Had some splices tested!

Well I respect your opinions, experiments and thoughts but I still stand by my decision/thought to use the locking brummel. We're going to have opposing viewpoints and different reasons why so theres no use fighting over whose going to win. This kind of leads me into my next thought that I've seen around about locking stitch vs whipping. I need to find the article where I read this but a study was done on lock stitching vs whipping and it showed that the actual stitching compromised the strands in the rope forcing it to have a premature break. In short, splices that were lock stitched broke sooner or with less force than those with just whipping. I dont know what your thoughts are on this, if youve seen the same thing or have played with it yet but so far, I've just been whipping my splices and doing nothing to my double braid splices. What does everyone else think?
 
Lock Stitching

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...it showed that the actual stitching compromised the strands in the rope

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Absolutely. Any disturbance to the natural lay of the rope is going to weaken it.

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...forcing it to have a premature break.

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Think about it. You place the stitching at the throat of the splice where you essentially have 2 full ropes (cover and bury). Those two ropes together are way stronger than just one rope. Now you weaken the double rope a bit by placing some stitching. It is still way stronger than a single rope. The proof is that the spliced rope never breaks in the spliced section, and certainly never breaks near the throat, stitching or not. It breaks at the end of the bury, a long ways away from any stitching. There are good mechanical reasons to expect that to be the weak spot, and experiments show that it is.
 
Re: Lock Stitching

Okay, well now my question is, is it really worth lock stitching if its going to take strength away, whether its a lot or a little who knows. On an HRC or Beeline splice like mine in the tests it needs to be whipped or stitched to keep the cover in the correct spot and from slacking in the middle where you'll be tieing a hitch. But on a double braid rope, would stitching really do anything? its going to weaken it like we both agreed.

So, whip or stitch covers on to brummels or eye and eye hitch cords and dont stitch double braids?
 
Stitching or Whipping

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...its going to weaken it like we both agreed

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Why would you care, since the splice doesn't break but the rope does, at the end of the bury? A small amount of weakening of the strongest part of the eye-splice assembly doesn't change the overall strength at all. There is no penalty whatsoever to using stitching.

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...But on a double braid rope, would stitching really do anything?

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I'm not sure. A DB splice that is even a little bit loose could probably work its way apart. I put stitching in any splice I plan to hang from, but a DB splice in, say, Blaze, is so tight I find it hard to imagine it could ever work apart. Also, I have done a lot of experiments with stitching in hollow braid, so I know what it does and I know that it is needed. I have done no similar experiments with DB, so I cautiously stick with the manufacturer's instructions.

In a hollow-braid splice, incidentally, the manufacturers specify stitching, not whipping. I have done enough testing of stitching and whipping to convince myself that the manufacturers have this one exactly right, but it is a rather long and complicated discussion. It would be rash to simply assume that whipping is equivalent to stitching. The prudent thing, unless you know better, is to follow manufacturer instructions. Their recommendations may be overly conservative in some instances, but you won't know this unless you have done some engineering of your own. And besides, it is a lot easier and less bulky to apply a few stitches than to create an equivalently effective whipping.
 
Re: Stitching or Whipping

So to keep this thread going, has anyone been testing their splices too? if so, what kind of splice, rope, whats it going to be used for and what have your test results been?
 
Hello,
In defense of the LB, note that testing machines bring the load up at a set rate, typically with precisely calibrated pauses. This is nothing like field usage, where shock loads, cyclic loads, bends over random radii, and assorted odd interactions are the rule. Given the astonishing slickness/strength of HM fibers, insurance is a good idea. LB's are insurance.
Granted, assiduous stitching will reliably keep splices from slipping, but I have seen stitching fail, either because it was chafed or UV'd away, or because it simply wasn't strong enough to stop slippage to begin with. So if you aren't going to Brummel your splices, I recommend a lot of stitching, taking care not to distort, and thus weaken the splice. One of these days, maybe, I'll stop using Brummels. Meanwhile, they are a reassuring presence.
Fair leads,
Brion Toss
 
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... Meanwhile, they are a reassuring presence...

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I think you have hit the nail on the head. My arborist friend down the road, who has 35 years' experience climbing in trees, is "reassured" when he hooks into the 12,000-lb. steel shackle on his belt instead of one of my little 5000-lb. aluminum carabiners. So be it. But the question is: is he actually safer? Does the locked Brummel backing up a full-length-bury splice make one safer? Reassured, yes, safer, I doubt it. When someone presents me with convincing evidence that a simple bury splice made with the manufacturer-specified bury length has actually pulled apart I will also start to back up such splices with LB's.

I have the advantage of having my own testing rig so I can see for myself how extremely conservative the official specs are (as they should be), even in the case of the slippery hi-tech fibers. People will do what makes them feel secure, even when there is no rational basis for what they do (I am no exception). I just want to bring the facts back into the discussion, which in this case are highly reassuring themselves, so that people will have more than mere emotion as a basis for their decisions.
 
Re: Lock Stitching

[ QUOTE ]
...it showed that the actual stitching comprom The proof is that the spliced rope never breaks in the spliced section, and certainly never breaks near the throat, stitching or not. It breaks at the end of the bury, a long ways away from any stitching. There are good mechanical reasons to expect that to be the weak spot, and experiments show that it is.

[/ QUOTE ]

No, no, no. Things don't always fail at the stress riser; load deformation "travels" to an area of lesser mass. Even crappy splices will usually break past the splice tail. For that matter, knots, which weaken the rope much more, don't break at the greatest point of bend -- inside the knot. The question, in either case, is: How much weaker is the rope? Or rather: Can I stitch the rope sufficiently to prevent slippage, without weakening it? Here I think we are in agreement, that careful stitching is better than whipping. But it requires skill, and time, and might have no advantage over a Brummel.
Note also that New England Ropes is now recommending extraordinary bury lengths for Endura 12 and T-900. When I spoke to them about this, they said it was insurance against insufficient -- or absent -- stitching. This HM stuff is slick.
As I said earlier, I will likely come around to the just stitching camp some day. But as long as an LB and bury work perfectly, there's not much motivation to change, you know?
Fair leads,
Brion Toss
 
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