Rope clamps

[zoidberg]

I find myself with a length of Marlow Profurl 2 11mm torque rope, which cannot have eye-splices formed due to the structure/density of the rope. It is possible to 'sew' an eyesplice in, but that requires a very expensive commercial machine and a similarly-expensive trained operator. Milady is not up for that!
The other approach is the use of proprietary rope clamps - Selden, Colligo, Wichard, Karver - all of which are eye-wateringly expensive.

Any better ( aka cheaper ) alternatives?

 

[Refueler]

Do you mean Marlow ProDrive 2 ?

Depending on the load you are expecting to cover with your 'eye' - if its not extreme - what about binding the eye ? Fold round the thimble sufficient length - and then tightly bind the two together - done well - you'd be surprised at how much load that can take. The load is taken by the two parts friction ...

Another form is using split collars ... basically sheet metal cut into strips and then bent into a 'ring' - passed over the two ropes and then pressed to form a clamp. One close up to thimble and then a number along the two parts to secure. You can see these used on tow-ropes and so on ... but IMHO unless of good quality - less able than the 'binding' method.

 

[Poignard]

This way?

https://ropeworks.biz/reader/seizing.pdf

Good enough for 'Cutty Sark'!

 

[Sandy]

I find myself with a length of Marlow Profurl 2 11mm torque rope, which cannot have eye-splices formed due to the structure/density of the rope. It is possible to 'sew' an eyesplice in, but that requires a very expensive commercial machine and a similarly-expensive trained operator. Milady is not up for that!
The other approach is the use of proprietary rope clamps - Selden, Colligo, Wichard, Karver - all of which are eye-wateringly expensive.

Any better ( aka cheaper ) alternatives?

Speak to man in orange bunt.

 

[zoidberg]

Thanks, P. That's a helpful and detailed exposition. I'll likely try that and find a way to test-under-load.

 

[billyfish]

I've done it with needle and thread...by hand.

 

[JFowler]

I have whipped and sewn eye splices on my Traveller control line. Never had a problem.

 

[thinwater]

Thanks, P. That's a helpful and detailed exposition. I'll likely try that and find a way to test-under-load.

Please share what the application is. We're all curious. That line is pretty stiff.

Sewn eyes can be made by hand, and the strength is not that hard to gauge. Make a few stitches, break it, and then multiply from there. I've done a LOT of swn eye testing. But I'm not sure you can penetrate the core of that rope. I think it is very hard. No experience.

Seizing strength is extremely dependent on how tight the seizing are. With nylon it is practical impossible to get it strong, because the rope shrinks (stretches) under high load. This rope does not stretch, so possible. But you will need to use a serving mallet and it will be hard woork, but probably the best option. Many will say it is easy, but did they actually test the rope at 30-50% load? Very likely they were are very low load.

I'll bet dinner those Cutty Sark seizings were done by a pro with a mallet. They look TIGHT.

 

[zoidberg]

Please share what the application is. We're all curious. That line is pretty stiff.

I'll bet dinner those Cutty Sark seizings were done by a pro with a mallet. They look TIGHT.

Aye, that, Drewe. A GOOD pro.....

And given your predilection for testing such stuff, I'm pleased you've popped your head up.

OK. In at the deep end.

I have two headsails on furlers, on a 'slutter' rig. I want to be able to rig a storm jib, and dowse it again without the need to go crawling on the foredeck. I already have a good unused 'inherited' storm jib and want to retro-fit it so I can hoist it furled, like a small Code Zero, use it and furl it away again when it gets up to 'Prayer Mat' time.
I have a robust mast fitting a bit above the spreaders and the tack will clip onto the inner f'stay deck fitting.
I also have acquired a sufficient length of 11mm ProDrive 2 torque rope, which is way more than up to the task. I'm looking to achieve >1.5T Break or Fail Load.
I don't want to fork out upstream of £200 for the clamps.

The Karver KRE clamp device looks very suitable, until one looks at the cost.

I've tried sewing an eye into a 10.5mm Tutus Static Rope and found it impossible to penetrate. The Marlow torque rope I have would clearly be even harder to work, unless I utilise a powered drill and insert a series of 2.5mm through bolts. I'm also considering a group of thin steel clamps set using a hefty hand-hydraulic crimp press.
Then there's seizing, but using a table and seizing mallet.

In this application, I'd want the confidence that the resultant pair of eyes would withstand the loads. I can incorporate Dyneema 'fuses' into the setup, but the eyes/connectors I make in the ProDrive stuff should not fail. I don't want to find myself dancing on a wildly-cavorting foredeck trying to capture a wildly-thrashing freeflying storm jib.

 

[MontyMariner]

Use an Awl to stitch, then taper and whip it.
Then use heat shrink if your wipping is crap!

 

[thinwater]

Re.Tutus, it can take some force. Stitching palms are traditional, but pressing the rope into the needle, backed by a block of wood, is easier for rope. But my guess is that neither this nor an awl will work on torque rope. If it would, they wouldn't bother with clamps, at least not on one end.

Good heat shrink can help with UV. Or leather or webbing.

 

[Stemar]

Could you use a double figure of eight knot

and seize the end to the standing part? That would never slip.

I suggested a FoE rather than a bowline as I got thoroughly told off when I tied a bowline in a climbing rope once. I understand that the bowline can slip under serious loads, and may weaken the line more than the FoE. Not that that's likely to be an issue for your proposed use

 

[andsarkit]

I have used seismic strings (2.4km long) that had a kevlar (?) strain member core. The 4 sections were joined with a metal fitting with an internal conical hole. The core was inserted through the small end and fanned out inside the cone and then potted in epoxy resin. This was towed behind an SRN6 hovercraft at full power and we never had a failure of the join. If you could get an aluminium fitting machined up cheaply this could work for you as long as the torque rope could be fanned out sufficiently.

 

[Refueler]

I have used seismic strings (2.4km long) that had a kevlar (?) strain member core. The 4 sections were joined with a metal fitting with an internal conical hole. The core was inserted through the small end and fanned out inside the cone and then potted in epoxy resin. This was towed behind an SRN6 hovercraft at full power and we never had a failure of the join. If you could get an aluminium fitting machined up cheaply this could work for you as long as the torque rope could be fanned out sufficiently.

Most ships stores cranes aft have similar for their hooks .... cable is passed through and then locked by resin and then plugged.

If the core can be splayed - what about a Sta-lok or similar ?

 

[Neeves]

Could you use a double figure of eight knot
View attachment 173721
and seize the end to the standing part? That would never slip.

I suggested a FoE rather than a bowline as I got thoroughly told off when I tied a bowline in a climbing rope once. I understand that the bowline can slip under serious loads, and may weaken the line more than the FoE. Not that that's likely to be an issue for your proposed use

Torque rope has the flexibility or tactility of a game fishing rod, old fashioned radar cable or steel reinforcing rod. You can make an eye - but not close it (as would be needed in a knot).

Its very like trying to make a small neat eye in steel reinforcing rod (but without the ability to weld ).

Wire clamps, those 'U' shaped devices secured with 2 nuts would work - but are clumsy. The Cutty Sark idea might work but would need testing (as would any other idea). Its not a unique problem - its getting the ideas that are the most practical - and then working through them. I did what the OP wants using the 'U' shaped clamp things for wire - there must be a neater way (anti torque ropes for unstayed sails on furlers, Code Zeros etc, is not uncommon).

Jonathan

 

[Roberto]

I have used seismic strings (2.4km long) that had a kevlar (?) strain member core. The 4 sections were joined with a metal fitting with an internal conical hole. The core was inserted through the small end and fanned out inside the cone and then potted in epoxy resin. This was towed behind an SRN6 hovercraft at full power and we never had a failure of the join. If you could get an aluminium fitting machined up cheaply this could work for you as long as the torque rope could be fanned out sufficiently.

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

 

[Roberto]

I find myself with a length of Marlow Profurl 2 11mm torque rope, which cannot have eye-splices formed due to the structure/density of the rope. It is possible to 'sew' an eyesplice in, but that requires a very expensive commercial machine and a similarly-expensive trained operator. Milady is not up for that!
The other approach is the use of proprietary rope clamps - Selden, Colligo, Wichard, Karver - all of which are eye-wateringly expensive.

Any better ( aka cheaper ) alternatives?

Not sure about critical applications but you might try this sort of device


The original idea (I think) is this "Clamptite" from the US (lots of Youtube videos)
Clamptite Tools
having it delivered to Europe makes it very expensive so I made my own version following YT instructions about modifying a turnbuckle, very easy.
It comes handy in a number of ways, I use it for example for mooring rope end seizing, mine are 18mm to 22mm, these wire clamps compress the rope well below its diameter even when stretched, just flatten the wire "end knot" with a screwdriver and you can forget it, the rope runs as if it was seized with normal thin rope. Advantage it does not break/untie itself and the rope never unravels at the wrong moment, sometimes it happens with forgotten old rope seizings.
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.

 

[thinwater]

Could you use a double figure of eight knot
View attachment 173721
and seize the end to the standing part? That would never slip.

I suggested a FoE rather than a bowline as I got thoroughly told off when I tied a bowline in a climbing rope once. I understand that the bowline can slip under serious loads, and may weaken the line more than the FoE. Not that that's likely to be an issue for your proposed use

The person that told you off was an idiot, or at least pedantic, depending on the purpose. A bowline will not slip under load, though it does weaken the line slightly more and can loosen in certain oscillating loads, although this is very uncommon or it could not be used on jib sheets. And a climber would tie a back-up knot to secure the tail. It depends on the use. Not for tie-in knots, but often around objects.

But torque rope is seriously stiff and a knot would be a nightmare IMO.

 

[Neeves]

I did a google search and this is a neat solution (I note the OP has some endearing Scots straits and I confess I don't know how much the solution costs).

https://www.upffront.com/torsion-rope-489

The solution seems to rely on a shrink cover and adhesive. A further search uncovered a possibility that DSM has (had?) an adhesive for Dyneema as did Loctite, but neither were focussed at the OP's dilemma - but fabric. Refueler has mentioned that a solution might rely on the friction between two pieces of the rope and a shrink cover + adhesive (or whipping with dyneema thread might work).

Jonathan

and also

Kohlhoff Rigging DynIce furling rope 11mm x 15m at Upffront

 

[Refueler]

I did a google search and this is a neat solution (I note the OP has some endearing Scots straits and I confess I don't know how much the solution costs).

https://www.upffront.com/torsion-rope-489

The solution seems to rely on a shrink cover and adhesive. A further search uncovered a possibility that DSM has (had?) an adhesive for Dyneema as did Loctite, but neither were focussed at the OP's dilemma - but fabric. Refueler has mentioned that a solution might rely on the friction between two pieces of the rope and a shrink cover + adhesive (or whipping with dyneema thread might work).

Jonathan

and also

Kohlhoff Rigging DynIce furling rope 11mm x 15m at Upffront

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 ...