Originally Posted by DemostiX
There are several remarks about tapering the bury in this discussion.
Everything I find from the rope manufacturers and from the boating community says the tapers are essential if the rope / cord is not to be de-rated. I find some estimates of derating by as much as 50%. Contrary to the thought expressed in this thread that tapering is of the strands in the last 1/2 to 1", it refers to the pulling of half the strands, each strand at an additional increment from the end to form a smooth taper.
The reason for the de-rating is familiar to me from well-documented metallurgical failure in bicycle parts in anything from the frame tubes to crank arms: "Stress risers" are just what the rope engineers refer also refer to. (eg. To collapse a bicycle down or seat tube, drill a couple of holes in one to mount another water bottle. There will be stress risers, from which cracks will emanate at those holes.)
So, you want to avoid any sharp discontinuity such as where the bury ends, by tapering it I don't know what Amsteel and similar looks like when it fails, but I can guess that most of us are not carefully examining our cord and rope, the way the nautical, arborist, climbing, and rescue types do. The best policy is to make splices the way the pros do, even if we don't have the experience of seeing failures in the field from the many more exposures to failure in harbors and other places where there is a lot of rigging.
This Samson Rope video is pretty clear on the taper, by using serious rope.
. Go about 40% in to see that creation of a taper in the bury.
Yup, thats the proper way to perform an eyesplice according to Samson. Who has a legal team directing them to CYA in any way, shape matter or form they can. Liability and all that.
Check this one out...
I sent a question off the Samson asking why they show a locked brummel splice with the taper consisting of just cutting the end at an angle, while an eye splice being 3 fids with the taper being pulling half the strands 1 fid in.... The response had a couple points...
First was that the whoopie sling has the majority of its derate at the exit point for the adjustable eye bury, so any derate from the "lack of taper" (if you want to consider it that way) is a moot point and negligible.
Second was for legal reasons.
I think you'll find, at least I have, among folks who actually use the rope, the cutting of the end at an angle yields sufficient results with no great loss in strength, if any. I haven't seen a practical splice yet that will place a 50% derate on the rope. Don't get knot derate and splicing derate confused. Even Samsons suggestion of 40% on a whoopie sling is very generous. Ive found a 7/64 sling to retain the majority if the lines average strength. Same with Dynaglide. All using an angle cut for the taper.