Amsteel Blue Continuous Loops - locked brummel vs lock stitch

[Amsteelbluez]

Read this in sailing anarchy forum and it makes sense. Perhaps the fails were from tight locks?


The trick is that you don't want the brummel lock to load up in normal conditions. Rather you want the splice to behave like a direct-bury and the brummel is only there to prevent accidental pull-out of the buried tail under no-load conditions. To ensure that the brummel doesn't load up, don't tighten up the lock before you bury the tail. Leave in loose and leave a bit of a gap between the locks and the entry point for the bury. Then when filing down the bur, make sure that the locks are still separated. Doing it this way allows the splice to slip and settle a bit while it beds in without the brummel locks getting loaded up and breaking.

I hope this makes sense...

[Benz]

Originally Posted by Amsteelbluez

Read this in sailing anarchy forum and it makes sense. Perhaps the fails were from tight locks?


The trick is that you don't want the brummel lock to load up in normal conditions. Rather you want the splice to behave like a direct-bury and the brummel is only there to prevent accidental pull-out of the buried tail under no-load conditions. To ensure that the brummel doesn't load up, don't tighten up the lock before you bury the tail. Leave in loose and leave a bit of a gap between the locks and the entry point for the bury. Then when filing down the bur, make sure that the locks are still separated. Doing it this way allows the splice to slip and settle a bit while it beds in without the brummel locks getting loaded up and breaking.

I hope this makes sense...

I have pulled, with an hydraulic ram, scores of brummeled eye splices, and have seen no advantage to making a sloppy brummel as this paragraph advocates. Make it tight, start your bury close: the bury, if done tidily, will always take up the load. Also, what does it mean by "when filing down the bur"? That doesn't sound like splicing at all.

[boat driver]

Originally Posted by Benz

^^What does the phrase "in limited length space and continuous length" mean?
Any chance you could explain further?

I stand corrected- the clipper race was the failure that killed the crewmember- it was a while ago-

the specific failure was the use of one line, Brummel splice to make two legs. it was done due to limited space between the splice and the deck that would not support the length of a buried splice.

Over time, the load/release creates heat which microhardens the fibers- and thereby then they become brittle and weaken. This is the simplest explanation.

The public perception and folklore is who needs that strength (6mm-60K lbs) on lifting a dingy etc.
Most Brummel lock discussions are valid but often limited understanding of proper use application. Individual applications need to recognize what is happening and why- If, as in the case of the Clipper race, the professional application considered strength, limited space, and results- but failed to account for the internal load/release cycle. And this discussion extends to the materials used in lifelines, rigging, etc.
The use of synthetic and brummel splices in lifting one designs is common- ease of making the sling etc, but if getting age on them, sUV exposure, and many lifts, look closely with a magnifying glass and localized discoloration/abrasion may be noticed.

[fxykty]

Originally Posted by boat driver

…

the specific failure was the use of one line, Brummel splice to make two legs...

OK, so this incident has nothing to do with using a Brummel lock in an eye splice - we can all relax.

[sailingharry]

Originally Posted by boat driver

The public perception and folklore is who needs that strength (6mm-60K lbs) on lifting a dingy etc.

Just for clarity, 6mm dyneema runs around 7,500lbs, not 60,000lbs.

[thinwater]

Originally Posted by boat driver

... But the significant break that killed a crewmember on the Volvo? Race was a vang stopper- the hitch was used in limited length space and continuous length. and after multiples of load/unloading it let go under load at the splice....

I like stitched splices, and with care the stitching should be invisable. In fact, I was picking out a few 7-year old splices last night and it was tuf to find the stiches. Even so, it was easier than undoing the Brummel, when I could not get to the end.


And BTW, the stiched eye was perfect, but the brummel eye had one yarn nearly chafed through, inside, where I had not seen it during inspections (shroud tensioner). No more brummels for me.

The Clipper splice broke because it was ONLY a Brummel and no bury. I believe it was a preventer bridle. Not a fair comparison and should not sully the Brummel name.

[Iron E]

Originally Posted by sailingharry

6mm dyneema runs around 7,500lbs, not 60,000lbs.

Goals

[s/v Jedi]

Just so this stops, 6mm Amsteel Blue is 8,600 lbs avg strength.

[Leadfree]

This example is one that I've replaced, so it's shaggy. But it is a good example of the proper way to do a grommet, and Brian Toss' WORKING ROPE: BASIC BRAIDED SPLICES is an excellent primer

[s/v Jedi]

Originally Posted by Leadfree

This example is one that I've replaced, so it's shaggy. But it is a good example of the proper way to do a grommet, and Brian Toss' WORKING ROPE: BASIC BRAIDED SPLICES is an excellent primer

So did you re-braid it for the Brummel?

[peb]

Originally Posted by Benz

The brummel weakens the splice a little, but unless you're winding up the load to dangerously near failure, it's not significant. I usually brummel uncovered eye splices like that: it gives the eye definition, and locks it in size while you make the rest of the splice. I still put a whipping on the splice throat to keep the tail from trying to wiggle back when it's unloaded.
Lock-stitching can look bulky if done with too large a twine, and untidy if not carefully done: a brummel and whip looks a lot better IMO.

I did not think the brummel really weaken the splice at all, since the weakening due to the brummel distortion is more than made up by the fact that there are two legs at that point in the splice. At the end of the day, it does not matter who is right, but it is important to understand the theory of how these splices work IMO.

You are correct that in a continuous loop, a brummel is certainly not to be used. Basically, the brummel is only used in an eye-splice of uncovered line. And for dyneema, IMO, I agree with you it is the preferred solution.

[Amsteelbluez]

Originally Posted by Ween

Aha, I see why you have a big lump. In a traditional brummel in a loop the second pass-through would be in a loop leg not and end (loose) leg. This can only be done by re-weaving the line around the loop. Never seen your way done before. Guess it is OK for small line to might be using? 4mm?

I can only imagine you'd be ok in your application just doing deep buries and whip a bit to lock when not under load.

Ween,
Do you have info on creating the locked brummel you mentioned? I'd like to learn this

[s/v Jedi]

Originally Posted by Amsteelbluez

Ween,
Do you have info on creating the locked brummel you mentioned? I'd like to learn this

I think the method was originally developed by Brion Toss. Here is an example; the guy also has a video on YouTube: https://www.riggingdoctor.com/life-a...neema-deadeyes

[Amsteelbluez]

Ah I see. Unravel and braid. Gotcha.

I have someone asking for 8" diameter loop. With 7/16, the tail bury is only around 13.5", not 3 fid lengths (27.5")

How do you deal with that? Not make it since you can't bury 3 fid lengths?

It will be used with LFRs, with working load around 2500lbs

[Benz]

Originally Posted by Amsteelbluez

Ah I see. Unravel and braid. Gotcha.

I have someone asking for 8" diameter loop. With 7/16, the tail bury is only around 13.5", not 3 fid lengths (27.5")

How do you deal with that? Not make it since you can't bury 3 fid lengths?

It will be used with LFRs, with working load around 2500lbs

There's several ways:

If you make a plain loop (like the thread here is about), you just bury as much as you have room for, and overlap the tail tapers so that the diameter stays continuous. Remember you have two buries, not one, in that splice, so 3fid is not really needed. Because the bury is going around the bearing points, it's also less likely to slip. I have a 5" loop made out of 1/2" that I pulled super-hard and it hasn't moved.

A better way to make small loops is to make a selvagee inside a cover. That's several passes of smaller material, placed inside a protective dyneema cover. I'd do 3 passes of 3mm Marlow Lashline inside an 8mm cover. Here's a link to instructions for that on my website:
https://zartmancruising.com/zartman-...-dyneema-loop/