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healyje
Trad climber
Portland, Oregon
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Aug 24, 2006 - 03:40am PT
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Peter,
If Hans or you can get a good closeup shot of the side profile of one of the outside cam lobes from the cam in question (shooting directly down and inline with the center of the axle) I have access to software that will input the photograph and analyze the location of the axle hole to determine and measure any deviation from the design location. Send me an email if you'd care to have this cam checked for a misaligned axle hole. If it is not a misaligned axle then it would, for whatever reason, likely have had to have been a bad placement.
Joseph
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Clint Cummins
Trad climber
SF Bay area, CA
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Aug 24, 2006 - 04:42am PT
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Peter,
Sorry to hear Hans got hurt - very sobering.
Because the Alien cams are all triggered to a single sheath, they do not expand independently. As a result, sometimes not all 4 cams will be touching the rock. This has been noted in the past (by Christopher Barrington-Leigh, I recall), and his observation was that you can work around this to some extent by *pushing* on the control bar after the cam is in place. This can help some of the cams expand if they were restricted by the single sheath. I doubt many people do this on a regular basi, and it is a step not needed with other types of cams.
If the Alien had seen a fair amount of use, there could conceivably be some dirt or some scratched metal between the cams which could also prevent the cams from expanding properly.
If the placement is deep like it appears to have been in this case, the problem would be hard to detect. Heck, it would be hard to detect unless the crack is horizontal and fairly shallow.
My own choice is to skip Aliens and use cams which are independently triggered. Perhaps best would be a Metolius 4CU in this size (although I use TCUs myself). I will admit I own one (blue) Alien, but I only use it for aid climbing. If I climbed in the Gunks I might use them.
Did Hans have a second cam in? No doubt this is ancient advice, but I always place two pieces of pro if there are hard moves right away. A single cam pulling has killed people before, like on Spiderline (JTree) within the past year.
Also, I agree the ability to edit the thread title would be a helpful upgrade for supertopo.com.
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elcapfool
Big Wall climber
hiding in plain sight
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Aug 24, 2006 - 08:43am PT
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I've been out of the loop for a while, so forgive me if my info is dated.
Are they still using the softer AL for the lobes? It provides better bite for marginal aid placements. For this reason, I don't use Aliens for freeclimbing.
Glad your buddy didn't get hurt worse, actually it's good timing, just enough time to heal before ski season.
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hardman
Trad climber
love the eastern sierras
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Aug 24, 2006 - 08:51am PT
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Happie
hang ten placement is not the greatest. i think the best cam for that climb is a grey alien anything else is crap
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Maysho
climber
Truckee, CA
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Topic Author's Reply - Aug 24, 2006 - 09:37am PT
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Joseph, thanks for the offer! I will follow up with Hans and get that photo.
Yep, two cams in that spot is the ticket. It was my first time watching someone lead the crack, much less belaying it, so I did not know the deal, or where the low crux was etc. Others who were there, stated that they had used two pieces at that spot. Hans had sent the crack twice on toprope and had tried to lead it before, so he knew what he wanted for pro. I am usually the one to dispense unsolicited safety advice, I regret that I did not do so then.
Good reminder for us all to speak up when it looks funky. I also think a grey camalot would work fine in nearly the same place and be stronger.
I really appreciate the good info contributed,
Peter
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bobmarley
Trad climber
auburn, california
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Aug 24, 2006 - 12:36pm PT
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peter no way man?! i can't believe it pulled (or failed). glad hansy is not too badly injured. bummer man. please pass on to hans that i said 'yo'. i don't think he gets online much. see you up at 'the office' soon.
-patrick
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andanother
climber
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Aug 24, 2006 - 12:58pm PT
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While I’m not a big fan of CCH, I think it’s pretty lame to say the cam “failed”. Aliens have been subject to plenty of legitimate failures over the years, but this isn’t one of them. If there was no damage to the unit, then you can’t blame it on the cam.
You didn’t mention what brand of shoes he was wearing. Perhaps it was the rubber on the shoe that “failed”.
Or what brand of chalk does he climb with? It sounds like that brand of chalk “failed” and should be held responsible for this accident.
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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Aug 24, 2006 - 01:05pm PT
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Since the brand name Alien was mentioned in the title of the thread, here's a counterpoint:
At Lover's Leap, I got a good placement with a single *blue* Alien in the roof-crack of East Corner,
and then took 3 consecutive falls on on it before sheepishly french-freeing the move
(in full view of loudly heckling spectators ("friends") on the Pony Express Trail).
The follower removed the Alien effortlessly.
Again at Lover's Leap, a friend fell low on Roofer Madness and blew a well-placed
yellow Camalot low on the route and decked, landing on his feet with no injuries.
An experienced climber, he had no idea why it blew.
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JuanDeFuca
Big Wall climber
Stoney Point
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Aug 24, 2006 - 02:05pm PT
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I wonder what the force over time looks like for a cam in a fall. Vibrations may cause it to walk out.
I doubt anyone has ever done any experiments.
What could be revealing is high speed video of cams with different loading rates.
Did the leader grab the rope?
Juan
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healyje
Trad climber
Portland, Oregon
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Aug 24, 2006 - 03:02pm PT
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It would also be interesting to know if the cam was slinged at all and whether it had rotated up to the horizontal as Hans went by it. Sometimes during a fall, when a cam has to rotate back to a more or less vertical orientation to start loading, the process of rotating down puts all the cams in motion relative to the rock and they just keep moving rather than re-catching on to the rock. I don't like having my cams rotate up this way for this reason though this failure modality is more common in smooth, slick rock and in parallel-sided cracks.
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Lambone
Ice climber
Ashland, Or
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Aug 24, 2006 - 03:28pm PT
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This is why it is smart to use TWO pieces if your looking at a ground fall. Especially on a 13a, sheesh!
Cams pull, I have had a Red Alien pull out of a perfect pinscar placement after standing on it for 2 minutes (Tangerine Trip). No explination...shit happens.
I also had a #4 Camalot blow on me on the Captain, so it is not a brand specific issue. It is user error or bad luck.
But we as Americans must continue to search for someone to blame other then ourselves.
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JuanDeFuca
Big Wall climber
Stoney Point
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Aug 24, 2006 - 05:01pm PT
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Its all about Karma.
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G_Gnome
Social climber
Tendonitis City
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Aug 24, 2006 - 05:11pm PT
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Juan, karma is spelled with a small 'k'. Only Werner's is spelled with a big 'K' cause he has so much built up.
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Burns
Trad climber
Arlington, VA
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Aug 24, 2006 - 05:43pm PT
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Clint-
I would generally disagree with your 'single trigger' assessment of aliens. All cams have a 'single trigger', although some cams, like camalots, have enough 'wiggle' in the trigger that the lobes are able to move generally independently. Metolius cams, because their triggers are fixed to the U-stem and can't 'wiggle' the same way a camalot's can, are probably the worst in the sense of operating with the 'single trigger' effect you are talking about. But all cams tend to overcome this to some extent with independent springs for each cam lobe. Aliens have internal springs that will operate each lobe independently. I've put my aliens in many funky placements and haven't ever seen a case where one of the lobes was not touching the rock because of this 'single trigger' effect.
As far as walking, aliens tend to be better than most cams because the stems are so flexible, the flexing of the cam can't really activate the trigger, and the slings attached to them are a little longer than most cams. Thats not to say that walking couldn't be a part of the problem, especially if the climber climbed up, back down, and back up again.
The other thing that I thought of is that you mentioned it was a slightly constricting spot (I assume you mean constricting as in it would look like a good stopper placement?). Is it possible that the climber bumped the bottom of the cam up with his foot and pushed the cam into a wider or wierder part of the crack?
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Clint Cummins
Trad climber
SF Bay area, CA
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Aug 25, 2006 - 01:38am PT
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Burns wrote:
> I would generally disagree with your 'single trigger' assessment of aliens. All cams have a 'single trigger', although some cams, like camalots, have enough 'wiggle' in the trigger that the lobes are able to move generally independently. Metolius cams, because their triggers are fixed to the U-stem and can't 'wiggle' the same way a camalot's can, are probably the worst in the sense of operating with the 'single trigger' effect you are talking about. But all cams tend to overcome this to some extent with independent springs for each cam lobe. Aliens have internal springs that will operate each lobe independently. I've put my aliens in many funky placements and haven't ever seen a case where one of the lobes was not touching the rock because of this 'single trigger' effect.
Some good points here. I don't agree with everything you said here, but I do agree that all cams have some capacity to expand independently. It depends on the "degrees of freedom" in the way that the trigger bar, connecting cables, and springs operate. So really the important question is: "are they independent *enough*?"
I looked at a Metolius 4CU and a blue Alien, and pinched one set of cams tight with my fingers, to see how much the other set could expand. Actually the Metolius expanded quite independently, even though the trigger bar stays at a right angle to the stems. This is because the long/thin cables which connect to the stiff trigger wires will bend to allow the trigger bar to move up. The blue Alien does not have exactly the same mechanism, because its cables are so short that they cannot bend very much. But the cam pairs can expand independently if the cables of the tight cams are pushed through the flange. This is probably getting confusing, so in case anyone is interested, I made a small page with photos and explanations:
http://www.stanford.edu/~clint/alien/exp.htm
Here is one of the photos (to promote clicking on the above link):
These photos are OK for illustrating what I was talking about in my previous post. But I actually think they are pretty trivial and irrelevant to the safety of Aliens and Hans' accident. The main reason is that the independent expansion does not matter if the crack is sufficiently parallel. Also, the cam pair expansion in the blue Alien looks *independent enough* (to me), even without pushing on the trigger bar. Finally, if the crack is non-parallel, and one pair of cams has not been able to expand enough to span the local crack width, the unit will rotate radically if you test it by rotating the stem. This should be a "dead giveaway" that only 2 cams are touching the rock and the placement is bad. In the marginal situation where one cam pair is tightly compressed, and the other pair is almost fully expanded (i.e. ready to fail), you should be looking in at the cams and visually inspecting them anyway. So again, the default amount of independent expansion doesn't really matter, since you are inspecting it anyway.
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Minerals
Social climber
The Deli
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Aug 25, 2006 - 01:45am PT
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Hey, cool gear-geek talk here. Hope Hans is doing well – good luck on a speedy recovery, dude!
Mark and I walked up to Star Wall to have a look today, after adventuring on the mere mortal crags below. The cam slot in question is obvious from the base of the wall – dreamy to any aid climber venturing up the Leaning Tower (or at least is seemed like it from our perspective…). A red (or possibly gray) Alien was my first thought, but what does that matter from someone who requires aiders to climb such a route? Anyways, weird things happen and climbing is definitely weird. I love Aliens and always will. Schist, I paid retail… (RETAIL???) for 4 new ones today…! Damn, they must be good! I’ve popped the odd placement a couple of times while testing, but overall, Aliens have always held when it counted. They rule.
As for the rock type on this route, yes, it’s a little bit different than most of the crags in the area. I’m no expert on the area (…you seen any fixed heads around up there…?) but from the quick hike this afternoon, and a few looks here and there, it seems that the main granitic unit in the Donner Pass area is a slightly porphyritic granodiorite. Porphyritic refers to larger crystals contained in a finer-grained crystal matrix; these larger crystals are just small versions of the large phenocrysts and megacrysts that we climb on in Tuolumne – large potassium feldspar crystals. I also noticed another granitic unit that is slightly darker in color and has a greater percentage of dark (mafic) minerals and lacks the larger feldspar phenocrysts. If compared to Yosemite units (in the sense of an intrusive suite), these two units roughly equate to Half Dome granodiorite (younger, lighter in color, porphyritic near Tenaya Lake) and the tonalite/granodiorite of Kuna Crest (older, darker in color, rockfalls above Glacier Point).
Anyways, (blah, blah, blah…) the area around the crack is composed of a hybridized mixture of granodiorite and a localized mafic/basaltic intrusion. A mafic enclave swarm (a la Killer Pillar, Knobby Wall, etc.) can be seen in the upper two-thirds of the route, on the right side of the crack (although ‘erosion’ has sheared off the face of the cliff, rather than shape the enclaves into nice handholds and footholds, as listed above). The enclaves are surrounded by a hybridized diorite, the result of mixing between mafic dikes/intrusions and the slightly older granodioritic host rock (a la North America diorite intruding El Cap granite on the Big Stone).
So, with all of that jargon said, although the rock is of slightly lesser ‘quality’ (i.e. NA diorite) than our standard “granite” it is still pretty darn bomb squad and I would not attribute any gear failure to rock quality (or lack thereof). The surface of the rock seemed quite solid to me… now I just need to convince ‘em that it’s ok to place heads and beaks up there… Heh…
Aliens still kick ass!!!
Heal quick, Hans!
(ps – Hey Peter… way cool to see you posting on the Taco these days! Keep up the old school spirit!!!!!)
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NeverSurfaced
Trad climber
Someplace F*#ked!
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Aug 25, 2006 - 12:35pm PT
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But we as Americans must continue to search for someone to blame other then ourselves.
he he he...
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Burns
Trad climber
Arlington, VA
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Aug 25, 2006 - 01:47pm PT
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Clint-
You're right about the independence of the metolius cam lobes (pic and link weren't working for me so I didn't see your pics, but I followed what you were saying). I had forgotten that the trigger wires were fairly soft. I don't use mine that often (I prefer aliens...) The big thing about those u-stem cams is the stiffness of the U-stem in the direction that would cause the cam to walk. You can take the thumb loop of an alien and touch it to the head. In a bomber placement, you can wiggle the thumb loop all over the place and the head won't move a bit. Doesn't work that way with most other cams. That, and the fact that you can put a 90 degree bend in the stem and still operate the trigger as normal to set the alien just so in funky placements, is what makes the trigger sheath design so brilliant. Combine that with internal springs for narrow heads, and you've got one of the most brilliantly simple designs in climbing.
Is any of this particularly pertinent to the accident? Probably not. Here's what I envision happened with the alien. It was a yellow alien, so not that large. It sounds as if the crack got a little wider higher up, and from Mineral's assessment, it may have been a better placement higher up with a larger alien. Alien gets placed in a decent spot, climber passes it and either moves it with his feet, hands (did he put his fingers in the crack right under it? Yellow alien is primo fingerlock size...) or with the rope and rotate the head such that the outer two lobes moved up into the wider section of the crack. If the climb traversed a little, an alien, because of the flexible stem, pulled directly to the side can also be induced to rotate up, putting the outer part of the head higher into the wider crack. Add in a downclimb (and possibly a couple yanks on the rope to test the piece), and you've rotated the cam to the original orientation, but now farther up. Climb up one more time and you've got the cam a little higher. When the cam gets loaded in the fall, it will likely rotate a little more and either umbrella or just plain pop because it is now in a bad placement.
Of course, this is all just conjecture, but I'd be curious if someone went up there with a pair of aiders and got a photo of a yellow alien in the original position of the cam (look for track marks too). Seems like for my 'theory' to apply though, it would have to have a fairly significant upward flare to it or it would have to have been a marginal placement at the beginning.
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JuanDeFuca
Big Wall climber
Stoney Point
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Aug 25, 2006 - 01:49pm PT
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It seems a simple experiment to return to the crack, place the same gear on rappell. And experiment with torques to see what the hell happened.
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Karl Baba
Trad climber
Yosemite, Ca
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Aug 25, 2006 - 03:06pm PT
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It would be interested to see if there were any track marks in the crack.
I remember standing on a seemingly bomber placement under the roof of the second pitch of Zodiac for several minutes (we were taking picture) before it suddenly cut loose. I had done the pitch several times before and always wondered how folks managed to fall on it as much as I heard.
The potential of a misalligned cam lobe hole is certainly worth following up.
Peace
karl
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