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patto
Mar 28, 2006, 12:42 AM
Post #51 of 54
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Registered: Nov 15, 2005
Posts: 1453
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Ah well guys. I guess we have to just disagree then.
A few last points:
-Jim, I don't have a habit of opening the gates of my carabiners during a fall. I don't load them across and edge. Thus I am not concerned about the gate open strength. (the gate can't open anyway once the load is >2kN)
-Jim, no i don't place brassies, micro cams and cam hooks in anchors, i don't want to. If i ever had to I would damn right use a sliding-x. Climbing I have placed small RP's rated for only 2kN!
-tradklime, no I'm not clairvoyant. However when I place a nut >#5 in a narrowing wedge of solid rock. I will bet my life savings that the piece will fail ONLY when the cable snaps. You will struggle to make a climbing fall exert such force to snap the cable.
-vivalargo
"But kindly don't imply that using the cordelette unequal arm configuration is a viable practice simply because more of such rigs haven't so far failed."
I have never used lack of failure as proof of safety (others have tho).
"What is the logic in continuing to use a system that testing has show to be sketchy (in certain circumstances) when a better system has been provided?"
You are assuming that a better system has been provided. As I and others have accepting, a sliding-x arrangement is stronger but that doesn't mean safer. This has been repeated numerous times but you have ignored it.
I and others are happy to use the cordalette. Sure go ahead and use your anchor, i have no issues. But please don't insinuate that the cordalette is dangerous.
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jimdavis
Mar 28, 2006, 2:17 AM
Post #52 of 54
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Registered: May 1, 2003
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In reply to: -Jim, I don't have a habit of opening the gates of my carabiners during a fall. I don't load them across and edge. Thus I am not concerned about the gate open strength. (the gate can't open anyway once the load is >2kN) -Jim, no i don't place brassies, micro cams and cam hooks in anchors, i don't want to. If i ever had to I would damn right use a sliding-x. Climbing I have placed small RP's rated for only 2kN!
BD free nuts start around 4-6kn, metolius cams 00-2 or 3 are 6.6kn, blue and black aliens are under 10 (some times a lot less :lol:) , the list goes on (this is off the top of my head). All of this is free climbing gear, used frequently in anchors.
Have you ever heard of gate flutter? Biners can open themselves (via momentium) when suddenly loading.
Shit happens. Your argument that a cam rated to 16 kn, clipped with a biner rated to 24 kn, is a solid anchor, is comical. You don't know for 100% how strong the placement is, and you can not guarentee 100% that no biner used in an anchor will ever see cross loading or an open gate at any point. And is using a cordelette anchor, your essentially belaying off one placement at a time.
The probility of the placement failing might be very very low, the same is true with an open or crossloaded biner. But the possibility exists.
Because that possibility exists, and we are putting our lives on these anchors, it makes sence to engage in practices that offer us the best chance of the anchor remaining strong, and secure. The cordelette IS NOT the best way to do this, and this has been proven.
The only arguments against using the anchors JOHN has described (not half of the crazy ass rigs people have come up with) is that they may take a little more time to setup. I'd argue they're on the same learning curve as the cordelette setup your arguing for. Practice the setup, and it'll come quickly.
Other than that, all your arguing is that your an old dog that doesn't want to learn a new trick.
It really seems like the only thing that's gonna get some "old dogs" to come around is having a piece or two of their cordelette anchor get ripped out. Hopefully that won't be too late.
John, I really hoped you passed your data along to the AMGA and such, it'll be good to see this stuff get intigrated into their manual and courses.
Cheers,
Jim
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billl7
Mar 28, 2006, 3:20 AM
Post #53 of 54
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Registered: Oct 13, 2005
Posts: 1890
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In reply to: Have you ever heard of gate flutter? Biners can open themselves (via momentium) when suddenly loading. s--- happens.
In reply to: The probility of the placement failing might be very very low, the same is true with an open or crossloaded biner. But the possibility exists.
Bill L.
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papounet
Apr 13, 2006, 9:41 PM
Post #54 of 54
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Registered: May 28, 2003
Posts: 471
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In reply to: Ropes are tested with a factor 1.77 fall and given a maximum impact force rating. These are normally around 8kN. I wont go on, you should know this.
Ahaha you should go on as you obviously don't have a clue.
UIAA standard mandates that the maximum force on the climber side is less than 12g. It does this by ensuring tthat the force during the first fall in a specific setup (80kg mass, ff1.78, static belay,etc) is less than 12kn.
Indeed many ropes have figures around 8 to9kn. but is is for the climber side.
The redirection point sees 1.6 times this amount and the belayer side sees .6 times this amount.
Older ropes, zigzaging and other factors lessen the capability of the rope to absord the energy of the fall and lead to higher force.
slipage at the belay device, inertia moment of the belayer, and other factors complement the rope and contribute to lesser force.
I invite you to use the Petzl fall simulator to get a grasp of the forces involved
The statement you are referring to was made by Chris Harmston, at that time QA manager at BD.
But you should read all of his writing.
have a look at one of my previous posts at
http://www.rockclimbing.com/...ewtopic.php?p=827002
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