Help-I've got hockles in my sheets and need to get them out!

[joelm100]

Hi all, this is probably a mundane question but I'm not finding anything on the forums. My Hunter 380's main sheet gets twisted up between the block at the traveler and the terminus on the boom. Sometimes just a couple days of sailing will create a twisted mess necessitating releasing the sheet from the boom and untwisting; obviously this is a hassle if sailing.

I've never really experienced on other boats, certainly not to this degree. I'm pondering some sort of twist shackle but I'm afraid of an accidental gybe breaking the twist shackle and allowing the boom to crash into the shrouds.
Is there another/better solution?
If not, any advise on a specific twist shackle?
Anybody want to speculate on the force applied to a twist-shackle with a 16kt accidental gybe with a main sail of 430 ft sq.

 

[JRacer]

Is that bottom block on the traveler set so it is free to spin?

 

[thinwater]

That is a twist, not a hockle.

A shackle with a swivel will not solve the problem. It will probably make it worse. You do NOT want a free-spinning shackle on the traveller; better off locked. Swivels are for alignment problems, not solving twist.

a. You are putting twists in the line when you coil it. Very easy to do, and they accumulate. Google coiling, and switch to figure 8 coils.

b. Sometimes the arrangement of blocks and pulleys can add twists, most often because the line skids when loose and tracks when tight.

But it is probably the coiling. Obviously, you can remove the twist you have by unreeving, taking the twist out of the line, and re-reeving. Easy. Tip: Instead of taking the line out of the mast, cut the dumb splice off the end on the boom. That does NOT need a splice, it's just for pretty.
Stopping sheet twist

 

[jssailem]

@thinwater nailed the problem and the solution.

Here are a couple additional ways of looking at the solution.

COILING ROPE: Figure Eights, Please - Wave Train

Brief tutorial on the advantages of coiling rope in a figure-eight pattern

wavetrain.net

 

[colemj]

If the block on the traveller can swivel, then fix it or replace it with a fixed block. A swiveling block there would be the #1 cause of twist.

Next would be coiling, as covered above.

After that would be the use of a winch for the mainsheet putting twist into the line.

Mark

 

[joelm100]

Excellent! and thanks all. The block at the traveler does swivel. I'll take a look at it next time I'm down there and see if I can lock it, else get one that doesn't swivel. Pretty sure it's not my coiling, 'cause I don't coil.

 

[rgranger]

a. You are putting twists in the line when you coil it. Very easy to do, and they accumulate. Google coiling, and switch to figure 8 coils.

I flake my lines.... similar concept to @thinwater 's figure-8

 

[dLj]

How new is the line? I've found new line often comes with a fair amount of twist in it. I will take new lines and lay them out straight and make sure there is not twist in the line. It helps to pull quite hard from one end that has a very easy to spin connection to the line so any twist will allow the line to spin. I've also done this by hand but that's a lot more work. If I have older lines that do this I'll also do the same thing. But I find it's more common in newer lines.

dj

 

[JRacer]

Another way to get out the twist. Throw the whole thing off the stern while sailing (not motoring) and let the tail drag behind the boat for a while. Then retrieve and properly coil.

 

[thinwater]

DLJ has a point about new line. Some folks trail a line to remove the twist, but it can be done in the cockpit, by spinning the tail a few times as you flake the line a few times. It normally takes a few goes.

If it is not coiling (even flaking can twist line, if you don't concentrate!), then look at the blocks coming out of the boom. Sometimes they put a twist in.

My suggestion is to un-reeve the tackle, pulling it toward you and back to get ALL of the twists out, and re-reeve. Then watch it and see if it is not obvious. And locking the swivels should actually help push the twist back out in the future. A swiveling base can help "trap" twist.

Finally, even with the best practices, twists can sneak in. Consider un-reeving occasionally to be maintenance. For example, even on the simple 7:1 tackle on my F-24, about twice a year I have to stretch it and then pull it block-to-block, usually twice, to force the twists out. I like fast-running tackles with zero twist.

Another trick that works with some lines. Anchor the bitter end. If the bitter end cannot twist, and the tackle end cannot twist, then there can be no net twist over the length of the line. Obvious? This is the standard method on most dinghies and beach cats, and it works.

 

[Stu Jackson]

Good points, tw.

I urge you all to go back to the OP's picture in the first post. The line itself may well not be twisted, but it sure is TWISTED AROUND ITSELF. Because of the swivelling block.

When I bought my then 12 year old boat in 1998, I noted that one of the mainsheet blocks had a LOT of twine around its base, locking it. My PO had also gifted me 11 years of Mainsheet magazine, one of which had an interesting article about the dangers of swivelling blocks and where they should NOT be employed.

This is nothing new. It's not the line itself that is twisted, it is twisted around itself. BIG difference. The swivelling base causes the line to wrap around itself, it does not necessarily cause twist "in" the line itself. i have bought miles of line oer the years and can't recall one instance of line twist.

A swiveling base can help "trap" twist.

 

[colemj]

You are right that the line is twisted on itself, not twisted internally. My response assumed we were talking about the line twisted on itself. Like you, I am positive this is caused by a swiveling block.

But improper coiling, or using a winch without taking the impressed twist out before releasing will also cause the line to twist about itself - as everyone with a 2:1 halyard has experienced.

Mark

 

[joelm100]

Quick report back: as I noted the block has been able to swivel. This weekend I put a new set screw in to stop that, but alas, not enough wind to see if it makes the difference. Thanks again all for making that recommendation. I’ll report back in a couple of weeks.