Rope clamps

andsarkit

Well-known member
Joined
27 Aug 2015
Messages
1,258
Location
Dartmouth
Visit site
How much torque could those fitting transfer, before the metal body slips against the internal rope/resin?
I have only seen such terminals for steel wire, the internal side was perfectly round and polished :(
You could probably attack the sides of the cone with a triangular file to add some grooves or even make it more a pyramid square shape. Some more information here: https://www.strider-resource.com/documents/resinsocketing.pdf
 

Neeves

Well-known member
Joined
20 Nov 2011
Messages
13,103
Location
Sydney, Australia.
Visit site
I don't think I would go for adhesive and shrink cover ... but I'm an old school deckie .. parcel and serve ... splice ... bind ... those sort of solutions ...
I too find it difficult (actually very, very difficult) to believe that a bit of adhesive and a shrink cover will offer the security needed for the application.

However I do know that if you apply red Loctite (or some red Loctites) to a shackle pin it is impossible to release (even using 2 big shifters) without resorting to a blow torch and other adhesives are similarly robust. I thus have to remain openminded.

In reading of the application I think there was mention made of 'S' clamps - but I could find no details nor a picture (so I have no idea what role they might play - I can guess, but guessing is inapplicable in this application). I don't want Zoidberg unceremoniously dumped over board by an angry foresail.

I'm also intrigued as the links imply that 2 reputable suppliers seem to back, one invented the other sells, the concept.

I'm trying to find more information but its a very niche application.

Jonathan
 

Refueler

Well-known member
Joined
13 Sep 2008
Messages
20,428
Location
Far away from hooray henrys
Visit site
The only S clamps I have seen have been in low stress situations and I think I still prefer the C clamp version. C clamp has both rope parts directly in contact and forcing significant friction to the joint.

TBH - I think I would be looking for a more workable length of rope !
 

Neeves

Well-known member
Joined
20 Nov 2011
Messages
13,103
Location
Sydney, Australia.
Visit site
The only S clamps I have seen have been in low stress situations and I think I still prefer the C clamp version. C clamp has both rope parts directly in contact and forcing significant friction to the joint.

TBH - I think I would be looking for a more workable length of rope !
The rope, the anti torque rope is the stay and part of the furler (if you like it replaces the foil). It thus has to be strong, similar in strength to the stay (it replaces) but cannot twist when you want to furl the sail round the rope.

So imagine a piece of steel reinforcing rod - attached to swivels top and bottom - that's the application of the anti torque rope. If it twists - it will not furl. If it is workable - it will twist.

If you now look at big racing yachts with a Code Zero they are furled and unfurled round their own anti torque 'stay'. There are a number of ways of achieving the ability to furl round 'itself' - anti torque ropes are but one. The OP mentions he has the torque rope - he must have 'won' it

The OP is taking the concept to allow him to furl a 'conventional' but small, inner, head sail. So imagine, again, a head sail furled round the piece of steel rod - when not in use there is no stay 'inside' the Jib/Genoa, so he can tack with ease. When he wants to use the 'inner' stay he lifts it with the, dyneema, halyard for the inner stay, grinds the tension in and unfurls the sail. Its simply a derivative of the Code Zero - applied to, say, a storm jib. If you are single handed in the Southern Ocean you can rig the whole think from the cockpit (as long as you have prepared in advance).

The anti torque rope is not totally inflexible, you can, sort of, bend it - like old fashioned radar cable, or reinforcing steel rod - but its about a coil 2m in diameter.

Our first screecher ( a sort of Code Zero) was Mylar with a torque rope. The Mylar fell apart under UV, a specific issue with Mylar in Oz, but I kept the anti torque rope for the luff. I made eyes using stay clamps - unsightly and might tear the sail - it worked but it was more sensible to buy a new sail (with a different method of furling round its own luff).

Sorry difficult to describe without lots of pictures (which I never took)

Jonathan
 

Neeves

Well-known member
Joined
20 Nov 2011
Messages
13,103
Location
Sydney, Australia.
Visit site
This how I solved the OPs problem. I had an old spinnaker and I tried to use the anti-torque rope as both a luff and stay, with the sail furling round the rope. It worked, sort of, but was darned ugly and really ugly when the spinnaker was furled. The rope is dense/tight and though the stay clamp is as tight as possible there is almost no compression of the rope. The whipping was an attempt the neaten it a bit - shrink covers would have been useful (but a bit of a waste)

IMG_0668.jpeg

The OP's problem is to make an eye when the rope is so dense you cannot sew, or not by hand. In my case I did think of drilling with a fine, very thin, drill bit. I thought of more whipping, I think it, whipping, might work with slightly thicker (than the blue whipping twine I had available) braided dyneema.

I did wonder about encasing the overlap in dyneema hollow tape and stretching the tape so that it locked onto the overlap - but getting it to reliably lock was one issue (and did not, do not, have tape big enough). If you take a double braid and bunch up the cover, the cover expands and you can slip it off. If you take the same cover and tension just the cover - it locks up - hence my idea of locking on a cover.

The link I gave, see earlier post, uses the tape idea but with glue and a shrink cover (there are very few original ideas - but lots of clever tweaks)

Jonathan
 

Neeves

Well-known member
Joined
20 Nov 2011
Messages
13,103
Location
Sydney, Australia.
Visit site
Sophisticated rope clamps for torque ropes

another Google search :)

Torque Rope Clamps — Colligo Marine

Jonathan

Few original ideas, lots of clever tweaks - resulting in expensive products :(

Take a metal tube (experiment for size) hammer to an oval shape (or distort in a decent engineers vice) file ends to present a smooth surface. Drill, tap and insert short, say 4mm dia, Alan keyed bolts. Insert overlapping torque cord (as in my picture above) apply Loctite, blue should suffice, insert and tighten bolts.

edit

You could use a series of copper ?, oval swages (the sort you would use on old fashioned wire halyards) maybe over shrink covers suitably drilled and tapped with LFRs for the eye. If you don't like the idea of the bolts damaging the rope then have 2 swages, one inside the other but don't drill the inside one simply tighten the bolts to compress the inner sleeve onto the internal overlapping rope.

J
 
Last edited:

Refueler

Well-known member
Joined
13 Sep 2008
Messages
20,428
Location
Far away from hooray henrys
Visit site
The rope, the anti torque rope is the stay and part of the furler (if you like it replaces the foil). It thus has to be strong, similar in strength to the stay (it replaces) but cannot twist when you want to furl the sail round the rope.

So imagine a piece of steel reinforcing rod - attached to swivels top and bottom - that's the application of the anti torque rope. If it twists - it will not furl. If it is workable - it will twist.

If you now look at big racing yachts with a Code Zero they are furled and unfurled round their own anti torque 'stay'. There are a number of ways of achieving the ability to furl round 'itself' - anti torque ropes are but one. The OP mentions he has the torque rope - he must have 'won' it

The OP is taking the concept to allow him to furl a 'conventional' but small, inner, head sail. So imagine, again, a head sail furled round the piece of steel rod - when not in use there is no stay 'inside' the Jib/Genoa, so he can tack with ease. When he wants to use the 'inner' stay he lifts it with the, dyneema, halyard for the inner stay, grinds the tension in and unfurls the sail. Its simply a derivative of the Code Zero - applied to, say, a storm jib. If you are single handed in the Southern Ocean you can rig the whole think from the cockpit (as long as you have prepared in advance).

The anti torque rope is not totally inflexible, you can, sort of, bend it - like old fashioned radar cable, or reinforcing steel rod - but its about a coil 2m in diameter.

Our first screecher ( a sort of Code Zero) was Mylar with a torque rope. The Mylar fell apart under UV, a specific issue with Mylar in Oz, but I kept the anti torque rope for the luff. I made eyes using stay clamps - unsightly and might tear the sail - it worked but it was more sensible to buy a new sail (with a different method of furling round its own luff).

Sorry difficult to describe without lots of pictures (which I never took)

Jonathan


I am aware of the OP's intended use and the torque effect etc.

It brings me back to memories of the Old Wykeham Marting furling .. (some think it also reefs - but WM say not - its for full or nothing furling !).
 

srm

Well-known member
Joined
16 May 2004
Messages
3,248
Location
Azores, Terceira.
Visit site
How about taking your rope and eyes to a fishermen's chandler that makes up commercial trawl gear etc. and ask them to make Talurit splices. I used to have flexible wire mooring ropes for oceanographic instruments made with these. Have also used it on 'combination rope', basically a fibre rope with wire cores.
Lots of pics of Talurit splices on Google but basically its a soft metal ferule (copper or other alloys) compressed around the rope. The bigger sizes use a hydraulic press.
 

Neeves

Well-known member
Joined
20 Nov 2011
Messages
13,103
Location
Sydney, Australia.
Visit site
For completeness this is the alternative for an unstayed headsail, call it a Code Zero or Screecher. I'd forgotten I had the picture. This is of no use to the OP as he already has the torque rope for his stay/luff.

IMG_2940.jpeg

This semi-circular device is custom made, I don't think too difficult to make oneself. Its basically half a sheave with a slot to accept the tape. There is another identical device at the head of the sail. The half sheave, or 2 half sheaves retain a continuous loop of dyneema separated as shown and sewn to act as the luff of the headsail. There is an identical swivel at the head, these are Ronstan swivels.

In use the halyard is bar tight which keeps the double dyneema luff loop separated and when the sail is furled the loop acts just like a standard foil and the sail furls round the loop.

Both the single torque rope or this system works well - the big issue is slippage of the dyneema or the halyard inside its cover when retained in a clutch (though newer designs of clutch might address this issue). The halyard is cranked right up, to ensure the luff of the sail is as straight as possible (allows pointing). The cover of the halyard is gripped but the core, or dyneema, is very slippery and the core has been known to slip catastrophically. An answer was to ensure the core was also gripped but minor slippage of the dyneema allowed the cover to take more tension (than the core) and the cover abraded and did fail. Having the core slip or the cover fail was not uncommon (been there, done that).

The answer was to leave the halyard on the winch - but this then tied up a winch.....Leaving on a winch is 'unnatural' and neophytes would often clear winches (as clearing winches would be standard practice). Impressing on crew to leave the screacher/Code Zero halyard on the winch was part of standard instruction. I was on a 43' cat whose halyard failed, as described. We had to cut the halyard to douse the sail - we later had to climb the mast to re-inset a new halyard.

Under tension when the sail was actually being used it was impossible, or very difficult, to furl the sail and commonly the tension of the halyard was eased slightly. Maybe better, think more expensive, swivels overcame this issue.

When the sail was furled it could be folded, loosely (you often see them lying on the deck as an untidy sausage). You don't want to pack them tightly as it distorts the fibres. They are thus not really very conducive for cruising as they take up a lot of room down below and will suffer from UV if left on deck. We left ours rigged, furled, as it had a UV strip - but either the sun was sufficient the times we used it (often, they are great sails) or the UV cover was not very good and life was short.

Nearly every modern, current, multihull will carry a screecher - unstayed headsails are common place. Off the wind a really satisfying sail, double digit boat speeds easy to achieve, huge bow spray and rooster tails

Jonathan
 

William_H

Well-known member
Joined
28 Jul 2003
Messages
13,987
Location
West Australia
Visit site
Back to OP question of fitting an eye splice into the end of the rope. I don't know the rope type but understand it is difficult splice or open up.
Perhaps no help but there is a technique used in dyneema where the rope is opened up near the eye to pass the tail from the eye through the hole in the rope. Then the tail is opened up with a hole nearby so the main part of rope length can be passed through that hole. When pulled tight you have a locking splice. From there with dyneema you can pull the tail inside the outer cover. Or just whip the tail onto the main part. Of course to fit an eye splice to both ends does require that you can feed one eye splice through the hole in the last tail. Works great with loose woven rope .
I would hate to have those metal clamps on my sheets. (or in fact on any rope) ol'will
 

zoidberg

Well-known member
Joined
12 Nov 2016
Messages
6,293
Visit site
Back to OP question of fitting an eye splice into the end of the rope. I don't know the rope type but understand it is difficult splice or open up.
Perhaps no help but there is a technique used in dyneema where the rope is opened up near the eye to pass the tail from the eye through the hole in the rope. Then the tail is opened up with a hole nearby so the main part of rope length can be passed through that hole. When pulled tight you have a locking splice. From there with dyneema you can pull the tail inside the outer cover. Or just whip the tail onto the main part. Of course to fit an eye splice to both ends does require that you can feed one eye splice through the hole in the last tail. Works great with loose woven rope .
I would hate to have those metal clamps on my sheets. (or in fact on any rope) ol'will
Thanks, William_H, for your suggestion.

What you describe is, I believe, a Locked Brummel Eye Splice.... with which I am quite familiar.... practicable in both single- and double-braid rope.
Regretably, that is quite impossible with Torque Rope due to the construction.
 

Roberto

Well-known member
Joined
20 Jul 2001
Messages
5,376
Location
Lorient/Paris
sybrancaleone.blogspot.com
I reckon an eye made by using 2-3... successive clamps of this type with 1 or 1.2mm stainless steel wire wound very tightly might be worth testing with a winch, a car, whatever you have to create a high load.
Just tried with a piece of line I had at home, 2x8mm rope total 1sqcm can be easily compressed to about 0.7sqcm, I reckon more with thicker wire.
No idea of the load it could bear but it looks neat :)

Eye (2).jpg
Eye (1).jpg

Eye.jpg
 

thinwater

Well-known member
Joined
12 Dec 2013
Messages
4,850
Location
Deale, MD, USA
sail-delmarva.blogspot.com
This is what was actually posted about splicing the torsion rope by Kohlhoff. I'm not sayin' I understand it, but it is not just glue. I might guess that the adhesive is something like the Amsteel coating (a polyurethane adhesive). I've never experimented with using hollow braid to secure an eye splice, but it sounds interesting. It works in a clutch and in single braid splices. But my guess is that there are simpler ways to splice most ropes and this only makes sense for certain unsplicable, unsewable ropes.

1710363226533.png
 
Top