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chossmonkey


Oct 30, 2007, 9:40 AM
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Re: [microbarn] Gear Tuggers know nothing??? [In reply to]
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microbarn wrote:
chossmonkey wrote:
microbarn wrote:
roclmbr wrote:
I think a simple physics lesson will tell you that tugging a piece of pro will not give any indication about whether it will hold a fall or not. The forces in a fall vary a lot, but can easily reach over a 1000 lbs, with a theoretical limit towards 4000 lbs. This is the force on the top piece. This is about the weight of a car. Now image yourself hanging off a cliff by one hand and pulling on a sling with the other. How close to lifting that car off the ground do you think you will come. Tugging is only good to check whether the piece is well placed and this would be better served by gently pulling and watching to make sure it is seated well.

I don't claim that a tug is going to be that strong.

You pretty much did in your first post by putting a sharp tug just below a hard fall.

I placed it higher than low fall factor falls. This isn't enough to activate a screamer or move a truck. I don't think it is essential to my point either way.
I guess a 'low fall factor' is very open to a lot of interpretation.

For what its worth according to the chart at Yates a FF of just .05 puts 3.8kN onto the anchor you're falling on.


Partner cracklover


Oct 30, 2007, 9:59 AM
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Re: [microbarn] Gear Tuggers know nothing??? [In reply to]
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microbarn wrote:
cracklover wrote:
stymingersfink, you are mistaken in a variety of ways. I think I spelled out the forces pretty well in my post above. It doesn't seem to be an issue of you not getting it, but not even trying to. For that, clarifying my points will do nothing, so I'll leave it alone.

Cheers,

GO

I think Sty is right.

Nope. Even if he was correct that the peak force from sitting back on a dynamic line is not higher than the weight of the climber, he is still wrong about his calculation on the force the top piece feels. It would not feel 2X the weight of the climber, but ~ 1.6X. Do you know why?

In reply to:
I would like a link to rgold's post that you referred to or a better explanation. You are just giving the jt512 validation right now.

I will provide a link shortly (as soon as I track it down!) Meanwhile, if you don't actually care about the math, you can just confirm his results by going to the Petzl fall simulator. Put in a fall factor zero, and you will see it reports the force on the top piece at ~ 3.4 times the weight of the climber.

GO


(This post was edited by cracklover on Oct 30, 2007, 10:10 AM)


granite_grrl


Oct 30, 2007, 10:41 AM
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Re: [cracklover] Gear Tuggers know nothing??? [In reply to]
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cracklover wrote:
Nope. Even if he was correct that the peak force from sitting back on a dynamic line is not higher than the weight of the climber, he is still wrong about his calculation on the force the top piece feels. It would not feel 2X the weight of the climber, but ~ 1.6X. Do you know why?

Do you know why? In the simplist form, ignoring and losses from friction, etc it is 2x the climber's weight. But any one who has a mediocer understanding of physics would understand that there will never be exactly 2x the person's weight on the rope.

Likewise to proclaim that it's very close to 1.6x is also ignorant. How much friction is there? What is the angle of the rock? Does the person have one or two legs (or nothing) thouching the rock? Does the person have a nice little ledge to put their feet on? Is the person hanging straight down or are they pushing back from the peice? Simplier to just do a basic calc sans friction, vectors, etc.

Edited to add that I haven't done a statics course since second year university and I'd like to cracklover the benifit of the doubt and have him explain his calcs a little better.


(This post was edited by granite_grrl on Oct 30, 2007, 10:50 AM)


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Oct 30, 2007, 10:49 AM
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Re: [microbarn] Gear Tuggers know nothing??? [In reply to]
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microbarn wrote:
I suppose I am just trying to learn from others' experiences.

Sure doesn't sound like it. My experience (and the experience of others on this thread) has shown that the force applied on a cam (in the direction of the stem) is nowhere near enough to rip it out of a poor placement unless the placement is obviously crap. I'm telling you, when I was testing Aliens, I placed a bunch of cams, tugged on 'em all, they held great. Until I found good enough placements, none could hold the 3-4kN that I was testing them to. Ripped 'em all right out.

How much force do you think your tug is putting on your gear? I really don't know what you think. You say both:
In reply to:
I believe it is possible to generate 3 times my weight with a sling.
and
In reply to:
I don't think a tug approaches three times our weight. It definitely would be much less.

So which do you actually think? Go ahead - take my earlier suggestion: Go to the gym, take a stack of the big 45 lb iron weights. The kind that fit on a barbell. Put your sling through the middle of them, and give them a nice upward tug, just like you would give your gear a downward tug. See if they budge. If they do, congratulations, you can generate 2kN of peak force with a tug. Please let me know I'm wrong, and I'll send you a beer. If they don't - I'm sorry you've bruised your hand trying. Next time, think about it a little harder.

In reply to:
Everyone that says tugs are worthless hasn't had any reasoning to back that up.

Nonsense. I gave specific examples, and so have other posters.

In reply to:
All of the above logic is why I was hesitant to believe your figures earlier. I believe it is possible to generate 3 times my weight with a sling. You didn't, and I don't have a screamer to test my theory.

Can you please explain what is wrong with my logic?

In reply to:
Perhaps we should go dig up rgold's force calculations, and then we can prove it with numbers? Probably not worth the effort. This is a branch of the discussion that doesn't really even relate to the thread.

I brought it up, so if it doesn't relate to the thread, I apologize. But I thought you wanted to know if tugging was useful. Your premise is that it is, because it generates a force equivalent to a small fall. I tried to explain the amount of force various things put on the gear, to show that you were mistaken, and to give both real-world examples and mathematical explanations.

On cams, tugging in the direction of the stem is not useful because the amount of force generated is miniscule compared to even a small fall. Because it works by friction, miniscule forces are simply useless in telling you how well a cam (or tricam) will perform given a force up in the kilonewton+ range. That's why the cam will not just fall out of a poor placement (in flaring cracks, crumbly rock, dirty cracks, slimy cracks, polished cracks, soft stone).

GO


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Oct 30, 2007, 11:05 AM
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Re: [granite_grrl] Gear Tuggers know nothing??? [In reply to]
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granite_grrl, I agree that that level of precision in calculating a toprope fall is not relevant to this discussion. It was merely part of a larger point I was making.

But I hope you're not suggest that 2 is *more* accurate than 1.6-1.7. In simplest terms, at rest, a belayer standing on the ground will put approximately (that's what the little "~" sign means) 2/3 the amount of force on the belay strand as the climber at rest puts on the other strand (irrelevant to any intermediate protection between the belayer and the top piece, or any friction between the rope and rock between the belayer and top piece).

Of course, if the belayer sits down and holds herself up with the friction on the belay device, the top piece will feel the weight of the belayer plus the weight of the climber, which would indeed be ~ 2X the weight of the climber.

Make sense?

GO


granite_grrl


Oct 30, 2007, 11:18 AM
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Re: [cracklover] Gear Tuggers know nothing??? [In reply to]
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cracklover wrote:
granite_grrl, I agree that that level of precision in calculating a toprope fall is not relevant to this discussion. It was merely part of a larger point I was making.

But I hope you're not suggest that 2 is *more* accurate than 1.6-1.7. In simplest terms, at rest, a belayer standing on the ground will put approximately (that's what the little "~" sign means) 2/3 the amount of force on the belay strand as the climber at rest puts on the other strand (irrelevant to any intermediate protection between the belayer and the top piece, or any friction between the rope and rock between the belayer and top piece).

Of course, if the belayer sits down and holds herself up with the friction on the belay device, the top piece will feel the weight of the belayer plus the weight of the climber, which would indeed be ~ 2X the weight of the climber.

Make sense?

GO

Okay, you'll get off easy this time!! ;)

To me it wasn't clear that you assumed that the belayer was getting pulled off the ground and adding his weight minus the friction of every peice in between to the force seen by the top piece.

Enough of this silly statics and dynamics talk. There's a reason why I didn't go into mechanical engineering. Electricity is much more predictable and maliable.

As far as thread drift goes....unless someone actually has a mesurment of the force that's generated by yarding on a peice of gear, this thread will just keep going around in circles.


roclmbr


Oct 30, 2007, 11:26 AM
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Re: [microbarn] Gear Tuggers know nothing??? [In reply to]
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Static test versus dynamic test of climbing protection


To compare the 2 methods of testing protection we need to make some assumptions:

1. How strong is a static test.

Since this is more controlled than a dynamic test we can use more of our body mass to pull. If we were to perform a dynamic test with all our power it would put us in a very dangerous position if the piece failed. Real world experience shows that a dynamic test (tug) is performed mostly with the arm.

A strong pull could probably lift a 90 lb (40 Kg) load off the ground an inch or so. This corresponds to a force of 400 Newton.

2. Dynamic test.

How fast is the protection traveling during the tug?

A baseball pitcher throws a baseball at a velocity of 44 m/s, and gravity would have the pro traveling at 3 m/s after 50 cm. I used 50 cm to simulate a 25 cm sling being pulled up then down. Assuming that our tug will not be anywhere near as fast as a baseball from a pitcher the velocity of the pro is assumed to be 10 m/s.

Nylon slings will stretch about 5% under small loads (more under heavier loads. I have stretched slings 100% before they broke) which will give us a stretch of 1.25 cm. This is the distance over with the braking will occur and allows us to calculate the acceleration during the application of the tug.

a=(v.v)/2x = 100/0.025 = 4000 m/s

Assuming a mass of 100g for sling and pro this gives a force of

F = ma = 0.1 x 4000 = 400 Newton

Comparing the 2 forces we can see that they are the same, therefore I would suggest that it is better to exert a controlled force rather than a dynamic one.

This assumes the intent is to generate the maximum force on the pro. It is interesting to note that the forces are about 1/5th the force that could theoretically be generated in a fall.


microbarn


Oct 30, 2007, 11:52 AM
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Re: [cracklover] Gear Tuggers know nothing??? [In reply to]
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cracklover wrote:
microbarn wrote:
I suppose I am just trying to learn from others' experiences.

Sure doesn't sound like it. My experience (and the experience of others on this thread) has shown that the force applied on a cam (in the direction of the stem) is nowhere near enough to rip it out of a poor placement unless the placement is obviously crap. I'm telling you, when I was testing Aliens, I placed a bunch of cams, tugged on 'em all, they held great. Until I found good enough placements, none could hold the 3-4kN that I was testing them to. Ripped 'em all right out.

You weren't posting any of this unprompted. I am playing devil's advocate to a great extent to hear people's reasoning.

In reply to:
How much force do you think your tug is putting on your gear? I really don't know what you think. You say both:
In reply to:
I believe it is possible to generate 3 times my weight with a sling.
and
In reply to:
I don't think a tug approaches three times our weight. It definitely would be much less.

So which do you actually think? Go ahead - take my earlier suggestion: Go to the gym, take a stack of the big 45 lb iron weights. The kind that fit on a barbell. Put your sling through the middle of them, and give them a nice upward tug, just like you would give your gear a downward tug. See if they budge. If they do, congratulations, you can generate 2kN of peak force with a tug. Please let me know I'm wrong, and I'll send you a beer. If they don't - I'm sorry you've bruised your hand trying. Next time, think about it a little harder.

You are taking the quotes out of context. I believe a person with a sling/aiders can generate three times their weight in a bounce test. I believe a tug is going to be dramatically less because we can't apply our full body weight or jump from higher steps with abandon.

To have a worst case scenario bounce test, one can loop their bottom foot in the bottom step of an aider. Stand on the second to last step. Jump up. Just before your weight hits the bottom step, jump from the bottom step.

Your weight + height fallen + jumping + no elongation = enormous force for a split second....I would be surprised it this wasn't at least 3 times the weight of the person executing it.

Your example of lifting the weights does not apply because all of the above utilizes gravity.

If all of that isn't enough to get three times your weight, then you could always follow Sty's suggestion. Put the screamer on a redirect piece and essentially double your forces. (Yes, minus friction which wouldn't be much since there is limited sling elongation.)

In reply to:
In reply to:
Everyone that says tugs are worthless hasn't had any reasoning to back that up.

Nonsense. I gave specific examples, and so have other posters.

In reply to:
All of the above logic is why I was hesitant to believe your figures earlier. I believe it is possible to generate 3 times my weight with a sling. You didn't, and I don't have a screamer to test my theory.

Can you please explain what is wrong with my logic?

From your recent posts, I now gather that you meant the force on the top piece of gear. Earlier, I was taking your statements to mean the force on the climber. This is probably my mistake in reading too quickly. Above I explained where I expect the bounce test forces to be much higher than your findings.

In reply to:
In reply to:
Perhaps we should go dig up rgold's force calculations, and then we can prove it with numbers? Probably not worth the effort. This is a branch of the discussion that doesn't really even relate to the thread.

I brought it up, so if it doesn't relate to the thread, I apologize. But I thought you wanted to know if tugging was useful. Your premise is that it is, because it generates a force equivalent to a small fall. I tried to explain the amount of force various things put on the gear, to show that you were mistaken, and to give both real-world examples and mathematical explanations.

Perhaps what I bolded explains why we are failing to see eye to eye. My premise is not that a tug generates a force equivalent to a small fall, but that there is some non-negligible force that a tug generates. Using that statement I move on to say "If a placement fails during a tug, then I should not use that placement."

roclmbr, I saw your post, but I don't have time to address it. I will try to post again tonight if others don't already reply.


microbarn


Oct 30, 2007, 12:31 PM
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Re: [roclmbr] Gear Tuggers know nothing??? [In reply to]
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copying your equation from your 'dynamic' section and altering:

F = ma = (0.1 + mass of arm) x 4000 + (your definition of 'static force') = way more force

I will leave it to you to make up the numbers.

roclmbr wrote:
Static test versus dynamic test of climbing protection


To compare the 2 methods of testing protection we need to make some assumptions:

1. How strong is a static test.

Since this is more controlled than a dynamic test we can use more of our body mass to pull. If we were to perform a dynamic test with all our power it would put us in a very dangerous position if the piece failed. Real world experience shows that a dynamic test (tug) is performed mostly with the arm.

A strong pull could probably lift a 90 lb (40 Kg) load off the ground an inch or so. This corresponds to a force of 400 Newton.

2. Dynamic test.

How fast is the protection traveling during the tug?

A baseball pitcher throws a baseball at a velocity of 44 m/s, and gravity would have the pro traveling at 3 m/s after 50 cm. I used 50 cm to simulate a 25 cm sling being pulled up then down. Assuming that our tug will not be anywhere near as fast as a baseball from a pitcher the velocity of the pro is assumed to be 10 m/s.

Nylon slings will stretch about 5% under small loads (more under heavier loads. I have stretched slings 100% before they broke) which will give us a stretch of 1.25 cm. This is the distance over with the braking will occur and allows us to calculate the acceleration during the application of the tug.

a=(v.v)/2x = 100/0.025 = 4000 m/s

Assuming a mass of 100g for sling and pro this gives a force of

F = ma = 0.1 x 4000 = 400 Newton

Comparing the 2 forces we can see that they are the same, therefore I would suggest that it is better to exert a controlled force rather than a dynamic one.

This assumes the intent is to generate the maximum force on the pro. It is interesting to note that the forces are about 1/5th the force that could theoretically be generated in a fall.

um, 1/5th the force of a fall? That still seems pretty substantial to me. (Also, where are you getting the maximum fall force?)

The same statement again applies:
If a placement fails with 1/5th the force of a fall, then I would like know and make a different placement to protect my climbing.


Partner cracklover


Oct 30, 2007, 12:55 PM
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Re: [microbarn] Gear Tuggers know nothing??? [In reply to]
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microbarn wrote:
cracklover wrote:
microbarn wrote:
I suppose I am just trying to learn from others' experiences.

Sure doesn't sound like it.

You weren't posting any of this unprompted. I am playing devil's advocate to a great extent to hear people's reasoning.

Okay, well if you're taking a stance you don't really believe, simply to hear people's reasoning, then perhaps you are trying to learn.

In reply to:
Your weight + height fallen + jumping + no elongation = enormous force for a split second....I would be surprised it this wasn't at least 3 times the weight of the person executing it.

I couldn't generate it with a simple bounce test, but feel free to give it a shot. Oh, don't get me wrong, I found a way to generate that force, I'm just saying I couldn't do it with a simple bounce test.

In reply to:
Your example of lifting the weights does not apply because all of the above utilizes gravity.

Huh? The force required to lift 450 lbs is... (drumroll please)... 450 lbs! Lbs are a unit of force. This is not complex science, this is 1=1!

In reply to:
From your recent posts, I now gather that you meant the force on the top piece of gear. Earlier, I was taking your statements to mean the force on the climber. This is probably my mistake in reading too quickly. Above I explained where I expect the bounce test forces to be much higher than your findings.


Yes, that's the point. You think you can generate more force with a bounce and with a tug than you can. Go ahead, go to the to the gym, give it a shot and let us know. If the stack of ten heavy plates moves up at all, you have put a higher force on it than gravity (450 lbs). Simple test, really. I'm not going to bruise my hand on a sling to do it, though; I leave it up to you. And if you can't lift a stack of 10 heavy plates with a sharp tug, try 9. Try 8. Let me know what it winds up being, I'm curious. And if you think this is silly, then you're right, it is. The idea of lifting a stack of ten heavy iron plates with a flick of your forearm is exactly as silly as testing a cam this way, for exactly the same reason!

In reply to:
My premise is not that a tug generates a force equivalent to a small fall...

In reply to:
1) holds its own weight and the weight of the rope.
2) holds body weight and a slow transition onto the piece is required
3) holds a top rope fall (body weight applied quickly)
4) holds a fall with a low fall factor
5) holds a sharp tug from the climber
6) holds any fall

Um... Dude? That's what you said! Laugh How many sides of the fence do you want to play?

In reply to:
... but that there is some non-negligible force that a tug generates.

Which is also wrong (for cams). It's negligible.

Just admit that you're wrong and move on.

GO


microbarn


Oct 30, 2007, 1:24 PM
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Re: [cracklover] Gear Tuggers know nothing??? [In reply to]
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You seem determined to mix bounce test forces with tugging forces. I give up arguing with you on that front. I see these two as distinct items, but above you mingle everything with no distinction.

Others in this thread are saying good looking placements are failing under loads of a good yank: (my bold)

microbarn wrote:
notapplicable wrote:
I don't think it fair or accurate to say that tugging on a piece will or wont provide you with valuable info. 100% of the time. Some placements (especially passive) are so obviously solid that yanking on them is only going to serve the purpose of seating the gear and won't provide you with any new info. On the other hand I have had just about every kind of piece (passive and active) pull with just a swift yank, when I thought they would hold fine. For what its worth, having gear fail while testing it has caused me to nearly fall so there are risks associated with the behavior.

I yank on just about every placement. Some of them hard, to test placement quality and some gently, just to set them.

I have found it to be a useful practice and doing so can provide a climber with valuable information, while not doing so could leave you in the dark.

and that is the benefit of tugging in my eyes. You at least rule out that there is something obviously wrong. If you don't tug on those pieces, then you are possibly climbing into dangerous situations thinking you are well protected.

Your only response to this seems to be "MY placements either hold or they look really bad." Did I miss another response to this? Is there anything else that you want to say with respect to this?


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Oct 30, 2007, 1:47 PM
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microbarn wrote:
Is there anything else that you want to say with respect to this?

I would like to point out that "Gear Tugging" is a euphemism for masturbation.

Angelic


microbarn


Oct 30, 2007, 1:57 PM
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dominic7 wrote:
microbarn wrote:
Is there anything else that you want to say with respect to this?

I would like to point out that "Gear Tugging" is a euphemism for masturbation.

Angelic

I debated about entitling the thread "Pro Tuggers know nothing," but I never would have gotten a useful response to the thread.


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Oct 30, 2007, 2:17 PM
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Re: [microbarn] Gear Tuggers know nothing??? [In reply to]
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microbarn wrote:
You seem determined to mix bounce test forces with tugging forces. I give up arguing with you on that front. I see these two as distinct items, but above you mingle everything with no distinction.

How so? Where am I mixing up my forces? You are the one dodging questions and changing your story every few posts. I've given you a challenge. Go see how much force your tug really has and report back. Put up or shut up.

In reply to:
Others in this thread are saying good looking placements are failing under loads of a good yank: (my bold)

notapplicable wrote:
I have had just about every kind of piece (passive and active) pull with just a swift yank, when I thought they would hold fine.

Your only response to this seems to be "MY placements either hold or they look really bad." Did I miss another response to this? Is there anything else that you want to say with respect to this?

I would respectfully suggest that notapplicable was either not yet proficient at analyzing his gear in general, or on that specific rock, at the time that this happened. Simply put - even halfway good cams can't get yanked out in the direction of force. As I've said several times (and perhaps this is what notapplicable meant in relation to his failing cams) if you have a marginal cam, and you're not sure about the contact of one or more of the lobes, yanking it sideways *can* produce enough torque to show that those lobes aren't biting. Even though yanking it directly probably would not cause it to fail! That's how useless a direct yank is! The piece will often stay in place on just one lobe!

So to use your original list, here is how I would categorize the strength of cam and tricam placements:

1) holds its own weight and the weight of the rope.
1.01) holds a sharp tug from the climber
2) holds body weight and a slow transition onto the piece is required
2.8) holds vigorous bounce test
3) holds a top rope fall (body weight applied quickly)
4) holds a fall with a low fall factor
5) holds any fall

GO


stymingersfink


Oct 30, 2007, 2:43 PM
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So far, the only thing I've gotten from this thread is that some people do not generate very high loads when bounce testing.

Ergo, I would correlate that on those really dicey pitches with nothing but copperheads should be lead by the lightest person.

Crazy


ajkclay


Oct 30, 2007, 5:32 PM
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... and I learnt that there's more than one way to say "Nyahey!"

Umm to an earlier question, I learnt on quartzite. Nice, clean solid rock with good placements.

No need to tug anything except to "seat something to stop dislodging from friction. Unless of course one has a problem with finding and recognising decent placements. Visual inspection generally suffices. And once I'm past a piece it's good, it's good, it's good... honest, it will hold, it will!

I am aware of a number of instances where climbers have fallen while tugging on gear and decked as a result - interestingly they seem to happen frequently in positions where a fall would not have occured without the tug.

It is an important consideration I think - if you are a tugger, make sure that your balance will not be jeopardised if the piece comes out while you're tugging.

Cheers tuggers!

Adam Smile


(This post was edited by ajkclay on Oct 30, 2007, 5:34 PM)


roclmbr


Oct 31, 2007, 4:55 AM
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Re: [microbarn] Gear Tuggers know nothing??? [In reply to]
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In reply to:
"microbarn"]copying your equation from your 'dynamic' section and altering:

F = ma = (0.1 + mass of arm) x 4000 + (your definition of 'static force') = way more force

I will leave it to you to make up the numbers.

It is always difficult to figure out how simple you can make a problem and still get a valid result. I agree that you could probably include the mass of the hand, however if you include the mass of the arm then you have to start to include the upward pull caused by the resistance of the sling, pro etc. Assuming that you don't start applying more force when you feel the resistance of the sling then I believe the force will be diminishing and the maximum force will be less than at the point of impact. I am not sure of the mass of the hand, but it would certainly increase the total force.

The main point is that the magnitude of the forces generated either by tugging or by pulling, in a real world situation, are in the same realm. Therefore, it is better to perform a controlled pull to test the placement.

Whether 1/5th the fall force is sufficient is up to debate. In some cases, insufficient force will not give an accurate representation of what will happen under full force. How many times have you seen climbers test a foot hold by placing the shoe on the hold without weighting it, only to have the foot slip off. However, confident climbers will use the same hold by committing their weight to it. The amount of holding power is dependant on the force applied. The same may apply with cams since their holding power is generated by friction.


microbarn


Oct 31, 2007, 8:41 AM
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Re: [roclmbr] Gear Tuggers know nothing??? [In reply to]
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roclmbr wrote:
The main point is that the magnitude of the forces generated either by tugging or by pulling, in a real world situation, are in the same realm. Therefore, it is better to perform a controlled pull to test the placement.

I agree with you. A controlled tug is often almost as good of a test, and it won't pull someone off balance. If I am in a balancy situation I won't do the same tug as I would on a hands free ledge. However, if I were trying to test a piece for security, I would want to maximize my test force. The dynamic test would be the maximum I could do while free climbing. I let the situation determine how close I approach that max.

In reply to:
Whether 1/5th the fall force is sufficient is up to debate. In some cases, insufficient force will not give an accurate representation of what will happen under full force. How many times have you seen climbers test a foot hold by placing the shoe on the hold without weighting it, only to have the foot slip off. However, confident climbers will use the same hold by committing their weight to it. The amount of holding power is dependant on the force applied. The same may apply with cams since their holding power is generated by friction.

Good example with the feet slipping when climbers don't commit their weight. I don't believe this is the case with cams. Cams increase the outward force in proportion to their load. Friction is proportional to the normal force. A tug that generates outward forces exceeding the standard spring tension on a cam will give an idea of how a cam will perform.

We aren't running hard numbers, so let's make the assumption that you are correct. A given placement will not hold a tug, but it will hold a fall. Below is my response.

Let's say you come to a place where your foot slips when you don't commit your weight. Wouldn't you rather find a place where it sticks with minimal weight commitment? This would imply better friction, and it would provide a better safety margin during use. Also, there are times where I committed 100% of my weight onto my shoes and they still slipped.

Applying your analogy to gear, I would rather know the safety margin is not present. I can choose to look for a better place, or I can try to adjust the current placement. If there is no better placement available, then maybe I will have to make do. At least I know that piece isn't bomber, and I can look to back it up as soon as possible above it.

ajkclay wrote:
I am aware of a number of instances where climbers have fallen while tugging on gear and decked as a result - interestingly they seem to happen frequently in positions where a fall would not have occured without the tug.

It is an important consideration I think - if you are a tugger, make sure that your balance will not be jeopardised if the piece comes out while you're tugging.
Excellent point! Any time one tugs, you should be prepared for a failure.

A friend who is a guide pulled on an old anchor during a trip to patagonia. It pulled and he fell an estimated 90 feet. He ended up going to the hospital.

cracklover,
Perhaps you are right. Maybe you have a better eye for placements than ALL the guides, and ALL the other trad climbers that have pulled out good looking placements. I don't believe I am infallible or exempt from the physics that rule others. If I am currently well protected and the crux is coming up, I will probably continue to tug on that piece. I will probably tug on blindly placed pieces. I may tug on others too. I will probably continue to avoid tugging on the first piece after a run out or mid crux. I will probably tug more often on the polished Seneca climbs and on limestone. I won't assume the piece is bomber just because it held a tug, but I will be able to quiet my mind just a little bit. It will make the unknowns with respect to that placement slightly smaller.

(I still am interested in the rgold link if you have it.)


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Oct 31, 2007, 8:52 AM
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Re: [microbarn] Gear Tuggers know nothing??? [In reply to]
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Apologies if this has already been covered, but gear tuggers know if their cams will hold in a horizontal flare or if the angle is just too wide.


notapplicable


Oct 31, 2007, 9:00 AM
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j_ung wrote:
Apologies if this has already been covered, but gear tuggers know if their cams will hold in a horizontal flare or if the angle is just too wide.

Yeah, I have definently confirmed the worthlesness of a few placements at the Gunks and Looking Glass with one swift jerk.

I would say that testing gear with a tug falls into the 'Not always needed but sometimes useful' catagory. But doesnt just about everthing in life. If somebody wants to call me a gumby for testing gear I got no beef, it serves a purpose for me.


notapplicable


Oct 31, 2007, 9:42 AM
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Re: [microbarn] Gear Tuggers know nothing??? [In reply to]
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ajkclay wrote:
I am aware of a number of instances where climbers have fallen while tugging on gear and decked as a result - interestingly they seem to happen frequently in positions where a fall would not have occured without the tug.

It is an important consideration I think - if you are a tugger, make sure that your balance will not be jeopardised if the piece comes out while you're tugging.

Cheers tuggers!

Adam Smile

roclmbr wrote:

Tugging should be avoided since it serves no better purpose than a simply pull and it places the climber in a potential situation where they could be put off balance should the piece pull out. Climbing is about control and tugging is wrong.

cracklover wrote:
Further, there is a very real downside if the piece rips. If there's no benefit, it's just not worth it.

I was doing a little catching up and came across a number instances where this opinion was expressed. It seem to me to be a bit contradictory to the overall position that testing gear with a tug serves no valid purpose.

If you can infact jerk a piece of gear out of the wall then you did confirm that the piece would have not held a fall there by gathering very useful data. If these climbers had climbed 7-8 ft. above that piece and then fallen their situations would have been signifigantly worse.

Concerning the risk of falling as a result of tested gear failing, I think that this sport is full of calculated risks and everyone has to judge for themselves. I dont however think that yanking on a piece is any more sketchy than pulling on one but again every instance is different.

Edited to add cracklovers quote


(This post was edited by notapplicable on Oct 31, 2007, 3:34 PM)


notapplicable


Oct 31, 2007, 10:08 AM
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Re: [cracklover] Gear Tuggers know nothing??? [In reply to]
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cracklover wrote:
I would respectfully suggest that notapplicable was either not yet proficient at analyzing his gear in general, or on that specific rock, at the time that this happened. Simply put - even halfway good cams can't get yanked out in the direction of force. As I've said several times (and perhaps this is what notapplicable meant in relation to his failing cams) if you have a marginal cam, and you're not sure about the contact of one or more of the lobes, yanking it sideways *can* produce enough torque to show that those lobes aren't biting. Even though yanking it directly probably would not cause it to fail! That's how useless a direct yank is! The piece will often stay in place on just one lobe!
GO


While it would be wildly false to claim that I am any type of expert on gear climbing of any kind, I have been at it for awhile now with a relativly steep (read: self taught) learning curve. I am not trying to defend my experience level, it simply is what it is.

You are correct on two fronts.

1. Yes some of the gear I had pull while testing was in the early years of my trad climbing and most of it was due to a poorly executed or missjudged placement.

This however, does not (IMO) invalidate the usefulness of jerk testing a piece of gear because the reality of the situation is that there are alot of novices out there. Testing and having gear fail can serve a very useful role in getting a new climber to the point that they can judge a placement at a mere glance. Tugging on gear may not be a useful tool for all skill levels but that does not invalidate it as an information gathering tool.


2. You are also correct that alot of the times I test a piece of gear, I am trying to get it to fail. Sometimes I am concerned about an odd direction of pull because of the way the rope runs or from where I will be falling. Other times it's because the constiction I am using has a 'back door' and I want to make sure the piece isnt going to walk right out it.


In reference to the cams that have failed with a swift jerk, they are so few I doubt I would need more than half of the fingers on my right hand to count them. Blind placements and flaring cracks tend to be the biggest culprits. So yes I do agree that cams tend to be the most resistant to multi-directional jerks.


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Oct 31, 2007, 10:29 AM
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Re: [microbarn] Gear Tuggers know nothing??? [In reply to]
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microbarn wrote:
We aren't running hard numbers, so let's make the assumption that you are correct. A given placement will not hold a tug, but it will hold a fall.

That just doesn't happen. You display a fundamental lack of understanding here that may be at the root of your larger misunderstanding. As the force in the direction of the stem increases, the cam becomes more, not less likely to pull out. That's what makes a weak pull so useless in determining if the cam will hold a fall.

In reply to:
cracklover,
Perhaps you are right. Maybe you have a better eye for placements than ALL the guides, and ALL the other trad climbers that have pulled out good looking placements.

Now what is the point in discussing my experience if you're going to invalidate it with a ridiculous presumption like that? My eye is no better than your average traddie - I know some rock types well, and others not so well. I never claimed to be able to say if any given placement is 100% bomber or not. I just said that a weak tug on a cam in the direction of pull adds nothing to my knowledge base, if I can see the placement. Doing something of no value is inefficient, and inefficiency on a climb means lower chance of success. Further, there is a very real downside if the piece rips. If there's no benefit, it's just not worth it.

In reply to:
If I am currently well protected and the crux is coming up, I will probably continue to tug on that piece. I will probably tug on blindly placed pieces. I may tug on others too. I will probably continue to avoid tugging on the first piece after a run out or mid crux. I will probably tug more often on the polished Seneca climbs and on limestone. I won't assume the piece is bomber just because it held a tug, but I will be able to quiet my mind just a little bit. It will make the unknowns with respect to that placement slightly smaller.

Okay, sorry I couldn't add to your peace of mind as a gear tugger. That's obviously all you were interested in/capable of getting out of this thread. Your understanding of the degrees of force put on your gear by various different stressors, and the behavior of cams under different stressors, is so far divorced from reality that trying to discuss the single element of gear tugging within the context of the larger realm is a completely worthless endeavor.

Good day.

In reply to:
(I still am interested in the rgold link if you have it.)

Yup, just waiting to hear back from him. If anyone else has a link, that would expedite matters.

GO


microbarn


Oct 31, 2007, 10:45 AM
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Re: [cracklover] Gear Tuggers know nothing??? [In reply to]
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cracklover wrote:
microbarn wrote:
We aren't running hard numbers, so let's make the assumption that you are correct. A given placement will not hold a tug, but it will hold a fall.

That just doesn't happen. You display a fundamental lack of understanding here that may be at the root of your larger misunderstanding. As the force in the direction of the stem increases, the cam becomes more, not less likely to pull out. That's what makes a weak pull so useless in determining if the cam will hold a fall.

You and I agree here. Try reading the paragraph before your quote.

In reply to:
Further, there is a very real downside if the piece rips. If there's no benefit, it's just not worth it.

I already addressed this point, and notapplicable addresses this point just above your post.

In reply to:
Okay, sorry I couldn't add to your peace of mind as a gear tugger. That's obviously all you were interested in/capable of getting out of this thread. Your understanding of the degrees of force put on your gear by various different stressors, and the behavior of cams under different stressors, is so far divorced from reality that trying to discuss the single element of gear tugging within the context of the larger realm is a completely worthless endeavor.

The only reason you provide against tugging is your ability to judge placements perfectly every time. Congrats on your naivety.


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Oct 31, 2007, 10:54 AM
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Re: [j_ung] Gear Tuggers know nothing??? [In reply to]
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j_ung wrote:
Apologies if this has already been covered, but gear tuggers know if their cams will hold in a horizontal flare or if the angle is just too wide.

Really? If I place a cam in a flaring crack, I will definitely not expect a hand-tugging to pull it out, but will make a judgement call as to whether a fall would extract it.

Of course, I mostly aim for the least flaring part of it, or even for an area with a little bulge if I can find one to set even a single lobe behind.

In my experience, as a crack flares more, it becomes unreliable to hold a cam in a fall long before the angle of the flare is high enough for a hand-tug to pull it out. What have you found, Jay?

Oh - except if the crack is parallel on one side, and flaring on the other. In that case, a tug out tells me nothing - it'll still hold even on one cam. Instead, I tug/rotate it in the direction away from the flaring side and see what happens with the flaring lobes. This puts enough torque on the piece to definitely tell me whether the placement is good or not.

GO

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