WARNING--DMM Dragons, Petzl Strings & Open Slings

Howdy everybody, as I have just purchased a bunch of new 11cm Petzl Express Dogbones and own a bunch of DMM Torque Nuts and Dragon cams, I was thinking of using the old strings I had from retired Dyneema runners to make the DMM slings on the gear mentioned above easier to use. Problem is that you have to pull the right strand to get the slings to extend as the bartacks and plastic sheath don't fit well through the stem of the Dragon cams and Torque nuts. So I just did a quick search on Petzl Strings as they make several versions and one, the String S, is designed for use with Dyneema.

Here's what a String is

Sometimes Google does us BIG favors with weird unforeseen search results, and up popped Billcoe's post on Cascade Climbers last year:

One More Way To Die

For the sake of ease here are the key bits of info from Billcoe's Thread:

UKC Warning Video

Petzl String Warning

Turns out I have been using short OPEN loop DMM Dyneema runners in 11 and 17cm lengths WITH the strings as well of thinking of death rigging my DMM kit.

I liked the open runners as they seemed to be more flexy and thus help keep gear from walking or popping due to rope drag. I just happened to switch to the Petzl Express dogbones as I wanted something easier to clip (with the open loop draws the bottom biners weren't held as well and made clipping a bit trickier). I had actually test rigged my DMM Torque nuts with strings playing around back home but never used them that way.

So...... Just thought I might repost this issue, seems kinda important and perhaps expands the issue to all trad gear with extendable slings, i.e. Wild Country, Trango, DMM to name the biggies. Not to mention reslingsers like Mountain Tools and Yates.

My 2 cents would be to create a bar tacked dog bone with a rubber keeper on one strand of the slings sewn into ALL gear (like ALL dogbones have nowadays), thus forever eliminating the problem.

I emailed links to this to all the abovementioned entities, will post any relevant responses. And kudos to Billcoe for bringing this to our attention.

A friend of mine lost his wife due to an error in using the Petzl String.
register-herald.com/local/x…

Be careful out there.

In the previous thread on bicycle tube DIY retainers I proposed a solution to the open sling issue:

Not sure if the Petzl string would leave enough room for the extra wrap.
Use at your own risk, though.

Wow, thanks for the post! I too had thought about getting a few of these for my open slings, not any more though.

Gregger, just for clarification, you have added another wrap of sling around the carabiner and then cinched it with bicycle tubing (or rubber band) correct? I may have to take a closer look at that technique.

Wehling,
That is correct.

Disclaimer #1 I hardly ever climb sport. SO... Can somebody explain why people keep trying to make this system work when it has such a big downside? Kudos for finding out about the dangers of the string but why are other similar solutions so attractive? To each their own don't get me wrong but I feel like I'm missing something because I don't understand why people don't just walk away from the "string" on an open sling.

I wanted to make it work so that the two DMM Revolvers I have would actually work. They are on the two 48" runners I carry since the longest slings get used at the most critical rope drag placements. The problem is that 50% of the time the 'biner flips over after you climb past it so that the pulley doesn't even touch the rope.
After climbing the past few weeks with these, I think I'll keep the retainers on about half of my slings.

Wannabe wrote:Disclaimer #1 I hardly ever climb sport. SO... Can somebody explain why people keep trying to make this system work when it has such a big downside? Kudos for finding out about the dangers of the string but why are other similar solutions so attractive? To each their own don't get me wrong but I feel like I'm missing something because I don't understand why people don't just walk away from the "string" on an open sling.

I'm not sure what climbing sport has to do with it, but I think that people just don't understand the problem. The woman who died last summer at the New had TWO slings set up like this, and BOTH FAILED at the same time. In her case it was two slings that she used to go in direct to the anchors at the top, so they were already set in in "long position" and not tripled. So she didn't clip the wrong side of the sling while she was pumped, but had it set up that way from the beginning.

That would lead me to believe that it was a systematic error, and that she didn't have it set up properly. I mean what are the odds of BOTH slings getting tangled in her bag or on her harness at the same time?

A lot of my friends were there that day, and knew the family. Many of them have told me that it was not a case of systematic error, but a freak accident. No reason to argue with them.

But I'm like you, I don't understand why people try to do this. If you are really having a problem keeping the biner and sling positioned properly on your anchor sling, there are other ways of remedying the problem. If you are wanting to do this for your tripled draws, that is not what Petzl makes the String for, they clearly state that in their catalogues, and that's all there is too it.

Gregger Man wrote:I wanted to make it work so that the two DMM Revolvers I have would actually work. They are on the two 48" runners I carry since the longest slings get used at the most critical rope drag placements. The problem is that 50% of the time the 'biner flips over after you climb past it so that the pulley doesn't even touch the rope. After climbing the past few weeks with these, I think I'll keep the retainers on about half of my slings.

That does make sense actually and your solution works, but I'm not sure about the double wrap thing. It could potentially load the biner improperly and I'm not sure what it would do to the strength of the sling. I think this would be OK for an anchor sling where you hang statically, but dunno about draws. Probably fine, but I'd be interested to see a pull test.

Why?

For one, some manufacturers still make quickdraw length sewn OPEN runners. I liked those as they had more flop, less chance of trad gear being dislodged or otherwise moved around. But given that they are dyneema and open, they are harder to clip.

My personal experience with any jury rigged band device (and some other brand dogbone draws) is that quite often the damn biner rotates and is held in a cross loaded position. Pretty scary to look twenty feet down and see that.

In the case of DMM Dragon cams and Torque nuts, folks might be tempted to use strings or other bands as one can apparently only extend the sling by unclipping the proper strand. Having a band or string would make unclipping the wrong strand impossible......

Take a look below, the sling bar tacking is also wrapped in plastic, they do the same with the Dragon slings, and the result is that when you want to extend the sling, YOU MUST unclip the non-bar tacked strand, as in the case of both the nut and cam, the bar tacked strand won't fit (at least with human pulls) through either the holes drilled in the hex or the stem of the cam. Many folks have wondered why they did this.

As for long runners, never thought of the Revolver thing, seems true, and it's just nice to see the rope end biner oriented properly.

I can't say I've ever noticed a problem with cross-loading of a carabiner on an extended sling. Maybe it's the shape of the biner? I have D-biners (Metolius infernos) on all my runners. Personally I like tripled open runners for trad climbing, and it's hard to mess up. Works great tripled, and to extend it, all you have to do is completely remove the rope-end carabiner, clip it back around one strand of the runner, and pull. No death-rubber bands on that one.

Ryan Williams wrote: The woman who died last summer at the New had TWO slings set up like this, and BOTH FAILED at the same time. In her case it was two slings that she used to go in direct to the anchors at the top, so they were already set in in "long position" and not tripled. So she didn't clip the wrong side of the sling while she was pumped, but had it set up that way from the beginning. That would lead me to believe that it was a systematic error, and that she didn't have it set up properly.

Yet another reason for this thread.

I have seen that most folks nowadays have the longer trad slings doubled and tripled to be carried on the harness and used as draws AND long runners. A string seems like a recipe for disaster as six of those slings turn into a real tangle, probably very hard to see if its rigged wrong and a lot easier to make the mistake. I just put em over my shoulder and carry a few quickdraws, but not because I knew about this danger.

Quite often I have arrived at an anchor completely pumped out of my mind, so I can see how easy systematic mistakes can be. Seems like lots of folks have fallen at anchors from a variety of relatively simple systematic mistakes.

For my part I had never heard of the possibility of this before today and part of the problem is the string can be removed from old draws and re-used.

Put another way, how many Petzl draws have been sold? That leaves a ton of potential for loose strings. My local gear shop suggested I save my old ones when I bought new draws as the strings are expensive. Said something like they'd be useful for making runners and draws.

Tom Mulholland wrote:I can't say I've ever noticed a problem with cross-loading of a carabiner on an extended sling. Maybe it's the shape of the biner? I have D-biners (Metolius infernos) on all my runners. Personally I like tripled open runners for trad climbing, and it's hard to mess up. Works great tripled, and to extend it, all you have to do is completely remove the rope-end carabiner, clip it back around one strand of the runner, and pull. No death-rubber bands on that one.

Only has happened to me using rubber bands, tape, and a brand of dogbone I honestly can't remember that had a tight loop but no rubber keeper (as almost all modern dogbone draws now have--liability?).

Or you could just use the slings as designed and leave the rubber bands and tape at home. Your choice but it seams obvious really.

I've always used my Revolvers on SHORTER slings. The pulley helped REDUCE the need for a really long runner... I guess you're reducing the rope drag even MORE with that setup...

I'f you're doing that with a 4' sling, a better way might be to use a "rabbit runner" with a String and Revolver on one end. Yates and Metolius make them.

This weekend in the Black, the easy top out pitch on Journey Home had so much rotten rock that at one traverse I combined a 4' and a 2', then did the same about 50' later when I turned the other direction. Rope drag would have been really bad otherwise. - The Revolvers really help.

I keep my revolver clove hitched on a 4' sling. The I triple it alpine style. This leaves me a 1.3 foot QuickDraw. Or I can extend it to 4 feet. The clove keeps it from flopping around and cross loading. You just have to unclip from the other side and it unfolds like a regular alpine draw. Not sure if this will work for those of you that feel the need to have your runners set up this way. Not sure if it's 100% safe either