A concern about the Arborist Splice

[RonReese]

Iím new to braided rope splicing, but I have done 6 eye splices in Velocity rope following Samson Ropeís instructions. They work and look good. After watching Brionís splicing video, I now know how to make them better ñ a special thanks to Brion for taking time to make a video on splicing.

Getting to my concern, I made my first eye splice in ArborMaster 1/2î rope. ArborMaster is a braided cover with a core of twisted strands. I watched Brion Tossís video where he spliced an eye in New Englandís Safety Blue rope. Safety Blue looks like it has the same or at least similar construction as ArborMaster.

To make a long story a little shorter, by the nature of the arborist splice, the core and the cover overlap inside the cover well down the rope away from the eye. Thatís what concerns me - the overlap. The overlap of the cover and core, inside the cover, seems to me, produces a weak spot in the rope. At the overlap, I presume part of the strength at the overlap is supposed to come from the overlapping core and cover strands and hence, presumably the overlapped strands have nearly the same strength as the non-spliced rope. At least thatís what weíve been told ñ a splice approaches the full strength of the rope.

But if the overlapped strands can slip at all, load is transferred to the cover. I suppose there is the Chinese finger trap action of the core at the overlap, but even with that if there is ìthinningî of the core due to a slightly insufficient overlap there will be a reduced cross sectional area and it seems like that would produce a significant reduction in strength.

Thoughts?????

Thanks,
Ron

[Brion Toss]

Hello,
Excellent question. On some ropes, like Sta-Set-X, all of the strength is in the core. An overlap splice in that rope would have some strength, but not enough; that's why the X splice is the way it is. But in arborist and similar ropes, most or all of the strength is in the cover, and the core is there to keep the rope round. The overlap is meant to maintain constant diameter, not to contribute to strength.
Note that some arborist rope, like Fly, has all the strength in the core, even though the construction looks the same as cover-strength ropes. So as with any splice, make absolutely sure you are doing the right splice, before you pick up your tools.
Fair leads,
Brion Toss

[RonReese]

Thanks, Brion. That's a relief. If the cover is the strength then my concern goes away.

Here's a link to three pics of the splice; you can't really tell much, except that its a splice.

Since I made the pics, I have stitched the base of the splice. I'm considering whipping it as well. I noticed your DVDs don't show a whipped or stitched splice, so I'm a litte foggy on what constitutes a good whip on this splice. Suggestions?

P.S.
How important and what is the purpose of stitching and whipping eye splices? Also, which is better, stitching or whipping?

Thanks,
Ron

Splice pics (three) - Some pics of Velocity splices as well (among other things):
http://www.combatcarry.com/vbulletin...ad.php?t=16495

[Brion Toss]

Hi again,
I mention elsewhere in the video that I much prefer stitching ó and invisibly stitching, at that ó to whipping. The purppose of both is to hold the splice together at low loads, when the "Chinese handcuff" effect is weakest. Whippings look emphatic, but they typically engage the interior of the rope minimally. This leaves the support largely to compression from the round turns. This seems less effective, as well as being vulnerable to chafe.
Because the cover is braided, stitching between surface yarns will always engage the layer underneath. So you can stitch invisibly, but still tie the core to the cover, with no chafe vulnerability. Plus I think it's more elegant.
Fair leads,
Brion Toss

[RonReese]

Thanks again, Brion. That's the way I see it as well.

I don't see any way to do a PM (private message), but I want to say this, so I'll take a bit of liberty to say it here:

I've been teaching at a community college for almost 20 years. I know good and bad "teachers" almost as soon as I see them in action. One of the things that good teachers do is break down complex problems to a logical sequence of less complicated steps. Another thing is they have insight to the "student's" perspective and knowledge base and work from that level. Good teachers have a way of gaining students' confidence and projecting the idea that "they" can do what their being taught. Probably most important of all is the hard-to-define talent of transferring knowledge. I believe this is one of the main things that separates excellent teachers from good teachers.

You exhibit all these things, and more. You clearly are a gifted instructor. I also enjoy those subtle humorous comments you make during the presentations, one for example, describing the enlarging of the core diameter from burying the cover/core inside the cover - "...it gets shorter and fatter, like we all do....". I could go on but, suffice it to say, WELL DONE!

[NickfromWI]

Originally Posted by Brion Toss

Hi again,
I mention elsewhere in the video that I much prefer stitching ó and invisibly stitching, at that ó to whipping. The purppose of both is to hold the splice together at low loads, when the "Chinese handcuff" effect is weakest. ...

What should we consider "low loads?" I like to pull on the eye of a non stitched single braid rope at various angles to see how quickly the handcuff action starts. What we do know is that the grabbing on doesn't happen immediately, and an arborist splice on the end of a climbing line is constantly being loaded and unloaded. Many times a day it sees those "low loads." Stitching or whipping is ESSENTIAL here.

We need to come up with a term for that "chinese handcuff" effect.

love
nick

[RonReese]

Nick,

Just so there's no misunderstanding, I'm not implying that stitching or whipping are not essential. I just want to be sure that the strength of the splice (not the security of the splice) does not depend on stitching.

I would be horrified to think that the support of my weight ( or more) would be dependent on how well and with what material an eye splice was stitched.

I have tested an unstitched, unwhipped eye splice in Velocity rope at 600# and it didn't budge even a fraction of an inch under repeated loading and release.

What I hope is true is that the strength of a splice is in the splice per se, not the splice plus stitching. I'm hoping that the stitching is there just to keep the splice from being inadvertantly pulled or worked loose at no or low loads.

Ron