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FriendOfMonoPockets
Apr 26, 2010, 10:35 PM
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This is why we have belay tests
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boymeetsrock
Apr 26, 2010, 10:43 PM
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Rope grabbers: Do you really feel that you will be able to arrest your fall should the belayer loose control at the moment of fully weighting the rope?
It seems to me that all you are really getting is a physical cue that your belayer has control of the break. A cue that may or may not be correct in the end. Do you disagree? (I don't grab the rope, so I don't know.)
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hugepedro
Apr 26, 2010, 10:57 PM
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boymeetsrock wrote: Rope grabbers: Do you really feel that you will be able to arrest your fall should the belayer loose control at the moment of fully weighting the rope? It seems to me that all you are really getting is a physical cue that your belayer has control of the break. A cue that may or may not be correct in the end. Do you disagree? (I don't grab the rope, so I don't know.)
You're not arresting your fall, you're holding your own weight to prevent falling, and that is easy.
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jt512
Apr 26, 2010, 10:57 PM
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boymeetsrock wrote: Rope grabbers: Do you really feel that you will be able to arrest your fall should the belayer loose control at the moment of fully weighting the rope?
That's not why you grab the rope. You grab the rope and ease your weight onto it to make sure that your belayer has you on tension in the first place. Sure, if your belayer decides to suddenly drop you the second you let go, you're in trouble, but that's beside the point.
Jay
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majid_sabet
Apr 26, 2010, 11:02 PM
Post #55 of 87
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FriendOfMonoPockets wrote: This is why we have belay tests
belay test is so some n00b could have a $6.75/hr job at the gym but generally those test are meaningless.
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ClimbClimb
Apr 27, 2010, 1:09 AM
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jt512 wrote: Well, in my humble opinion, you did not "make a minor approximation." You made a major mistake, leading to mathematically impossible results. As I stated above, your approach can lead to "probabilities" exceeding 1, which are nonsensical. If you want to "do the full math for me," please do, although I think I actually did it for you in my previous post.
The funny thing is that we agree on the key point -- it is good to grab the rope.
I was trying to avoid paragraphs of unnecessary nerdiness. The full math in this case would analyze the approximation, etc. Briefly, the point you're missing is that the probability of belayer failing are actually small quantities. My approximation was to say that (1-ab) is close to 1. That's true when "b" is a very small quantity, say 0.01 or 0.001. And, as you observed, it is not true if the probability of belayer failing is large, like 0.62 (or 62%). The full math would also include a parameter for repeated falls, etc.
I am quite comfortable with this approximation being minor not because the *formula* is correct (it's not, that's why I mentioned I was making an approximation), but b.c. the result is correct for the likely set of input parameters.
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jt512
Apr 27, 2010, 1:54 AM
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ClimbClimb wrote: jt512 wrote: Well, in my humble opinion, you did not "make a minor approximation." You made a major mistake, leading to mathematically impossible results. As I stated above, your approach can lead to "probabilities" exceeding 1, which are nonsensical. If you want to "do the full math for me," please do, although I think I actually did it for you in my previous post. The funny thing is that we agree on the key point -- it is good to grab the rope. I was trying to avoid paragraphs of unnecessary nerdiness. The full math in this case would analyze the approximation, etc. Briefly, the point you're missing is that the probability of belayer failing are actually small quantities. My approximation was to say that (1-ab) is close to 1. That's true when "b" is a very small quantity, say 0.01 or 0.001. And, as you observed, it is not true if the probability of belayer failing is large, like 0.62 (or 62%). The full math would also include a parameter for repeated falls, etc. I am quite comfortable with this approximation being minor not because the *formula* is correct (it's not, that's why I mentioned I was making an approximation), but b.c. the result is correct for the likely set of input parameters.
Under the assumption that b is small, I like your approach, but I wish you had spelled out the assumption in your first post. Doing so would not have required "paragraphs of unnecessary nerdiness." In fact, you could have made it clear using just two more words. You wrote, "[Y]our risk of hitting the ground is 50% * b + 100% * b (making a minor approximation)." Had you instead written, "Assuming that b is small, your risk of hitting the ground is approximately 50% * b + 100% * b," your assumption and its validity would have been clear. Just two more words (and that's assuming we accept that "b" is actually a word)!
Jay
(This post was edited by jt512 on Apr 27, 2010, 4:43 AM)
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ClimbClimb
Apr 27, 2010, 2:09 AM
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jt512 wrote: [ Had you instead written "Assuming that b is small, your risk of hitting the ground is approximately 50% * b + 100% * b," your assumption and its validity would have been clear.
You're right, that's a good way of saying it.
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bill413
Apr 27, 2010, 2:39 AM
Post #59 of 87
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hugepedro wrote: jt512 wrote: So, finally, the rope grabbers are coming out of the closet. Uh-huh-huh. Uh-huh-huh. Uh-huh-huh. (Just for the record, I don't want to be included in the AARP club, even if I might qualify. Ruins my game with the honeys.)
Guess I'll identify also.
I find that it makes getting my feet in the right place for the lower easier. If I just sag onto the rope, I usually go down a few feet (rope stretch, after all) before I stop...if the belayer keeps lowering during that time, it can be hard to get into a stable position.
Of course, if I only climbed overhanging routes, this wouldn't be a problem.
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onceahardman
Apr 27, 2010, 4:43 PM
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jmeizis wrote: Geez man you made it sound like the building collapsed and 20 people died with the thread title. Glad the climbers ok, but this sounds like an unfortunately common occurence.
I was picturing a "Hinterstoisser Traverse" kind of thing, in which the sun-bleached bones of the gym-goers remain stranded on the gym wall...
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shockabuku
Apr 27, 2010, 5:14 PM
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jmeizis wrote: I think I've shown that the statement has at least a little to do with the thread. Your crags must have some really rich and nice first ascencionists because I have never climbed at a crag where it was acceptable to toprope through the anchors and many crags I've been to it's not acceptable to lower through the anchors. I'd be more worried about inspecting those quicklinks you're lowering off of than whether your belayer is going to drop you. Why the hell would you gumbies wear out the anchor equipment so someone has to replace it more frequently than they otherwise would if everyone rappeled?
At all the sport crags I've been to, if there aren't many people climbing there, then it doesn't really matter which you do, there just isn't enough wear and tear. If there are lots of people climbing there then taking the time to rap is somewhat discourteous.
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markc
Apr 27, 2010, 6:26 PM
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jt512 wrote: edge wrote: Even if your belayer is spot on belaying while you are leading, there is something about the pause during cleaning and lowering that can knock them off their game. That is well put. I was trying to analyze exactly why lowering after cleaning is "different," and couldn't quite do it. The bottom line is exactly what you said.
I was giving this some thought yesterday. In the case where you're initially leading, slapping in draws, and lowering, you're not transitioning from one system to the other. The belayer is clear in her duties the entire time.
When you're cleaning an anchor, you're transitioning between systems. At some point, you're directly connected to the bolts/anchor, and often untied from the belay system. I want to double-check before ever putting myself on a new system.
What I typically do isn't dissimilar. I tend to anchor in with 2' slings rather than draws. When I'm retied and my partner starts taking out the slack in the system, I move up until my weight is off my direct connection. I sit back on the rope (testing it) before cleaning my anchor.
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drivel
Apr 27, 2010, 11:58 PM
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jt512 wrote: .... Finally, any time you have the opportunity to take responsibility for your own safety in climbing, and you fail to do so, you just plain fail.
so why don't you just rap every time you clean the anchors?
jt512 wrote: P.S. How can you not feel at least a little bit stupid arguing against a safety precaution with no downside in a thread in which a serious accident is discussed that this precaution would have avoided?
also, grabbing the belayer's side of the rope until you are sure they have you will only protect you from a belayer who just never locks off at all. it won't protect you from jack shit if the belayer loses control of the rope while they are lowering. the second possibility seems just as likely for glbauer's story.
(This post was edited by drivel on Apr 27, 2010, 11:58 PM)
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dingus
Apr 28, 2010, 12:01 AM
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drivel wrote: jt512 wrote: .... Finally, any time you have the opportunity to take responsibility for your own safety in climbing, and you fail to do so, you just plain fail. so why don't you just rap every time you clean the anchors? jt512 wrote: P.S. How can you not feel at least a little bit stupid arguing against a safety precaution with no downside in a thread in which a serious accident is discussed that this precaution would have avoided? also, grabbing the belayer's side of the rope until you are sure they have you will only protect you from a belayer who just never locks off at all. it won't protect you from jack shit if the belayer loses control of the rope while they are lowering. the second possibility seems just as likely for glbauer's story.
Why does J giving himself a 2nd chance to recover from some stupid communication mistake (for example), trouble you so much???
I just don't get this. I truly don't.
DMT
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jt512
Apr 28, 2010, 12:02 AM
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drivel wrote: jt512 wrote: .... Finally, any time you have the opportunity to take responsibility for your own safety in climbing, and you fail to do so, you just plain fail. so why don't you just rap every time you clean the anchors?
Why don't you just read the thread?
In reply to: also, grabbing the belayer's side of the rope until you are sure they have you will only protect you from a belayer who just never locks off at all. it won't protect you from jack shit if the belayer loses control of the rope while they are lowering.
It also won't protect you from food poisoning, West Nile Virus, earthquakes, or sudden cardiac death. But, guess what? It will protect you if your belayer didn't put you on tension.
Jay
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drivel
Apr 28, 2010, 12:08 AM
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jt512 wrote: drivel wrote: jt512 wrote: .... Finally, any time you have the opportunity to take responsibility for your own safety in climbing, and you fail to do so, you just plain fail. so why don't you just rap every time you clean the anchors? Why don't you just read the thread? In reply to: also, grabbing the belayer's side of the rope until you are sure they have you will only protect you from a belayer who just never locks off at all. it won't protect you from jack shit if the belayer loses control of the rope while they are lowering. It also won't protect you from food poisoning, West Nile Virus, earthquakes, or sudden cardiac death. But, guess what? It will protect you if your belayer didn't put you on tension. Jay
just finished readin' the thread. i agree that rapping is more dangerous than lowering, but that wasn't my point. my point is that, when rapping, you take responsibility for your own safety. when lowering, you let someone else take responsibility for your safety, when you could have done it yourself, therefore, according to you:
In reply to: any time you have the opportunity to take responsibility for your own safety in climbing, and you fail to do so, you just plain fail.
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drivel
Apr 28, 2010, 12:09 AM
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dingus wrote: drivel wrote: jt512 wrote: .... Finally, any time you have the opportunity to take responsibility for your own safety in climbing, and you fail to do so, you just plain fail. so why don't you just rap every time you clean the anchors? jt512 wrote: P.S. How can you not feel at least a little bit stupid arguing against a safety precaution with no downside in a thread in which a serious accident is discussed that this precaution would have avoided? also, grabbing the belayer's side of the rope until you are sure they have you will only protect you from a belayer who just never locks off at all. it won't protect you from jack shit if the belayer loses control of the rope while they are lowering. the second possibility seems just as likely for glbauer's story. Why does J giving himself a 2nd chance to recover from some stupid communication mistake (for example), trouble you so much??? I just don't get this. I truly don't. DMT
it doesn't fucking trouble me. when i clean anchors, i use 24" slings so that i have enough room to make sure the belayer well and truly has me in tension before i unclip myself. same logic, different method.
my actual beef is with his absolutism on the "you fail" statement. see my post above this one.
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dingus
Apr 28, 2010, 12:10 AM
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Ah I see, its all about jt512.
Enjoy!
DMT
(This post was edited by dingus on Apr 28, 2010, 12:10 AM)
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drivel
Apr 28, 2010, 12:13 AM
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dingus wrote: Ah I see, its all about jt512. Enjoy! DMT
about his statement, and the absurdity of it, re; rappelling vs lowering, and "personal responsibility," yeah. mostly cause, as i said above, i really do agree that lowering is safer. and yet, you COULD 'take responsibility for yourself' and rap. so as not to be a failure in jay's book. yeah.
(This post was edited by drivel on Apr 28, 2010, 12:15 AM)
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drivel
Apr 28, 2010, 12:14 AM
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dingus wrote: Ah I see, its all about jt512. Enjoy! DMT
alternate response:
i just want jay to pay attention to me. this is the only way i can get it.
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jt512
Apr 28, 2010, 12:16 AM
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drivel wrote: jt512 wrote: drivel wrote: jt512 wrote: .... Finally, any time you have the opportunity to take responsibility for your own safety in climbing, and you fail to do so, you just plain fail. so why don't you just rap every time you clean the anchors? Why don't you just read the thread? In reply to: also, grabbing the belayer's side of the rope until you are sure they have you will only protect you from a belayer who just never locks off at all. it won't protect you from jack shit if the belayer loses control of the rope while they are lowering. It also won't protect you from food poisoning, West Nile Virus, earthquakes, or sudden cardiac death. But, guess what? It will protect you if your belayer didn't put you on tension. Jay just finished readin' the thread. i agree that rapping is more dangerous than lowering, but that wasn't my point. my point is that, when rapping, you take responsibility for your own safety. when lowering, you let someone else take responsibility for your safety, when you could have done it yourself, therefore, according to you: In reply to: any time you have the opportunity to take responsibility for your own safety in climbing, and you fail to do so, you just plain fail. ... you fail.
Fine. I fail. Now dirt me.
Jay
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drivel
Apr 28, 2010, 12:17 AM
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jt512 wrote: drivel wrote: jt512 wrote: drivel wrote: jt512 wrote: .... Finally, any time you have the opportunity to take responsibility for your own safety in climbing, and you fail to do so, you just plain fail. so why don't you just rap every time you clean the anchors? Why don't you just read the thread? In reply to: also, grabbing the belayer's side of the rope until you are sure they have you will only protect you from a belayer who just never locks off at all. it won't protect you from jack shit if the belayer loses control of the rope while they are lowering. It also won't protect you from food poisoning, West Nile Virus, earthquakes, or sudden cardiac death. But, guess what? It will protect you if your belayer didn't put you on tension. Jay just finished readin' the thread. i agree that rapping is more dangerous than lowering, but that wasn't my point. my point is that, when rapping, you take responsibility for your own safety. when lowering, you let someone else take responsibility for your safety, when you could have done it yourself, therefore, according to you: In reply to: any time you have the opportunity to take responsibility for your own safety in climbing, and you fail to do so, you just plain fail. ... you fail. Fine. I fail. Now dirt me. Jay
for posterity.
......but you have to let go of the rope first.
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dingus
Apr 28, 2010, 12:19 AM
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drivel wrote: dingus wrote: Ah I see, its all about jt512. Enjoy! DMT about his statement, and the absurdity of it, re; rappelling vs lowering, and "personal responsibility," yeah.
I know dude but on the other hand we both know what he meant.
Anyway, back to topic... I know it irrational (to some extent), but at the sport anchors of an overhanging lower off, right before I ease onto the rope I imagine, just for a second, free falling backwards.
I also know, from personal experience, the sound of crunching bones. Its one of my fears, to get dropped like that and statistics sadly, bear this fear out as ligit.
I use whatever slingage I have handy. Sometimes girthed to my harness, sometimes run through the tie in points, sometimes clipped willy nilly chain draw style.
I still check the belayer has me before committing to the rope - every time. And the worse condition the anchor the more gently I do the easing on.
DMT
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drivel
Apr 28, 2010, 12:21 AM
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dingus wrote: drivel wrote: dingus wrote: Ah I see, its all about jt512. Enjoy! DMT about his statement, and the absurdity of it, re; rappelling vs lowering, and "personal responsibility," yeah. I know dude but on the other hand we both know what he meant.
jay is such a logic nazi, though. i mean, dude.
In reply to: I still check the belayer has me before committing to the rope - every time. And the worse condition the anchor the more gently I do the easing on.
werd. every time.
(This post was edited by drivel on Apr 28, 2010, 12:21 AM)
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edge
Apr 28, 2010, 12:30 AM
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Rule 1. Climbing is potentially dangerous.
Rule 2. You are responsible for your own safety.
Rule 3. Learn the rules, the exceptions, and choose your partners accordingly.
Rule 4. If your belayer is the primary beneficiary of your insurance, or even if not, consider them suspect. Hell, even if your Mom is belaying you and Dad has left everything to Mom in the event of you dying in a climbing accident, then keep a close eye on Mommy.
Rule 5. The above are vast over-reactions. However, if you could do something ridiculously easy, like mentioned above, why wouldn't you? Seriously, what have you got to gain by blind trust, other than giving your belayer a false sense of security?
I have had people who I would take a bullet for belay me, and I would still never trust them 100% if I could back up their next move with a pre-emptive strike.
I alone am responsible for my own safety. If I use a belayer, that is my personal choice based on my accumulated knowledge.
If I make a mistake picking out a partner, then that is my fault. If I do not, then obviously I picked the right person to help me reach my goals.
Of course, accidents can and will happen. Accident's by definition, are unexpected.
Me grabbing the rope to double check on my belayer may be unexpected to them, but makes perfect sense as a preemptive strike to me.
Really, to repeat myself, why wouldn't you? Blind trust is both.
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