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[Jeff]

Ropes BREAK during the UIAA tests after absorbing a certain # of EXTREME falls on the same segment over an edge at very close to the same spot on the rope; the failure is usually at the knot.  In ALL climbing rope failures (except some where acid or other chemical contamination was involved) which came to our attention during my 22 year tenure on the UIAA  Safety Commission, the ropes had not BROKEN, but had been CUT-- an important distinction. However, due to the testing on old ropes to which I referred earlier in this thread, I still retire mine to other than lead rope service after a maximum of 5 years use.

It is interesting to see the rope damage suffered in the 100' fall off of the Prow last week, reported elsewhere in this forum. The climber, Hans Bauer, is alive because the rope did not BREAK. I have spoken to a member of the rescue team about that rope and he said the sheath was completely missing from the core strands over about 3 feet of distance and that a number of strands of the core were damaged/severed.

Modern climbing ropes are good and we all know that their WORKING life is much longer than their CLIMBING life; I just want us to be careful not to imply that since 20+ year old ropes still work fine for getting trees to fall where we want them to, they must be still good for climbing-- newbies and young climbers as CHEAP as I once was also frequent this site 

[sneoh]

Ropes BREAK during the UIAA tests after absorbing a certain # of EXTREME falls on the same segment over an edge at very close to the same spot on the rope; the failure is usually at the knot.

Wow, I did not know the failure is usually at the knot.  I would have thought the rope would usually be cut where it contacts the edge.  And if I remember right, the edge is fairly sharp, .i.e., small radius of curvature.  Jeff, do you happen to remember how sharp of an edge is used in the UIAA 80kg drop test for single rope?

Cutting a rope is scray; new (Sterling) rope was cut by a sharp biner in a 0.5 FF or a little hgher fall last year.  Climber survived because he was fairly low to the ground still.

[Jeff]

Yes Sneoh, the UIAA standard edge had an 11 mm radius when I was on the Commission and this edge was also adopted by the CE when the CE adopted the UIAA tests as the standard for PPE ("Personal Protection Equipment for falls from heights" for climbing gear). That was the standard radius in the UIAA Carabiner Standard of the day (I last served on the Commission in 1999-- however I don't believe these figures have changed).

It is true that some ropes failed at the edge during the tests; however the vast majority of ropes which passed the test eventually failed at the knot when tested to failure.

BTW sneoh, the edge is the same, whether testing single ropes with an 80 kg mass or half ropes (AKA double ropes) with a 50 kg mass; "twin ropes" which are meant to always be used and clipped together are tested with an 80kg mass, but together, again over the same edge in the test tower orifice!

A lot of testing was done to try and develop a "sharp edge" test over a sharper radius, but to date the testing difficulties have precluded adding such a test to the standard. These difficulties arise especially since rock edges can resemble a serrated knife blade, and a test edge must have a verifiable polished radius to guarantee consistent and comparable results; it proved easy to define an edge over which no rope would withstand even one drop, but extremely difficult to develop one over which the best ropes would withstand more than one test fall, while the "less good" ropes would fail, in some kind of repeatable and predictable pattern, which is the desired result of product testing.

[sneoh]

Yes Sneoh, the UIAA standard edge had an 11 mm radius when I was on the Commission and this edge was also adopted by the CE when the CE adopted the UIAA tests as the standard for PPE ("Personal Protection Equipment for falls from heights" for climbing gear). That was the standard radius in the UIAA Carabiner Standard of the day (I last served on the Commission in 1999-- however I don't believe these figures have changed).

A lot of testing was done to try and develop a "sharp edge" test over a sharper radius, but to date the testing difficulties have precluded adding such a test to the standard. These difficulties arise especially since rock edges can resemble a serrated knife blade, and a test edge must have a verifiable polished radius to guarantee consistent and comparable results; it proved easy to define an edge over which no rope would withstand even one drop, but extremely difficult to develop one over which the best ropes would withstand more than one test fall, while the "less good" ropes would fail, in some kind of repeatable and predictable pattern, which is the desired result of product testing.

Thanks Jeff for aall this info.
I think, for the 80kg drop test, the radius might have been reduced to 5mm, http://www.theuiaa.org/upload_area/pictorial_files/UIAA101-Dynamic-Mountaineering-Ropes_1.jpg

This seems to make sense since I was playing around with some rather ridiculously light and small biners my friend had yesterday (decided they are not my cup of tea).

I read elsewhere that the UIAA "sharp edge" test is still in development, with argument, as you said, over the size of the 'edge' - 0.75mm, 0.50, even 0.25!!
All pretty interesting stuff to me.

[tradmanclimbz]

The fatal fall from cut rope in seneca a few years ago was also a new rope. What jeff is trying to say about the sharp edge test is that they could not find any ropes that did not cut over a sharp edge and would have had to use a dull edge to do any kind of repetable  test. Run your rope over a sharp edge and you are going to DIE.  

 I have broken  shit ton of rope. While the scientific value of my tests is zero due to not haveing a lab and all kinds of geek shit to regulate and measure with  the real life common sense value of my tests is significant. I have done a boatload of shock load tests where I tie the rope to a BAT (Big Assed Tree) coil 20ft of rope loosely on the  ground, slip a loop over the ball hitch and mosh the hell out of that 300 straight six.   The rope Always breaks at the knott or a sharp edge. The booty Biners Never break and the rope you were too chicken to climb on is almost always totally bombproof..   Unless you have some kind of chemicle contamination the signs of potentual failure will be obvious.
 Any kind of core shot will  fail fairly easily popping away from that spot and slideing up the rope in both directions away from the  break very rapidly leaveing a huge section of core exposed. It is amazeing how strong even one strand of the core is. Enough to hold the weight of the truck on an incline.
 Last year I retired a 2yr old beal 10.2mm because it had a section that felt mushy to me. I posted some shots of that section of rope somewheres.  I did some logging with that rope last summer and broke that section of rope effortlessly.  Other sections of the same rope are pleanty strong and have pulled many big logs.
 I do have a very good feel for how much throttle it takes to break climbing rope. You can realy feel the truck work.  That suspect section broke like butter. almost no resistance.

[sneoh]

Last year I retired a 2yr old beal 10.2mm because it had a section that felt mushy to me. I posted some shots of that section of rope somewheres.  I did some logging with that rope last summer and broke that section of rope effortlessly.  I do wish I had had a way to measure that one. I resistance. Other sections of the same rope are pleanty strong and have pulled many big logs.

Holy crap.  I too have a 10.2 Beal Edlinger II.  It is 4+ years old so I have mostly retired it to TR only.  Both ends have developed mushy sections.  I think I am going to cut the mushy sections off.  Time to go full time on my new 70m 9.9mm!

[tradmanclimbz]

Do the bend test. The section with the sharp bend felt soft and mushy to me. the rope should maintain a natural curve when you bend it. ocasionaly you should feel your entire rope bending it as you go. flat spots and mushy spots and places where the rope does not hold its curve when bending are the end of a rope for me.

This rope I retired instantly when I found this dead spot. I would climb on a 10 year old rope that looked and feel good as long as I know it has not had  contact with bad chemicles.

[tradmanclimbz]

Additionaly. that suspect section of rope broke in the middle of the  line between the log and the truck. Not at a knott or sharp edge.  That is super rare and only seems to happen to rope that has been seriously abused and has damaged sections outside of the knots.

[sneoh]

Thank you very much, Nick.  I will do the bend test on the Beal 10.2 before I go climbing with it again.

[Jeff]

Thanks Jeff for aall this info.
I think, for the 80kg drop test, the radius might have been reduced to 5mm, http://www.theuiaa.org/upload_area/pictorial_files/UIAA101-Dynamic-Mountaineering-Ropes_1.jpg

This seems to make sense since I was playing around with some rather ridiculously light and small biners my friend had yesterday (decided they are not my cup of tea).

I read elsewhere that the UIAA "sharp edge" test is still in development, with argument, as you said, over the size of the 'edge' - 0.75mm, 0.50, even 0.25!!
All pretty interesting stuff to me.

Sneoh, of course you're right about the radius! It hasn't been changed-- I just misspoke from memory-- the edge was designed to represent a carabiner and the standard bar stock for carabiners was 10mm DIAMETER so the radius of the test edge was set at 5 mm. Now that lots of different shaped biners have been developed, with sections cut out to reduce mass in unnecessary areas, forged H shaped bars, etc, you'll note that they still take care to keep the rope bearing surface @ a 5 mm radius.

As for the "sharp edge" test still being in development, what you read about those tiny edges being discussed I remember well. The hunt will continue, but the properties of the yarns used in ropes, and the other parameters of weight, hand, knotability, etc. place such limitations on the development of a rope which won't cut, that I don't believe we'll see one while I'm still climbing.

 Perhaps you remember the short lived ad which appeared in all the climbing mags of the day back in the late 80s I believe. Edelweiss had a rope which they were touting as having passed an in house "sharp edge" test over a narrower radius than the UIAA standard-- unfortunately for them, an eager advertising department had produced a photo of the rope passing over a sharply acute angled and toothy granite edge which looked like a serrated knife: exactly what no climber would ever allow to happen to his/her rope if he/she could in any way avoid it. At our Commission meeting in Chamonix that year, the other rope manufacturers brought copies of the ad in question and asked that it be withdrawn as false advertising. Otherwise they offered to pay to have the test done as pictured. The penalties attached to European and British truth in advertising laws were  (undoubtedly still are) severe enough that apologies were offered, a zealous PR guy ignorant of real life climbing was blamed, and the ad was withdrawn immediately-- it did not appear in the mags even the next month.

[Jeff]

Re: Nick's "bend test"-- I totally agree! I retired an 8.8mm half rope this summer which I have used on ice and rock for about 30 days over 3 years because I found a "mushy" spot as Nick describes at about the 80 foot mark; I don't know if it was damaged while rappelling over an edge (no sheath damage visible) was kicked too hard while ice climbing, or had something fall on it. I was running it through my hands to check it and felt the soft spot-- I did the bend test which Nick pictured in his photo, saw the same configuration and took it out of service. I then checked its  8.8mm partner and found it to have no "worry" areas, so I'll continue to use it as a 2nd rope when I want a rap line, but am climbing on a single rope.

[strandman]

Beal's still get mushy spots They did years ago as well and fluffed up nice as well. 

As for edge cutting- at least we don't still have those terrible Stratos ropes anymore.

[Jeff]

Ah yes, the Stratos-- that was the rope in the misleading sharp edge test ad!

[tradmanclimbz]

Metelious marketed a super safe rope about 10years ago? supposed to be cut resistant but they seem to have backed off on that?

[Jeff]

I'm quite sure Metolious has never manufactured ropes-- I don't know which manufacturer was making them for them-- for a long while Black Diamond ropes were made by Beal, but I don't know who makes them at the moment. Cut resistant is the toughest parameter to achieve, esp. with the current tendency to move to thinner, lighter ropes-- less mass in the rope makes it easier to cut through, as one would expect. You must decide which trade off you are willing to accept, and place your protection accordingly. Avoiding sharp edges and flakes is key!