Which brand of rope do you prefer?

[Shamis]

i break big pieces of metal with a fall factor of 2.

[Redpoint]

Redpoint: In your first depiction it is fall factor 1/3 at most and this is fairly normal.
(Fall factor) = (length of fall)/ (length of rope paid out)

Likewise the second picture from the left is fall factor = 1/2 at most (if there is no more movement in the system after all the action has occurred, the fall factor is less than 1/2).

The third picture from the left is labeled correctly. fall factor = 2 <minus the amount of static elongation in the line due to the climber's weight>

The fourth picture is labeled correctly also. Since the rope did not experience the fall, the fall factor must be 0.

It's my fault you got confused, my diagram in the first two doesn't actually show where the person fell from, but I thought that was obvious.

From what I remember reading, static elongation is already in the formula, because it is how far the climber has fallen(which includes the static elongation), divided by how much rope is paid out. Basically the total distance of the fall(the fall distance) includes the rope stretch. Now when I jabber on below about how high someone climbed and how far they fell, that scenario isn't %100 perfect, because if you climb 10 feet, clip in to a bolt, climb 5 more feet and then fall, you are going to fall a little bit more than 10 feet because of static elongation. That also makes the diagrams a little inaccurate, but my book contains the exact same inaccuracies in it's diagrams as mine. The diagrams just give you a better idea of what a certain fall factor looks like.


In the first depiction, lets say it is 10 feet from the belayer to the first bolt, and if the person is hanging in between that, it means that would be an extra 5 feet of rope added to the 10 which is 15 feet of rope total.

If the person is 5 feet below the bolt that means he fell a total of 10 feet.

10/15 = 0.66

Ok so I was slightly off, the first one is a fall factor of 0.66, not 0.50.

Here is the corrected diagram:

"Fall Factor: The measurement for the hardness of a fall. It is calculated by dividing the distance of the fall, by the length of rope which has been paid out."

An example of a fall factor of .5 would be if you fell 10 feet with 20 feet of rope paid out. For instance if you climbed 15 feet, clipped in to a bolt, and then climbed 5 more feet and then fell 10 feet. Mammut said that as long as you get an excellent dynamic belay for .5 fall factor falls, that your rope could easily last for an entire year if you moderately use the rope(once a weekend).

A new scenario: lets say you climbed 80 feet, clipped in to a bolt, and then climbed 5 more feet and then fell 10 feet. That would have been a fall factor of only 0.11, because 10/85 = 0.11. Now you see why it is better to fall later on in the climb, and why falling early on in the climb is so bad on your rope: fall factors.


I have diagrams in my books for fall factors, and I am good at math, so trust me I know what I'm talking about. It's just my diagram could have been a little better. Too bad I didn't use Photoshop to make the pics, that way I would have had a measurement tool, and then the diagram above would have been %100 perfect the first time I made it.

So far every thorough book about climbing that I have looked at in book stores has had a section with diagrams about fall factors, and from what I have read about them, it seems like a pretty big deal to me.




Now the second picture from the left is perfect, he would have had to climb 20 feet, and then fallen 20 feet in order to end up next to his belayer(in the 10 feet from the belayer to the first bolt scenario). If he climbed 20 feet, and then fell 20 feet, it is quite obvious that 20/20 = 1.

Whenever a climber falls and ends up right next to his belayer with a 100% static belay on a totally vertical wall, that is a fall factor of 1, unless a stickclip was used. For instance using a stick clip you might have 20 feet of rope out and fall 1 foot, and you could end up next to your belayer with a fall factor of just 0.05.

Not only is setting the first bolt really high good for not decking, but it is also good for not letting your rope see a high fall factor, and so is having the second bolt just 3 or 4 feet above the first bolt. Big fall factors are mostly seen while trad climbing, and that is one more reason why it's so hardcore. I am sure that it takes bigger balls to climb trad than it does sport, but that is only if you know what a fall factor is, and also knowing all of the dangers involved with trad climbing. For instance: having to run out, unzipping, or say your nut sliding out of a crack because of an outward pull.

There are some ways to see a high fall factor while sport climbing: having too much slack out, clipping over your head on the second or third bolt, and even rope stretch plays a factor in it all. If you did a multipitch sport route you could even see a fall factor of 2.




NOTE: Slack can contribute to the fall factor scenario, and so it's not just about how high someone climbed and how far they fell, but how much rope is payed out and how far they fell. In my examples above I was referring to no slack being paid out.

ALSO NOTE: "Falls over factor 1, with a fall distance of 5-7 meters, are rated as hard falls." So another thing I learned from Mammut is that how far you fall also contributes to how much it hurts your rope. It figures since you gain more and more speed as you fall, well up to a certain point. A base jumper could surely tell me what the maximum fall speed is and how long it takes before you achieve it..

[Myke Dronez]

I am sure that it takes bigger balls to climb trad than it does sport

Some balls are held for charity and some for fancy dress-
But when they're held for pleasure they're the balls that I like best-

[caribe]

Redpoint: In your first depiction it is fall factor 1/3 at most and this is fairly normal.
(Fall factor) = (length of fall)/ (length of rope paid out).

It's my fault you got confused, my diagram in the first two doesn't actually show where the person fell from, but I thought that was obvious.

___ I was wrong. Your first depiction was ff<2/3 if I give you the benefit of the doubt on those distances.

From what I remember reading, static elongation is already in the formula, because it is how far the climber has fallen(which includes the static elongation), divided by how much rope is paid out.

___ http://tinyurl.com/aje8y4 <Craig Luebben, Mechanical Engineer, inventor of Big Bros.
-tiny ulr: Yasmeen aren't you proud?-
Redpoint, you are not accounting for the pulley effect. See the link above.
___ Regarding terminal velocity . . . you are kidding right? Crack open a physics book. Newton will tell you about the trade off between potential and kinetic energy during a fall on the planet Earth.
___ I don't think that the Fall factor accounts for stretch in rope. The rope stretch is not as aspect of the fall factor per se. For example a factor 1 fall on a dynamic rope (6% static elongation) is going to have a much lower maximum impact force than a factor 1 fall on a static rope (2% static elongation); even though, these fall factors will be pretty equal. This is the reason we use dynamic ropes. Fall factor is simply length of fall over length of rope paid out before the fall and it is used in the calculation of maximum impact force (the important experiential result for both rope, belayer, climber and gear). The max impact force occurs at some point during the arresting of the fall. The impact force plays out over time (broken up in terms of fractions of seconds). This is a cool concept. The following site shows this impact force graphed over the rope elongation during a fall.
http://www.bstorage.com/speleo/Pubs/rle ... efault.htm
___ The graphs above look (perhaps I should have used the graphs forum) like they give the whole story, they don't. It is the important part of the story, but not the whole story. The actual impact force is an integral calculated over the entire time that there remains any motion from the fall in the system. This force is dissipated over time (again in terms of fractions of seconds) harmonically, and dampens quickly over time.
http://en.wikipedia.org/wiki/Harmonic_oscillation
The elastic modulus of the material being fallen on and the attendant points of attachment, points of friction, elastic modulus across the human body, and how dynamically soft the belayer gives the catch all play into the impact force throughout the decay in amplitude of oscillation over time. A nice soft catch results in almost no oscillation.

[caribe]

http://www.bealplanet.com/portail-2006/ ... te&lang=us
Beal's site talks about maximum impact force generated by a fall as a function of rock rub points, rectitude of the line of protect and basically the elastic modulus in the rope. Their point is that their elastic modulus is best. Regardless the infor here is heuristic and worth the read.

[caribe]

Fig 8 above at
http://www.caimateriali.org/index.php?id=45
Displays the quasi oscillatory behavior of the force experienced in the system during a fall. The blue, green and red lines in the graph are simulated forces on the last point of protect, the belayer's harness and the climber's harness respectively. The lighter lines in the graph are experimental data. Note how fast all this happens in terms of fractions of seconds on the x axis.

[ynp1]

i like mammut the best the only problem is the price. i also like sterling and edelweiss a lot. i had an edelweiss last me three years and the only reason i quit using it was because someone gave me a new rope. i also just got a petzl nomad and zypher. i have not used them very much, so i cant say much about there life span, but so far i am very happy with both. i even for a 10.3 rope it feeds very well and clips easily.

oh yeah and you cannot factor 2 on a dynamic rope (or a static rope for that matter, it still stretches 2%). so if you take a fall 100 feet off the belay with no pro to stop the fall you will fall the 215 feet (the extra 15 feet is from rope stretch, which i think is around 15% or maybe more with dynamic ropes) to find the fall factor you take the distance of the fall (215ft.) devided by the length of the rope (115ft). the fall factor is 1.87. you can get really close to a factor 2, but i dont think you cant factor 2 with any climbing gear. daisy falls can be very close, but daisies stretch a little. maybe if you used a steel cable instead of a rope... also the more slack your belayer gives you the lower the factor is of the fall, because you have more rope out. so if you so if you are 100 feet off the belay and your belayer has 15 of slack out your fall will be 232.25 feet (with stretch). the amount of rope with the stretch is 132.25 feet, fall factor of 1.78. that is why we all like soft catches.

its not like it really matters. climbing is safe.

[Redpoint]

___ I don't think that the Fall factor accounts for stretch in rope. The rope stretch is not as aspect of the fall factor per se. For example a factor 1 fall on a dynamic rope (6% static elongation) is going to have a much lower maximum impact force than a factor 1 fall on a static rope (2% static elongation); even though, these fall factors will be pretty equal. This is the reason we use dynamic ropes.

I was only talking about fall factors, not impact forces, that is sort of changing the subject, but I think it's still on topic since fall factors and impact forces go hand in hand.

I definitely wasn't saying that the fall factor is the only factor in determining impact force. That is a complex equation that involves:

M= rope modulous in ft-lb/sec(squared). Material constant depending on cross-sectional area of rope, fiber, content, etc.

F = fall factor (distance fallen/amount of rope paid out)

m = mass

g = acceleration constant of gravity (32 ft/sec(squared)

I wish I could put the whole equation down but it is so complex I would need to take a picture of it with my camera just to be able to post it on here.

So the M is for the type of rope, and you are correct there.




All I was saying is that when determining the fall distance in a fall factor, I thought it would be after the rope has stretched, not the instant before any stretch was encountered. Of course the amount of static elongation of the rope would play a role in impact force. I would know first hand, I top roped once with a PMI Pitrope, and a fall on one of those even while top roping would send the belayer off the ground as if it was an insane lead fall. I shouldn't have been abusing my PMI Pitrope like that, but I checked the core a lot while doing it and after doing it.

Remember this quote from Mammut that I posted:

"A longer fall with a fall factor of 1, which is not gently braked, can clearly reduce a rope's safety reserve."

Well I guess they are saying as long as you give an excellent dynamic belay with a fall factor 1 fall, the rope's safety reserve might not have been reduced by a whole lot.




This is interesting, my book states:

"Because the rope modulous, mass, and effect of gravity will be constant for any one climber, the maximum force depends on the fall factor. Because fall factor is a ratio of the height fallen to the amount of rope out, this means that the impact force is independent of absolute height of a fall."

FALL SEVERITY:

The severity of a fall is determined by the duration of time that the impact forces must be resisted. Although a long fall and a short fall can have the same fall factor and resulting impact force, the longer fall will be more severe on the falling climber's body and the protection system because the impact force must be resisted for a longer period.

The leaders body, the protection piece holding the fall, and the belay anchor might might sustain impact forces for short periods without damage, but they might not be able to endure these impact forces for greater lengths of time. It makes sense to place intermediate protection pieces to limit fall distance."

So now I know why Mammut said:

"Falls over factor 1, with a fall distance of 5-7 meters, are rated as hard falls."

I guess they are saying that the large 5-7 meter fall would contribute to Fall Severity in a big way when it comes to your rope.




I have never taken Physics, and so I don't have a book for it, but there is always the internet.

p.s. You also forgot to give me the benefit of the doubt for the picture that was second to the left It was definitely a fall factor of 1.

[Redpoint]

oh yeah and you cannot factor 2 on a dynamic rope (or a static rope for that matter, it still stretches 2%). so if you take a fall 100 feet off the belay with no pro to stop the fall you will fall the 215 feet (the extra 15 feet is from rope stretch, which i think is around 15% or maybe more with dynamic ropes) to find the fall factor you take the distance of the fall (215ft.) devided by the length of the rope (115ft). the fall factor is 1.87. you can get really close to a factor 2, but i dont think you cant factor 2 with any climbing gear. daisy falls can be very close, but daisies stretch a little. maybe if you used a steel cable instead of a rope... also the more slack your belayer gives you the lower the factor is of the fall, because you have more rope out. so if you so if you are 100 feet off the belay and your belayer has 15 of slack out your fall will be 232.25 feet (with stretch). the amount of rope with the stretch is 132.25 feet, fall factor of 1.78. that is why we all like soft catches.

its not like it really matters. climbing is safe.

You gave me an epiphany: if every book and pamphlet I ever read concerning fall factors say that 2 is the greatest fall factor, than that must mean the fall factor is factored before the rope stretches. Either that or you are right and there is no such thing as a fall factor of 2 when rock climbing.

Well considering the diagram in my book, I guess it's obvious that their example of a fall factor is before rope stretch:

It shows the climber 3 feet above his last bolt, and when he falls he is 3 feet below his last bolt(a 6 foot fall total), and that just wouldn't be the case if rope stretch was factored in. It also showed a total of 10 feet of rope to the anchor, plus the 3 feet he was above the anchor, which is 13 feet of rope total, and then it gives the math:

6/13 = 0.46




I also just realized that during viaferrata, you could experience a higher fall factor than just 2:

For instance, if you clip a biner in to a wire, and then climb 5 feet above where the bottom of the wire is anchored, and the biner slides up 3 feet above that anchor, and lets say your line attached to that biner is 2 feet long, and then you were to fall, that would have been about a 7 foot fall(because the biner slid down 3 feet, plus the 4 feet drop because of your 2 foot line) with just 2 feet of rope.

7/2 = 3.5(fall factor)

So as you can see, you can experience a much great fall factor during viaferrata than just 2, and so using a dynamic sling couldn't be any more important when doing viaferrata.

Here is an example of what I mean when I was talking about the beaner sliding down the wire:





For anyone who wants to check out the book I am always quoting from, you can read the first 9 chapters for free at google books:

http://books.google.com/books?id=MWtEVQ ... lt#PPP1,M1

I read that the author Jerry Cinnamon has been climbing for 30 years, and I think he was part of the party who first climbed El Cap in one week, the first party to ever do it took them 42 days from what I remember. I also learned from Weather.com's videos that some guy can now do it in a little over 2 hours, but he is free soling for most of it.

[ahab]

do you guys analyze every componet in your automobile with such scrutiny?
this is madness.