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PostPosted: Wed Nov 30, 2005 2:05 pm 
Hi,
I was wondering if anyone can explain the number of falls on a rope to me... mammut suggests that my type of rope was tested and held 12 falls of 80kgs and then failed .... I can understand that that was probably at a fall factor above 1.77.....

Okay this is what is worring me , I have winged it a number of times and this kind of info is concerning as i know not to what degree my rope has been beaten up...


can someone please help me understand fall factors and what ropes can endure... ???


help :(


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PostPosted: Wed Nov 30, 2005 3:34 pm 
typically a rope is rated for facor two falls. THere is no way you have taken many of those. A fall factor is the length of fall div by number of pieces of pro... etc. It gets pretty complex but basically it is possible to take really huge low factor falls. The only time to worry is if you fall with no gear directly below your belayer as that is a big impact fall.


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PostPosted: Wed Nov 30, 2005 4:38 pm 
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Joined: Mon May 23, 2005 5:30 pm
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Location: Cape Town
Real Name: Jonathan Joseph
Have had my 10.5 Edilweis (?sp) for going on six years now, and have taken countless sub-factor2 falls (and maybe one factor2 - not 100% sure, but it was a blerry long fall).

Still have good faith in my fat cable! Not sure how my partners feel though.
:twisted:


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PostPosted: Wed Nov 30, 2005 5:00 pm 
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Thanks for the warning! :wink:

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PostPosted: Wed Nov 30, 2005 5:30 pm 
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Location: Joburg
Fall factor = the legth of the fall divided by the lenth of rope (from belayer to climber)

So if you climb past your belayer, clip after 1m and then fall after 1 more m, you fall 2 m down (1m to your last clip and 1 more m of slack rope) and the length of your fall is 2m. 2/2 = FF of 1.
If you climb past the belayer, clip after 2m and then fall after another 1m, you fall 2m but the rope length is 3m. 2/3 = FF of 0.66.
If you climb past your belayer, don't manage to clip and then fall when you are 2m past the belayer, the length of the fall is 4m, the length of rope is 2m. 4/2 = FF of 2.

Try to clip before you fall :D

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PostPosted: Tue Dec 06, 2005 12:38 pm 
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Location: South Africa
Fall Factor
Total height of fall /length of rope used = Fall factor
Fall factor must always be under 2 !


1

Height of fall 5 m
------------------------- = Factor 2 => DANGER
Lenght of rope 2,5 m



Image


2

Height of fall 5 m
-------------------------- = Factor 1 => OK
Lenght of rope 5 m

Image


Taken from edelweiss ropes.

Remember, always try place pro as soon as possible, 'big balls gets you hurt, clever big balls makes for a rush'

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Last edited by timmy on Fri Dec 09, 2005 3:35 pm, edited 1 time in total.

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PostPosted: Fri Dec 09, 2005 11:08 am 
If you climb up to a roof past your belayer without placing any gear, and then hang upside down on a jug in the roof and propel yourself as hard as you can downwards with your legs (jumping upside down), you can produce a factor fall that exceeds factor 2. I recommend using a backup rope if youve got strong legs, but it would be cool to try see if you cold snap a brand new rope this way.


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PostPosted: Sun Dec 11, 2005 7:03 pm 
The standard UIAA fall is 5m with a fall factor of 1.78. So it is a very severe fall. See the entry above for an explanation of fall factors.

In addition, the fall test is with a dead-weight (not a human being), and with a completely static belay. In a normal climbing fall - even one with the severe parameters of the UIAA test (5m at fall factor 1.78), a lot of energy is absorbed in other parts of the system (not just by the rope). For example the climber herself - a viscous mass of blood and bones - will absorb part of the energy of the fall in her own body. The belayer too: assuming the fall is held ultimately by the weight of the belayer, and not the gear.

With the fall being held by such a short length of rope, I think one would find that the energy absorption by climber and belayer make a huge difference, and the number of falls would be many more than 12. And in any case, if you even just take one UIAA fall whilst climbing, you're bloody crazy.


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PostPosted: Tue Dec 13, 2005 8:24 am 
My worst fall, which also happened to be my first, was a factor 2 fall. We paid very close attention to all three pieces on the stance. Made sure that they were all share loaded correctly. It was a the kind of stance you would see in a text book on climbing…except for one thing…
I had placed two pieces of gear just above the stance (I knew they weren’t the greatest :oops: ) got passed them and fell. Along with me came my first 2 pieces kit, sending me flying past my belayer. This is where our mistake came into affect. We had left some slack in the stance and as I was plummeting downwards and I yanked my belayer of his feet and slightly over the edge. And both of bodies (mine being 91kg’s and his between 75 and 80) came to a very sudden halt directly onto our stance. Good thing the stance held just fine. I still feel that the ropes did squat in terms of absorbing the energy of that fall. I’m not saying that ropes don’t stretch, just that there wasn’t enough rope to absorb the energy of my fall. My body however did stretch, especially my back, it ached for weeks after. Needles to say I chopped the first five meters of both the ropes. It isn’t worth the risk.

Also remember this:
When taking big falls, even if there is 20m of rope between you and your belay. In effect only the closest couple of meters to you will be able to absorb the fall. The biggest determining factor of this will be rope drag. This is explained very well in the Beal catalog on the last few pages. Do yourselves a favor and try to get hold of one, Petzl also has loads of good info in the back of there’s.

The scariest thing about sport…you only got one rope to catch you…what if it’s dodgy… :shock:

fanta


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PostPosted: Fri Feb 08, 2008 4:16 pm 
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Hi, I'm trying to get my head around this because I'm quite new to climbing... Is the \"length of rope used\" the total length of rope between you and the belayer?
When would this kind of fall happen? From the pictures it looks like multi pitch routes because the belayer is not standing on the ground... Is it likely that you could experience this kind of fall is normal sport climbing assuming you clip at each bolt?


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PostPosted: Fri Feb 08, 2008 4:25 pm 
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Yip: \"length of rope used\" = the total length of rope between you and the belayer

Yeah man, factor 2'ing on a multipitch sport route is entirely possible if you fall before clipping anything past the belay, but the ground will stop you before you get to factor 2 on a single pitch sport route and your belayer is standing on the ground.

Ir is however possible to get more than a factor 1 fall, even if you clip each bolt. Check out: http://en.wikipedia.org/wiki/Fall_factor (short explanation) and this better one: http://www.southeastclimbing.com/faq/faq_fall_factor.htm

One other thing to keep in mind: Worry more about YOU breaking than the rope - anything above factor 1 can get uncomfortable.


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PostPosted: Tue Feb 19, 2008 11:00 pm 
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Just remember this: The test falls represent an extreme situation designed to measure the effectivity of the rope in a quantifiable manner.
Climbers do not fall like that in practice.
Climbing ropes cannot break. They can be cut very easily. They can be chewed through in no time by chemicals. But they cannot break. OK, two tractors pulling in opposite directions aside, but a falling body will never break a climbing rope.
What you need to check for is wear on the rope. If you've taken a fall, and the rope is not cut through the mantle, the rope will still be fine. I have ropes that are older than some people on this forum (well, almost), and they are still holding falls (and I weigh more now than I did back when those ropes were new!).


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PostPosted: Wed Feb 20, 2008 12:11 pm 
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As noki said, the issue is not the rope breaking but there is a serious issue he missed here. With an old rope that has lost its elasticity the strain on the climber and belayer when taking a fall as described by fanta in this post is the big issue. Fanta already said he felt like his rope had no stretch. I bet it did and imagine what would have happened if it didn't.

If you fall 5m on a piece of effectively static cord you are likely to break something even if your anchors are bomber. The other issue is the less than bomber gear. A cord with no stretch is more likely to rip it out than one with some stretch to absorb the impact.


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PostPosted: Wed Feb 20, 2008 4:55 pm 
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If I remember correctly - UIAA rated falls are also over an edge of a specified diameter - which is quite small - not quite a blade but certainly a sharp edge.

In a clinical environment it is nigh on impossible to break a rope. It's the edges and abrasion damage that is probably 80% of the concern.

Exiting the realm of science and entering personal opinion now:
If you're taking less than factor one falls without any abrasion/edges involved - your rope will last ages. After a hard fall it does take approx 15 mins for the rope-fibres to retract - ie taking many large jumps on it in very close succession will take life out of it. (solution - if you want to take wingers in close succession without rests then swap sides of the rope)


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PostPosted: Wed Feb 20, 2008 6:58 pm 
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@ant Where did you find out about the 15min rope flex thing and what would a hard fall be?


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