Ultra sling vs deadeye: double the strength?

[Muggs]

I have long wondered how much the bury affects the strength, behind the 2 locking brummels...

 

[Brocky]

Another splice to consider is Samson’s Tuck-Bury for class II ropes. I’ve had several tested and they broke at 98 1/2%.

 

[Matias]

I have long wondered how much the bury affects the strength, behind the 2 locking brummels...

HowNot2 has a video where they do a locking brummel on dyneema, but with no bury and it pulls out at frighteningly low force. I'll go dig it up.

 

[Matias]

so I was wrong, they do a one fid bury and it slips out at half the MBS

 

[john.massing]

Another splice to consider is Samson’s Tuck-Bury for class II ropes. I’ve had several tested and they broke at 98 1/2%.

Is that the same as what is elsewhere referred to as a straight bury, just with a longer bury because it is class 2?

 

[Brocky]

No, it only takes one and a half fids of bury of half the core, the other half gets tucked along the outside. Possibility a class I wouldn’t need even that much.

 

[Brocky]

so I was wrong, they do a one fid bury and it slips out at half the MBS

A fid and a half retains 75%, no bury, generally 50%.

 

[Muggs]

@Matias

Yeah but I have a hard time believing this affects type 1 fibres in the same way... don't they say that dyneema is as slippery as teflon?

 

[Matias]

Yea, that is confirmed in the video basically. I think the big take away is that the shittiest splice, as long as you are trying to get it right, will hold at least as much as a good knot, so just start splicing and work towards perfection, but don't stress if it isn't perfect.

 

[Matias]

Yeah but I have a hard time believing this affects type 1 fibres in the same way... don't they say that dyneema is as slippery as teflon?

almost as slippery, but close. and yea, I believe that polyester would perform much better

 

[evo]

HowNot2 has a video where they do a locking brummel on dyneema, but with no bury and it pulls out at frighteningly low force. I'll go dig it up.

That’s to be 100% expected with dyneema. It’s slippery as f and requires something like 3.5x the bury length of polyester

 

[john.massing]

Samson recommends full bury, it is supposed to be stronger. I don't think their splicing manual even shows how to do brummels. Really looking forward to seeing the results from your deadeyes John.

These are a couple of Samson mentions of brummels. Though neither are stand alone instructions and the whoopie has no taper. The whoopie I had broken broke at about 89% of the ABS and it broke right at the end of the bury which is the same point that the adjustment leg exits.

 

[evo]

Weak link, fiber disruption…

 

[john.massing]

I posted all of the break test results and photos in a new thread.

Break test results of various rigging slings constructed of 12 strand hollow braid

These are break test results. The dead eyes and eye and eye were tested in a straight pull configuration. The ultra/pocket, loopie, and whoopie slings were girthed onto a 4" bollard similar to their intended uses.

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