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rgold
Trad climber
Poughkeepsie, NY
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May 27, 2010 - 12:26pm PT
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With regard to the newer no-double-back aka speed-adjust harnesses, I've wondered: do you suppose there is any real chance that you could catch the buckle on a nubbin in a squeeze and loosen the belt while you're climbing?
Someone mentioned this, I think in the comments on the SuperTopo harness review.
I think we spend a lot of time (not necessarily unwisely) guarding against very low-probability events, and this type of loosening would certainly qualify as low-probability. Since we don't actually have any real knowledge of the probabilities involved (and few if any of us have any idea how we would adjust our behavior even in the presence of somehow known probabilities), it pretty much comes down to how much this worries us.
I don't do enough offwidth to be even remotely concerned, although I could imagine, on days of high nameless dread, putting a stopper half-hitch around that buckle before starting up a terrifying squeeze. On the other hand, if the Wide was my everyday cup of tea, I could see going for a double-back buckle, which I dislike, primarily for their inconvenience when adjusting clothing.
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Jay Wood
Trad climber
Fairfax, CA
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May 27, 2010 - 12:38pm PT
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Coz says: (re bartack strength)
"There is no speculation, it's just is a fact. It's such a basic thing, you don't need data."
Does this belong on the religion thread?
A couple of other points:
-Petzel belay loops have only 3 bartacks
 Where is the matching concern (hysteria?) for other links in the anchor chain- sling, cam sling, etc.- all theoretically weaker than the belay loop?
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rgold
Trad climber
Poughkeepsie, NY
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May 27, 2010 - 01:52pm PT
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The claim that bartacking through all three sections is self-evidently stronger than bartacking through two sections is not self-evident to me. One reason why is that I've heard and read many times that bartacked runners, when tested, almost always break somewhere else---in other words, the tacked section is already stronger than the runner material. If this is true for belay loops, then tacking through more layers won't make any difference at all, since you'd just be reinforcing a section that isn't where the break will happen.
But the real issue isn't whether or not bartacking through all three layers is stronger. The issue is whether whatever extra strength obtained, if any, means anything in terms of the performance of the harness.
In this regard, the BD loops, with their two-layer tacking, are rated at 15 kN, as they have to be for certification. For most modern climbing ropes, that is about 70% higher than the load you could get by holding a factor-2 fall directly on the harness with no rope slippage. (Lotsa luck with that, sparky.) You just can't break such a loop in good condition, and still couldn't break it after it lost about 60% of its rated strength. (There is, by the way, a good probability that the actual strength of the loop exceeds the rated strength.)
And short of the factor-two scenario, the belay loop is probably rarely subjected to more than 4 kN at most; even that corresponds to a pretty burly catch. We regularly expect the single-layer bartacked loop on our cams to take potentially greater loads than the harness belay loop.
I'm sorry if this sounds disrespectful, but the only thing we learned from the Todd Skinner tragedy, which now must be mentioned every time someone worries about the strength of their belay loop, is that even the most bomber gear can break if it is determinedly misused. That accident has nothing to tell us about bartacks through two or three layers. I'm not sure anyone besides the rangers know whether the bartacks on that belay loop failed or whether, as I think likely, it broke in another spot, in which case its already overwhelming irrelevance to the present discussion would only be increased.
I guess I now have to mention that I'm not a user of BD harnesses and have no association of any kind with BD. It is the small details in harnesses that provide the only real choice criteria. I have yet to hear anything that would even remotely suggest to me that belay loop construction is an issue.
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healyje
Trad climber
Portland, Oregon
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May 28, 2010 - 10:25pm PT
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How about a Camp Thong...
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rgold
Trad climber
Poughkeepsie, NY
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May 29, 2010 - 09:34pm PT
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Sorry to rise to the Bait here, but I wouldn't worry for even a second. He's passionately concerned about the safety of his clients. Let's get a grip here; the ability to speculate about engineering choices on the internet has nothing to do with climbing or guiding competence.
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Steve Grossman
Trad climber
Seattle, WA
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May 30, 2010 - 04:35pm PT
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John- Unless you are heading into a striptease squeeze, pick up a Wild Things Wall harness for all day comfort and burly construction. I love mine for general use outings and walls. I would lose the legloop buckles for excess slot work and sew in 1" flat butterfly sliders.
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Mighty Hiker
climber
Vancouver, B.C.
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May 30, 2010 - 06:47pm PT
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Hmmmm. In the last month, I've climbed with someone who still just uses a swami (tied from 2" tubular), and someone else who uses a swami plus legloops. Admittedly neither climbs a great deal, and hasn't for some years, but still...
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deuce4
climber
Hobart, Australia
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Topic Author's Reply - Jun 5, 2010 - 04:31pm PT
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wow, lots of responses (and classic supertopo controversy)!
Thanks for all the input (and thanks Werner for the flattering words).
I went with the Misty Mountain Turbo Harness with a "Quick Adjust" buckle. Looks super nice. What great folks there, same as it was in the old days: could talk to the people on the factory floor, fast service, high quality. Incredibly refreshing for this old dad and former threadworker to see in the present "Climbing Industry"!
Really there's no question: good quality climbing gear made in the USA by climbers.
Thanks Mike and Goose!
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