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标题: QC Lab: How strong is the Spinner Leash? [打印本页]

作者: 撒手    时间: 2010-3-3 13:27
标题: QC Lab: How strong is the Spinner Leash?
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I don't usually write-up BD product specific tests and results, but I've just been getting so many of a similar type question on the Spinner Leash lately, that I felt I needed to. And to be honest, these questions are kinda freaking me out.

"I just bought the Spinner Leash, How strong is it?"
"Is the Spinner Leash strong enough for it to hold me if I get too
pumped?"
"Will the Spinner Leash hold a fall if I whip onto it?"
"I want to make my own ice climbing tether system, how strong do I need to
make it?"
"Is the BD Spinner Leash stronger than the Grivel Double Spring Leash?"

Why do these sort of questions freak me out?  Because it shouldn't matter how strong these things are.  Sure they're rated to 2kN—like most tethers—and you can hang on them if you wanted or needed to, but you must remember that the leash is only as good as the
placement of the ice tool it's attached to. Think of bounce testing a Pecker with a daisy chain. If the Pecker blows, you have it zinging towards you—same as if you decide to weight your tools via your Spinner Leash, except the tool is further out of your reach and has way more mass, and now it has the potential to slingshot towards your head. Ouch.
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Ultimately the real purpose of these leashes is to stop your tool from falling into oblivion should you drop it on a long ice or alpine route. They're not really designed as something that you should sit on if you get too pumped mid-pitch (they are too long, and then you will have to climb back up to the tools), and they're definitely not intended as a "just in case"
if you were to whip, or used as a personal anchor system at a belay. I could compare this potential misunderstanding of usage of a Spinner Leash similar to the common misunderstanding and mis-uses of a daisy chain. I've seen folks using daisy chains incorrectly when aid climbing (e.g., you should never use a daisy chain such that there is even a possibility of taking a fall directly ONTO it).  And I've seen tons of folks at the cliffs
using daisy chains as personal anchor systems—do you know the pocket strength on most daisy chains is ~ 500 lbs, a load easily generated with a slip, small fall and jolt onto the anchor? Daisy chains aren't designed for that kind of loading scenario—and neither are Spinner Leashes.

Bottom Line

The Spinner Leash and most new-school leash/tethering systems are intended to stop your tool from falling, NOT intended to stop YOU from falling.

I apologize for the soap-box-type speak, but just wanted to spread the word about the tether systems and the fact that you shouldn't be anchoring into anything with them, whipping onto them, and strongly consider the risks of weighting them at all if you are pumped.  

Be safe out there.
作者: 撒手    时间: 2010-3-3 13:35
本帖最后由 撒手 于 2010-3-3 13:40 编辑

原文地址
http://www.blackdiamondequipment ... s-the-spinner-leash

有些地方没看懂,不过大概意思是说,这种Spinner Leash(攀冰时用来挂冰镐的绳子),绝对不能承重,只是防止轻量级的装备掉落的,需要挂大包或者挂人的时候用菊绳(daisy chains)。
攀冰的时候,如果感觉到快力竭,应把冰镐取下来,让绳子承受体重,如果镐取不下来,当身体把这根绳子拉到一定程度,可能把镐拉掉,会砸到脑袋上,鲜血四溅。

不要让你完全力竭,我觉得他是说的这意思。
作者: 逛山    时间: 2010-3-3 14:07
图片画的太惨烈了!所以脐带的放置很有讲究,先锋一般不用脐带,顶绳的时候脐带是用锁扣在主绳上的!目的就是为了防止脱离和脱离的时候脐带受力拉下冰镐伤人。
杀手第一次发我么见过的技术性文章,赞一个。
作者: 紫格.xixi    时间: 2010-3-3 14:49
想起来后怕,要是上次冰镐掉下来砸我脑袋上就彻底交待了,理论知识还是非常重要的,顶一个
作者: 镜子    时间: 2010-3-3 23:10
杀手进步了。。。
作者: 雪地狂奔    时间: 2010-3-4 09:27
杀手继续!




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