amount of bury for eye splice versus strength

[gkny]

I am curious about the relationship between the line diameter and the amount of bury that is required. I have some 1/2" dyneema that I want to use for the part of some mooring penants that go from the cleats through the chock and luggage tag onto nylon mooring lines. I am trying to keep them short.
I bought the large diameter for the extra protection against chafe rather than strength per se. I probably don't need the full strength of the line but figure that the amount of bury is not linear to the strength that it provides. Is there a rule of thumb for how much bury you need to get a certain amount of strength?

 

[SloopJonB]

Depends on the material.

Dyneema requires a long bury because it's so slippery (I presume).

Go with the amount recommended by the manufacturer.

 

[Kenny Dumas]

And stitch it for cyclical loads especially

 

[ryley]

I've heard that with a brummel with no bury it's about 50% of line strength, 30 diameters is 25% loss, and 60 is around 5-10% loss. But Kenny has it right,regardless, stitch it for this application.

 

[CaptainAhab]

This guy's channel is very cool. Dyneema often fails because of friction melting. The diameter of the pin for an eye can also cause abnormal results.

Your 1/2" Dyneema is good for 34,000lbs. You can afford to lose a bit. Lockstich it.

 

[SloopJonB]

I've heard that with a brummel with no bury it's about 50% of line strength, 30 diameters is 25% loss, and 60 is around 5-10% loss. But Kenny has it right,regardless, stitch it for this application.

30 inches of bury for 1/2" line

 

[ryley]

30 inches of bury for 1/2" line

Brion Toss's recommendation was 72 diameters. Premium Ropes recommends 50 diameters for a brummel. but yeah, it's more than you'd think. tapers get really important if you want that line to fit through whatever it's supposed to fit through.

 

[gkny]

I have seen the recommended amount of bury but I don’t need the full strength of the line. I upsized out of concern about chafe. Just wondered if there was any testing that had been done with shorter buries. The strops will have eyes on each end and I am trying to keep them relatively short

 

[CaptainAhab]

I have seen the recommended amount of bury but I don’t need the full strength of the line. I upsized out of concern about chafe. Just wondered if there was any testing that had been done with shorter buries. The strops will have eyes on each end and I am trying to keep them relatively short

The Youtuber I posted above has done real destructive testing on bury length of dyneema eye splices short, long, tapered properly, bad tapers, etc. Look through his other vids.

 

[SloopJonB]

Brion Toss's recommendation was 72 diameters. Premium Ropes recommends 50 diameters for a brummel. but yeah, it's more than you'd think. tapers get really important if you want that line to fit through whatever it's supposed to fit through.

I'm glad I went with halyard knots - the line strength for line big enough to handle is so far beyond anything I need that a big percentage loss is meaningless.

Plus they won't jam in skinny sheaves.

 

[LewSipfher]

My real world experience for 20 years now is that 72 diameters and long taper has not failed. Where my stuff has broken has to do with chafe and UV/age.

I am coming to the conclusion that maintenance should include recoating with something every five years. Hell, even latex exterior paint would help

 

[CaptainAhab]

Sampson specs 3 fid lengths. I checked the tables. It's a 66:1 bury. 1 fid tapered + 2 fids.