Forums: Climbing Information: The Lab: Re: [adatesman] SAFETY ALERT- MORE ALIEN FAILURES: Edit Log




jsj42


May 20, 2009, 6:25 PM

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Registered: Dec 24, 2002
Posts: 374

Re: [adatesman] SAFETY ALERT- MORE ALIEN FAILURES
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Well... I'm not so sure I think this is as big a deal as you're making it out to be (on this site and pn Mountain Project). Here's why:

First, the Red Alien. This piece was bootied, and when you tested it, the head was tweaked and several of the strands of the cable were already broken (from what I could see on the photo you posted, it is actually a sizable portion of the cable that is broken). Obviously this piece held a whipper. In my experience, body weight can tweak a head, but only a whipper will tweak the head and break cable like that. Even if it wasn't a whipper, this cam was certainly abused.

Any climber knows that you should visually inspect your gear. If you have a core shot rope, a worn out belay loop, or a fucked up cam, you're NOT going to climb on it! One look at that red Alien would have kept me from climbing on it (and obviously it kept Tigerlily from even wanting to keep it).

I would have no reason whatsoever to believe that this cam would be full-strength prior to testing. Sorry to rain on your parade, but not even the "failure mode" of the cable pulling apart from the braze bothers me. If cables are broken, who knows how the braze had been affected and exactly where else it had been weakened by whatever forces tweaked the cam to begin with. Those are unknowns. Sorry, but you need to be testing NEW Aliens if you want to prove anything. In my opinion, the moment a cam is placed for the first time, the countdown on it's lifespan has begun.

Regarding the Purple Alien. You could certainly make more of a case here. Even though 11 kN is a damn-safe number by free-climbing standards, it is lower than the minimum failure rating for the cam. However, the cam is still a used cam. Has anyone ever hung from it? Has it held falls? Perhaps it was tested by CCH, but if their testing setup works by testing the cable and the braze, that would leave the loop, the cam lobes, and the axle as possible failure points that aren't accounted for. That's a problem. But how exactly did it fail? Is it possible that the wear on the cam lobes caused them to slip or be loaded asymmetrically, which could, in turn, cause the axle to bend? I don't know, I'm not an engineer and I wasn't there.

I'm not trying to defend CCH -- I think they've got a lot of problems. But as far as I can tell, you can't go making conclusions based on two isolated tests of used (and in one case obviously damaged) pieces.

(This post was edited by jsj42 on May 20, 2009, 6:28 PM)



Edit Log:
Post edited by jsj42 () on May 20, 2009, 6:28 PM


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