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cracklover
Jan 9, 2013, 6:31 PM
Post #26 of 33
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camhead wrote: The rock in the video is volcanic; columnar ryolite, I believe. We can armchair critique this all we want, but the lesson that most people should take from this is that parallel splitter cracks in very hard rock can have worse cam placements than in similar cracks of sandstone or granite. The hardness and smoothness of the rock basically makes it difficult for cams to grip into it. As granitegrl said, limestone can be really bad for this, too, but limestone also tends to have more bottlenecks and constrictions in it, which of course will make both cam and nut placements in slick rock much better. I've not climbed at Frog Buttress, but there are a couple places in the US that are also smooth, columnar igneous rock (Frenchman's Coulee and Paradise Forks); I recall stories from both areas about apparently perfect cam placements in parallel cracks simply pulling out. Bottom line: in rock like this, do not expect to rely on the same cam placements that you would get in an identical Yosemite or Indian Creek splitter. Flares and parallel cracks should be suspect; look for bottlenecks, stopper placements, etc.
Amen. And google Göran Kropp air guitar to learn about worst case scenarios with this. (Short version - many cams ripped out, resulting in death).
GO
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healyje
Jan 9, 2013, 6:58 PM
Post #27 of 33
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I'm a sandstone guy, but I've lived in the PNW climbing columnar basalt since '87 and am well familiar with the protection in it at places like Vantage. In my opinion there is lots of confusion here between competence, quality of placements, and the type of rock.
In this case at Frog Buttress and in Göran Kropp's case at Vantage, I very much question their level of competence for the task at hand in the rock type they were climbing.
Yeah, there are rock types where you have to be careful with your placements and preferably double-up and consider the slinging, but bottom line, when you rip or zipper a line of pro you alone, and your skill and judgment, are the root cause of the accident - not the rock.
(This post was edited by healyje on Jan 9, 2013, 7:00 PM)
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rgold
Jan 9, 2013, 7:08 PM
Post #28 of 33
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Cams work on friction. The tangent of the cam angle has to be less than the coefficient of friction in order for the cam to hold. When this condition is met, the cam should hold for any load (up until the cam structure itself is compromised), which means that jerking on the cam is, in theory, a reasonable test of holding ability.
In practice, not so much, since the rock surface can crumble and the cam lobes can deform, invalidating the elementary theory, but even so a solid jerk or two is a basic test of cam integrity, and according to at least one test I've read, jerking "sets" a cam and increases holding power.
So, in addition to doubling up on ground-fall protection (surely the most basic requirement for all trad leading), I'd say jerking on those cams would have been a good idea.
In view of the fact that the coefficient of friction has to be bigger than the tangent of the cam angle, slick rock might demand smaller camming angles, which suggests Metolius cams or, perhaps even better, Totem cams.
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camhead
Jan 9, 2013, 7:17 PM
Post #29 of 33
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healyje wrote: Yeah, there are rock types where you have to be careful with your placements and preferably double-up and consider the slinging, but bottom line, when you rip or zipper a line of pro you alone, and your skill and judgment, are the root cause of the accident - not the rock.
I'm not sure if you are trying to disagree with what I said or not, but we're essentially saying the same thing: climbers need the skill and judgement to know that harder, slicker rocks like columnar basalt do not always afford the same protection options that granite or sandstone do.
Also, I'm not a physics type, I'm not sure that simply "doubling up" on placements in parallel, non-constricted cracks is the end-all for slick basalt. Maybe equalizing two pieces would be, but I think that focusing on constrictions would be the first thing to shoot for on this type of rock.
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healyje
Jan 9, 2013, 7:40 PM
Post #30 of 33
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I'm saying Jim Donini has never torn a line of cams to my knowledge and that isn't a fluke or by chance - he simply knows what he's doing.
Doubling up on any placement with groundfall potential in any rock is a smart move - doubling up on cams at a placement does in fact increase your odds in the absence of any other mitigating factors whether the rock is slick limestone or creek splitters.
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patto
Jan 10, 2013, 9:49 AM
Post #31 of 33
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I have long had great preference for cams with a low camming angle. If you climb slick rock this mean avoiding BD and aliens in preference to WC, DMM, Metolius and Totem. Numerous debates and arguments on RC have concerned aliens.
Equalising is certainly not a solution to slick rock. Slick rock cause of cam placement failure is largely binary it either holds or fails. I'm also not particularly a fan of doubling up unless you have reason to be unsure about you first placement. Though naturally if it is a cruxy move with possible groundfall potential then I'll place as many pieces as would make me feel comfortable and safe!
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healyje
Jan 10, 2013, 12:21 PM
Post #32 of 33
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Again, having climbed at Vantage (Frenchmen's Coulee) and similar PNW rock I can assure you it's not that big a deal, nor do I suspect Frog Buttress is any more problematic than Indian Creek. I've also trad climbed on the limestone at Krabi/Railay and didn't find it warranted more than a bit more care than an Eldo or PNW basalt.
Double up at groundfall placements, do as everyone is sugggesting and look for surface irregularities and constrictions, if any placement is suspect then double it up as well.
(This post was edited by healyje on Jan 10, 2013, 1:07 PM)
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rightarmbad
Jan 10, 2013, 12:33 PM
Post #33 of 33
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Registered: Mar 22, 2005
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Actually, Aliens work extremely well on this route.
The soft lobes hold extremely well.
Frog in general has bomber rock with easy safe placements.
There are however some sections of rock that have a black slick outer layer with very little friction.
The big problem here on this route, is that to sight the details of the placement means getting yourself in a very unbalanced sketchy position, as you tend to climb left of the crack and just peek over at the crack to place.
There is no reason to not double up down low as the crack widens all the way to the top and those size cams are no longer required.
Myself, being somebody that has a bit of a reputation of being a little too run out sometimes as a climber, place some six or seven pieces befor the top of the pillar to his left.
I have been known to do routes there with only two pieces in thirty to fifty meter routes.
But not in circumstances like this where the crux is low and can not adequately be inspected.
This is pilot error pure and simple.
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