the f-8 coil. This runs any twist towards the tail. If I had a lot of twist, I occasionally had to shake the tail out and continue. Religiously doing this worked fine for me.

Also, I pulled and washed all my running rigging annually which helped keep the lines nice and supple, which I assumed helped in the long run.

I never saw a need to move to more drastic measures.
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