fell at 1st bolt = core shot...

I fell 6 feet, with probably 12' of rope out, aka onto the first bolt.

I was back-clipped. Rope core showing and rope section is molded into shape of carabiner...

Not sure if back-clipping led to 'coring' vs what a correct clip would have resulted in (nothing?).

It held, I'm happy, no complaints, just sharing.

Teachable moment = always scope your rope after a fall...

(Rope is 9.9mm New England Galaxy, 2 yrs old but little used.)

6 ft fall with 12 ft of rope out = core shot.

So, do you back clip a lot? Seems like you got off easy considering...

How about a worn carabiner?

Worn Biner

Worn Biner

Eep. That's a scary photo. I have no clue how backclipping would have resulted in that. I'm usually a fan of New England ropes. I took a 20 foot whipper, pretty much static because of belayer communication issues, in Clear Creek with my older Glider and the worst that happened was that the core got sucked in a bit.

I'd e-mail New England and include that photo. Who knows. Glad you're OK though!

Thats the third one of those ropes I've seen the same problem with. They have those single pic sheaths. I am no materials engineer, but the sheaths seem really tight over the core. They have a very strange hand and you can feel how difficult it is to bend them over a small radius. I saw one get core shot on a short fall on a new biner and the other shot when it was pulled off the anchors of a top rope(!?). Both were situations where I never would have expected a core shot.

There is something up with the way those ropes were put together. Ropes shouldn't get core shots so easily. Contact New England.

Not a worn biner issue as core shot was top of bend. The rope is 'stuck' in bent over position as photographed.

I try not to back-clip, and did not realize I did until I looked at how the rope was now bent, knowing my belayer was to my right...

One thing to consider is that even though you only fell 6', because there was only 12' of rope out the fall factor, which measures the stress on the rope, was .5. If you'd fallen 50 feet with 100 feet of rope out, it'd put the same load on the rope, since more rope means more stretch/shock absorption.

My other thought was that since you fell near the end of the rope, maybe the rope had been stressed more from 2 years of knotting and unknotting? Hang-dogging at the first bolt? 12' from the end is kinda far, but I know people sometimes cut the ends of their rope since the section that gets tied takes a lot of stress.

Was the belayer using a gri-gri? In his anchors book John Long likes to mention that ATCs, Reversos, and the like limit the load to 2-3kn at any given instant since they actually slip a little and distribute the load over time. Gri-gris lock up and absorb much less force.

Having been back-clipped...it's possible when you fell the rope was twisted against sharp rock before taking the full load, weakening the (thin or poorly made?) sheath and then the final impact forced the core through this section of the rope.

You "try" not to back clip? How about you just don't do it? Shouldn't your belayer also be paying attention and tell you as well? Looks like the twist in the rope from backclipping played a part in the coreshot. Go back and check the biner...a small amount of flat wear can result in a pretty easy coreshot.

Being an old traddie who only owns 10.2 or above, does anybody think that the newer use of 9-somethings is part of the problem? So many slim and tall guys only weigh like 155 or less and that might be OK to go the 9 route. Being anything over 180lbs, I would still want to use my 'fat' ropes for all things leading.

I very strongly believe in New England Ropes. That is not to make light of this, but I feel it should be stated that they are one of the most dependable ropes out there. I factored two-ed on a retired 9.8 while rope soloing... over cammed the gri gri.... the rope held (or I would not be here.

All the possibilities are there for why this happened. I would say that though I believe in the manufacturer, I DO NOT believe in the design of the newer ropes. As far as i can tell, nylon is still nylon, but they have managed to get the things lighter and lighter over the last few years. This is in design obviously. And I believe they are sacrificing strength in the long term for a rope that passes the tests right out of the bag and is lighter.

So, I climb on a slightly heavier rope almost all the time. I save weight by using the lighter biners, lighter harness, and taking bigger shits in the morning.

So a bit more info, this was the 1st lead fall on this rope, which ahd at most 5 days of outings on it. The biner I fell on was mine and had NO wear/grooving and was a standard sized biner. I bought the rope at REI with a 20% off coupon and it was the only 70 bi-color they had, which is what I wanted...

The blowing apart of the sheath is likely b/c I was back-clipped, causing a already kinky rope to kink a bit more as I fell and the kink ended up at the biner and blew out. The core shot is 3 ft from the KNOT. And I weigh 135 lbs. *I* do not consider this to be a skinny rope as I usually use a 9.2 Beal joker which I really like.

I cut the core shot off and will happily and without worry use this rope. I have no interest in contacting the manufacurer. But I will be very careful not to back-clip any more. AND I WILL ALWAYS CHECK MY ROPE AFTER A FALL....

Thanks for the discussion. (edited to fix 3' from end to 3' from knot.)

Woodchuck ATC wrote:Being an old traddie who only owns 10.2 or above, does anybody think that the newer use of 9-somethings is part of the problem? So many slim and tall guys only weigh like 155 or less and that might be OK to go the 9 route. Being anything over 180lbs, I would still want to use my 'fat' ropes for all things leading.

I dunno. I'm 175-180, have taken plenty of fairly big falls on sub-10mm ropes, and haven't had any core shots.

I wonder about the length of the rope out. I know that a 6' fall on 12' of rope creates the same FF as a 50' fall on 100' of rope. But, with only 12' of rope out, all of that force is absorbed by a relatively short amount of rope. Is it possible that has something to do with it?

There is a good chance the rope ran across the nose of the biner, since it was back clipped. This might explain the core shot. The poster is lucky the rope didn't unclip from the draw.

Crag Dweller wrote: I dunno. I'm 175-180, have taken plenty of fairly big falls on sub-10mm ropes, and haven't had any core shots. I wonder about the length of the rope out. I know that a 6' fall on 12' of rope creates the same FF as a 50' fall on 100' of rope. But, with only 12' of rope out, all of that force is absorbed by a relatively short amount of rope. Is it possible that has something to do with it?

That is the whole point of fall factors.

Guy H. wrote:There is a good chance the rope ran across the nose of the biner, since it was back clipped. This might explain the core shot. The poster is lucky the rope didn't unclip from the draw.

That's what I thought too: that the rope snagged on the gate or nose as it was unclipping. If so, you're very lucky it snagged and suffered a core shot, and didn't unclip -- replacing the rope will cost you much less than the medical bills would have cost you.

The core shot is 3 ft from the end of the rope.</quote

3 Feet?! If I'm reading the situation right, that would have put the core shot within a foot of the tie in knot when you were tied in. I doubt that the carabiner/gate was exerting much, if any, force on that part of the rope during the fall(unless your total fall distance was ~ 1 foot).

My bad, the core shot was 3 ft from the knot. I edited the post..

Interesting scenario about the rope 'attempting' to unclip, and scraping the biner nose resulting in the sheath being cut.

I can totally see that happening, and looking at the pic of how the dark shealth strands are standing straight up, like an eyebrow(!) looks cut...

And yes, I AM LUCKY that it did not unclip.

cheers

JohnWesely wrote: That is the whole point of fall factors.

Fall factor is one component in the equation but there's more to it than that.

Impact force is what is really in question here. And, to keep it simple, fall factor is the amount by which the force generated by the fall is multiplied to create the impact force. So, while two different falls may have the same fall factor, they may generate very different impact forces.

Keeping the FF constant, a fall on a shorter length of rope will generate a greater impact force than a fall on a longer length of rope.

Crag Dweller wrote: Fall factor is one component in the equation but there's more to it than that. Impact force is what is really in question here. And, to keep it simple, fall factor is the amount by which the force generated by the fall is multiplied to create the impact force. So, while two different falls may have the same fall factor, they may generate very different impact forces. Keeping the FF constant, a fall on a shorter length of rope will generate a greater impact force than a fall on a longer length of rope.

Care to share how you are coming up with these numbers?

I know this post hasn't seen a lot of traffic, but it had me curious about the terminology we're using so I thought I would consult my closest climbing book and see what it had to say.

Heidi Pesterfield's "Intro to Traditional Climbing" says that for falls with the same fall factor, lab tests and theory show that the same impact force will result. Impact force being the maximum force applied to the system (rope, protection, belayers, etc).

Impact impulse (I think most people just call it impulse), refers to the force and the length of time that force is applied to the system.

For our physics minded folks, our max impact force is simply (mass * max acceleration). Impulse is (max force * change in time). You'll notice impulse can also be expressed as (change in velocity * mass) which is change in momentum.

Pesterfield says that for a ten foot fall on twenty feet of rope, the impact force would be the same as a fifty foot fall on one hundred feet of rope. The impulse of the longer fall, however, would be a larger value than the smaller fall. Stress on the system as a whole would be greater in the second fall.

I make no claims to be an expert in the forces at play in climbing, this is simply paraphrased from Pesterfield's text.