Dynemma eye splice brummel lock

[Gsailor]

As in this video:

dyneema eye splice - Google Search

Is this eye 100% secure from slippage? It looks good to me.

I have been told to stitch the bury or stitch near the eye but is that necessary?

 

[Neeves]

I've been burying from both ends and some of my buries have been short - so I have sewn where the 2 buries meet in the middle using braided dyneema fishing line. I have also made some double buries, all the way through, with eyes at both ends with x70 buries and have still sewn (I like certainty). If you sew, anywhere, it will be difficult to take apart. If you sew at the eye and if its a buried eye you will lose the ability to open the eye.

The ideal is to test your splice if its in a critical application - but testing is not easy for most. The difficult part, if you want to make soft shackles, is testing the integrity of the button knot - which determines the strength of the shackle.

I have been using offcuts from my own rigging, where the cover has worn. I have stripped off the cover and used the dyneema core.

You local chandler may have end of reel in a bin slightly cheaper than normal retail. But the colour is what you get.

If you use the search function on YBW - you will find a wealth of information.

Jonathan

 

[Gsailor]

I've been burying from both ends and some of my buries have been short - so I have sewn where the 2 buries meet in the middle using braided dyneema fishing line. I have also made some double buries, all the way through, with eyes at both ends with x70 buries and have still sewn (I like certainty). If you sew, anywhere, it will be difficult to take apart. If you sew at the eye and if its a buried eye you will lose the ability to open the eye.

The ideal is to test your splice if its in a critical application - but testing is not easy for most. The difficult part, if you want to make soft shackles, is testing the integrity of the button knot - which determines the strength of the shackle.

I have been using offcuts from my own rigging, where the cover has worn. I have stripped off the cover and used the dyneema core.

You local chandler may have end of reel in a bin slightly cheaper than normal retail. But the colour is what you get.

If you use the search function on YBW - you will find a wealth of information.

Jonathan

Sorry for being thick, but you are saying that the eye as seen in the video could slip and come undone?

Not talking about soft shackles here obviously.

Are you saying you would not make an eye like that and place your life upon it?

I thought it was a locking eye that could not possibly come undone.

 

[Neeves]

Sorry for being thick, but you are saying that the eye as seen in the video could slip and come undone?

Not talking about soft shackles here obviously.

Are you saying you would not make an eye like that and place your life upon it?

I thought it was a locking eye that could not possibly come undone.

I'm saying I would not place my life on an eye, I, or anyone, made without it being checked for strength. None of my splices are in life security environments - if it was life security I would use a tested bit of kit backed up by a company with a reputation. None of my splices, not like the one in the vid, are used in life dependent situations and until you have yours tested I'd suggest you might like to consider the same caution. If I'm up a mast I use tested climbing kit, my anchor chain, hardly securing my life, is tested (independently). Why do you think your splicing will be sufficiently secure to risk your or that of anyone in your crew.

It might secure a sail - but that is entirely different.

Just because something on a vid is tested does not mean you will achieve the same result - you might - but until its tested you and we will not know.

Jonathan

 

[RJJ]

I would and have used dyneema eye splices on jackstays.

The key is the brummel being correctly secured and the length of the bury, 72 diameters including the taper, if I remember right.

 

[Neeves]

The question asked was would I place my life on a splice made by a man who has never made this splice and is relying on following a video to effect his work.

My answer is - No.

I don't know the man or woman from a bar of soap. I don't know if he is happy with 'It'll be alright'. I don't know his source of dyneema.

Now once he has a reputation for a splice, he has used it and ironed out any issues - different story. In the meantime I'd sew - belt and braces. I'd sew anyway. And in a life dependent situation I'd be much more comfortable with a bit of kit from a reputable brand, Harken, Lewmar, Marlow. For a jackstay I'd prefer something with a bit more give than dyneema and I'd use tape and have it sewn by a sailmaker who knows the application.

Jonathan

The recommendation is 72 times diameter. With 10mm rope that's a very long splice.

Long Bury Splice

I'm lazy and use 70 - and sew and I have been trying not to taper - but it is hard work (but then I am burying from both ends). I have also been making splices with eyes at both ends and have not enough cordage to allow 72 times and I have been sewing the overlap (and placing a shrink cover to protect the stitching) - but not in an application where my life depends on it.

J

 

[GHA]

Sorry for being thick, but you are saying that the eye as seen in the video could slip and come undone?

Not talking about soft shackles here obviously.

Are you saying you would not make an eye like that and place your life upon it?

I thought it was a locking eye that could not possibly come undone.

This is a great forum for many things but not really the place for structural engineering / rope access techniques.
Be careful!

 

[Sumara of Weymouth]

With regard to testing a splice, there is a bit of a problem. If you lightly load the splice it wont really tell you much, a bad splice may hold under a light load. If you test under a high load, then you may damage the splice so it fails when in use. You can destruction test several samples out of a batch which, if they all fail at the correctly calculated strain, will give you an idea of the breaking load for the rest of the batch. From there you can decide on your safety factor to give your Working Load Limit. Proof loading is really a thing of the past. Ferrule secured wire rope eyes issued with full certification for lifting purposes are never proof loaded. The manufacturer ensures the correct ferrule is used on the correct wire and the final ferrule dimension after compression is checked to be within tolerance. So as Neeves has pointed out, it is probably safer to purchase a rope assembly from an established ISO 9001 compliant company if the consequences of a failure are liable to cause an injury. Trying to test your own work is just too complicated.

 

[roaringgirl]

If I understood the original question correctly, then the answer is that if you correctly splice a locking eye, the splice can only fail by ripping through the whole braid of the tail.

 

[Gsailor]

Thanks. Interesting comments.

 

[thinwater]

This is simple.

A Brummel (in the video) is an alternate method to stitching. Either locks the bury under low load until the Chinese finger trap effect takes the load. Splice fanatics will argue that one method is stronger than the other (sewn is slightly stronger), but they are within 5% so it matters little.

The bury in the video is too short. This is common in videos, because it makes the filming more manageable. That's unfortunate but very common. 72:1 is the gold standard, 50:1 tests just as well. Either way, the bury should have been about 10-15 inches. This is why short strops are typically loops that are seized at the ends.

It is really hard to do a bury splice wrong, if you follow the few basic rules. A whoopee sling is a clear demonstration of how reliable the contraction is. Simpler than tying a bowline.

 

[Gsailor]

Noted. Thank you

 

[Gsailor]

It is stated that for life or death situations only use products with a good reputation.

Makes sense. Although if dead I could not sue anyone. ?

But I once had a 30 foot boat moored fore and aft.

The moorings were anchors; one forward and one aft with the tide.

The anchors were attached to what looked like 30mm nylon that the harbour master had spliced soft eyes into around the anchor shackle.

Secluded bay and all was well.

QUESTION:
Does dyneema act differently, slippage etc from rough nylon? The splicing the harbour master did would have been good (although not a long length of splice and no stitching but the material would have been very cheap).

I am trying to understand the differences in materials.

 

[thinwater]

It is stated that for life or death situations only use products with a good reputation.

Makes sense. Although if dead I could not sue anyone. ?

But I once had a 30 foot boat moored fore and aft.

The moorings were anchors; one forward and one aft with the tide.

The anchors were attached to what looked like 30mm nylon that the harbour master had spliced soft eyes into around the anchor shackle.

Secluded bay and all was well.

QUESTION:
Does dyneema act differently, slippage etc from rough nylon? The splicing the harbour master did would have been good (although not a long length of splice and no stitching but the material would have been very cheap).

I am trying to understand the differences in materials.

Yes, Dyneema is slightly different to splice. Read Samson's splicing advice on class 1 vs. class 2 splices.

Ropes manufactured using the traditional fibers of nylon, polyester, and olefin are categorized as Class I. Those ropes, made in whole or in part with any of the high-modulus fibers, are categorized as Class II.

For example, the bury lendgths are different on class 1 vs. class 2 eye splices (50% longer).
How to Splice Rope - Samson Rope

Double braid, 3-strand, and hollow braid are, of course, completely different to splice, thought the principles of friction are unchanged. Double braid and covered Dyneema are also different.

 

[Gsailor]

Yes, Dyneema is slightly different to splice. Read Samson's splicing advice on class 1 vs. class 2 splices.

Ropes manufactured using the traditional fibers of nylon, polyester, and olefin are categorized as Class I. Those ropes, made in whole or in part with any of the high-modulus fibers, are categorized as Class II.

For example, the bury lendgths are different on class 1 vs. class 2 eye splices (50% longer).
How to Splice Rope - Samson Rope

Double braid, 3-strand, and hollow braid are, of course, completely different to splice, thought the principles of friction are unchanged. Double braid and covered Dyneema are also different.

Ok. A lot to learn.

Thank you.

 

[Neeves]

Dyneema has been given a refreshing new lease of life primarily due to soft shackles and things like LFRs. Its characteristics are it is very slippery, hence the longer bury, it is very strong, it is UV and abrasion resistant and it has no elasticity. It is a wonder fibre. People tend to forget some of these 'assets' and are using dyneema in applications that are inappropriate (and/or) a waste of money where other fibres would be perfectly suitable and possibly better at much lower cost.

I think if you are experimenting (which should be applauded) then describe the application and you may have a more fruitful discussion. If you don't actually have an application but are simply looking at different splices - then raise a thread on how these splices are used - and are the applications appropriate for dyneema.

You will break new ground as I don't recall a thread comparing use of dyneema vs polyester vs etc and the appropriate splices.

Jonathan

 

[Gsailor]

Dyneema has been given a refreshing new lease of life primarily due to soft shackles and things like LFRs. Its characteristics are it is very slippery, hence the longer bury, it is very strong, it is UV and abrasion resistant and it has no elasticity. It is a wonder fibre. People tend to forget some of these 'assets' and are using dyneema in applications that are inappropriate (and/or) a waste of money where other fibres would be perfectly suitable and possibly better at much lower cost.

I think if you are experimenting (which should be applauded) then describe the application and you may have a more fruitful discussion. If you don't actually have an application but are simply looking at different splices - then raise a thread on how these splices are used - and are the applications appropriate for dyneema.

You will break new ground as I don't recall a thread comparing use of dyneema vs polyester vs etc and the appropriate splices.

Jonathan

Thanks.

My first like, is that it is SO easy to use and splice... so much easy than crown head knots etc on'old' rope.

That is a huge plus to me.

I now need to find tutorials on how to stitch the stuff and then I may be sorted.

Benefits of using it? Ease of manipulation. Strength per unit diameter. Lightweight.

 

[Neeves]

Thanks.

My first like, is that it is SO easy to use and splice... so much easy than crown head knots etc on'old' rope.

That is a huge plus to me.

I now need to find tutorials on how to stitch the stuff and then I may be sorted.

Benefits of using it? Ease of manipulation. Strength per unit diameter. Lightweight.

An example of where use of dyneema lacks logic - soft shackle to hold up coiled sheets, etc neatly - polyester would do just as well - and yes - I have heard it suggested (and even less logical uses). Once you get to small sizes, small diameters, its easier to splice larger diameters (which could be dyneema) or polyester. I'm using wasted short lengths of dyneema - for which I cannot conjure up a use (except to hold fenders (dyneema to hold a fender???). Currently 4mm, dyneema (it was 5 or 6mm with a polyester cover) is defeating me but I'll persevere. Small diameter dyneema is immensely strong - but a devil to handle

As with many things on a yacht - compromises.

This may be behind a paywall but try this for stitching

Stitching Instead of Splicing - Practical Sailor

Its all tested, its concise. If you cannot access - then start a thread on stitching - you may find someone here has the answers.

Jonathan

 

[thinwater]

I few days ago I needed a strop about 10 inches long to hold a low friction ring, working load about 100 pounds (a fairlead with a very small deflection angle).

I spliced it from 5/16" polyester cover-only, using single braid methods. The cover flattens out nicely in the LFR groove. Dyneema would have been too narrow. I could also have hand stitched it from webbing, in even less time, and that would have worked. Many methods.

 

[roaringgirl]

I decided *not* to make soft shackles out of anything other than HMWPE so as to avoid anyone accidentally using a weaker one in a high load application. HMWPE cost per shackle is low.