Two Ropes - One Croll

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Two Ropes - One Croll

Postby jharman2 » Jan 19, 2013 10:56 am

Last weekend I was climbing a 35' pitch rigged with 11mm PMI with my standard frog rig. Let me take a moment to describe my "standard" frog rig.

ABC upper ascender
Petzl Croll
Petzl Super Avanti Harness
Screw lock D-ring
Petzl Torse chest harness
Petzl Pantin
9.4mm dynamic tied cowstail (barrel knots on the biners) about 2" of tail hanging free from the barrel knot
Long cowstail connected to ABC upper ascender

I got about 3 strokes off the deck and the 2" tail on the cowstail barrel knot became co-located with the mainline in the croll. It was jammed so hard that I couldn't thumb the croll down or (easily) open it. I was also unable to fully stand up in my footloop because the upper ascender was now basically stuck 1" above the croll. I was for all intents and purposes, stuck on rope.

I rectified the situation by tying a butterfly knot below the croll, and clipping into it with my short cowstail. Then I was able to stand on a natural ledge, fully unweighting the croll. After a minute or so of playing around I was able to open the cam and remove both ropes.

Obviously, I was a buffoon for not securing the loose tail of the barrel knot. Had it been taped to the cowstail it would not have been able to get into the croll. I'm posting this as a cautionary tale for other folks using tied cowstails. Had this happened in a less forgiving situation, like a waterfall, the outcome could have been much different.
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Re: Two Ropes - One Croll

Postby gindling » Jan 19, 2013 11:07 am

I have had the same thing happen though it was with 9mm static line and 10.5mm dynamic. Thats when I started zip-tying my free ends of my cowstails with two zip-ties each. I found duct tape to eventually come off especially in wet or very humid areas. Good thinking with the alpine butterfly.
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Re: Two Ropes - One Croll

Postby jharman2 » Jan 19, 2013 11:14 am

gindling wrote:I have had the same thing happen though it was with 9mm static line and 10.5mm dynamic. Thats when I started zip-tying my free ends of my cowstails with two zip-ties each. I found duct tape to eventually come off especially in wet or very humid areas. Good thinking with the alpine butterfly.


Per another post I just made, I was running 9.4mm dynamic on my cowstail - which would give about the same amount of free space in the croll as your 9mm static and 10.5mm dynamic.

You're right, tape probably isn't the most elegant solution. Zip ties or shrink tube would be better.
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Re: Two Ropes - One Croll

Postby Scott McCrea » Jan 19, 2013 7:46 pm

I throw caution to the wind and use short tails on my barrel knots. About 3/4". Of course, I do melt a globulous mushroom-head on the end that will theoretically jam in the knot and save my life. I have also played around with stitching the tail to the main--just thru the sheath. It seems to work well, but I prefer the short tails.

IMO, tails on knots provide a level of safety, but short, small, clean, neat, tidy knots may be safer, as they tend to not cause problems.
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Re: Two Ropes - One Croll

Postby cavedoc » Jan 21, 2013 3:19 pm

Thanks for posting this. It's a good cautionary tale. I'm glad you had a ledge to transfer to. In free space it would have been a lot harder to fix. Long tails (and yours weren't particulary long) provide a degree of security but this is a great example of unintended consequences. Sometimes reflexive redundancy can do more harm than good.

If you had been free hanging, how do you think you would have gotten out of that jam?
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Re: Two Ropes - One Croll

Postby PeterFJohnson » Jan 22, 2013 12:50 am

This is pretty similar to a situation I ran into once. The only difference was that a nano style biner "colocated" in the croll as opposed to the tail of the knot. John Harman(pantin apologist) happened to be there when it happened to me. So I think the logical conclusion is that this problem is caused by caving with John Harman or being John Harman.

I also tied into the rope with a butterfly and then stepped up on a ledge to take some of my weight off the croll. I remember it being a bit sporting. But the back up plan - had I been hanging in mid air - would have been to tie a 2nd butterfly below me and then step up in the loop of the butterfly.
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Re: Two Ropes - One Croll

Postby jharman2 » Jan 23, 2013 3:54 pm

cavedoc wrote:If you had been free hanging, how do you think you would have gotten out of that jam?


I think I would have gotten out my extra ascender, attached it above my upper ascender, transferred my foot loop to the extra ascender and tried to stand up and fiddle with the Croll. Would it have worked? I don't know.

PeterFJohnson wrote:This is pretty similar to a situation I ran into once. The only difference was that a nano style biner "colocated" in the croll as opposed to the tail of the knot. John Harman(pantin apologist) happened to be there when it happened to me. So I think the logical conclusion is that this problem is caused by caving with John Harman or being John Harman.

I also tied into the rope with a butterfly and then stepped up on a ledge to take some of my weight off the croll. I remember it being a bit sporting. But the back up plan - had I been hanging in mid air - would have been to tie a 2nd butterfly below me and then step up in the loop of the butterfly.


I remember this! After that happened to you Pete, I always make sure I clip my footloop biner AWAY from the croll.

You are obviously correct, the problem is being in proximity to me. Of course, I am in the unfortunate situation of always being in proximity to me. I should probably just stop caving to prevent this from happening again!
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Re: Two Ropes - One Croll

Postby Scott McCrea » Jan 23, 2013 4:02 pm

jharman2 wrote:[I think I would have gotten out my extra ascender, attached it above my upper ascender, transferred my foot loop to the extra ascender and tried to stand up and fiddle with the Croll. Would it have worked? I don't know.

Only one way to find out. Try it. In a controlled environment--maybe inches off the floor or next to a ladder.
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Re: Two Ropes - One Croll

Postby John Lovaas » Jan 23, 2013 4:16 pm

I've had 2 experiences of stuff getting dragged into the Croll- my footloop tether, when I was still using webbing for that purpose, and a section of my upper cowstail, when I was using 8mm static for my cowstails. Both incidents occurred when the system was completely slack and I began the stand part of the cycle.

Both times, I rigged an ascender above my Croll and positioned the upper so that I could stand up in the footloop(and wrap my 'ascender arm' around the lifeline) and fiddle with the Croll. Wasn't much more energy intensive than a changeover. My 3rd ascender always has a webbing tether with footloop attached.

I'm also more vigilant now about how everything 'lays' on my chest and belly when the system is slack. I use 10mm dynamic for my cowstails now, and the skinny little Petzl footloop- so I feel I always need to be watchful. 'Keeping my eyes on the road'... ;-)
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Re: Two Ropes - One Croll

Postby Scott McCrea » Jan 23, 2013 4:29 pm

FWIW, I have never had this happen with a my Texas system. :nana:
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Re: Two Ropes - One Croll

Postby Mike Hopley » Jan 28, 2013 6:13 am

It's really annoying when this sort of thing happens!

Keeping the rope ends short is good, but your 2-inch tails are pretty short already. I reckon 1 inch is a reasonable minimum (I prefer about 1.5 inches). It's essential that the knot is body-weight tightened on both sides before cutting tails short.

Securing the ends solves the problem, but also makes the cowstail ends more rigid; I don't like this.

Whatever you do, the problem won't completely go away. There is always something that will occasionally feed into your Croll. If it's not your cowstail, it's your footloop, or the end of your chest tape, or a bungee cord. It's good to be familiar with unweighting the Croll in these difficult situations.
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Re: Two Ropes - One Croll

Postby paul » Jan 28, 2013 7:11 am

Another issue to throw in on cowstails and tails on knots: Bob Mehew of the Bristish Caving Association (who has done various tests on knots and breaking strength) recommend re-tying (and again tightening the knots using body weight) knots on cowstails after any fall in order to loosen the knot as the tightening of the knot in the fall plays a part in absorbing shock.

Having tightened your cowstail knot and then trimmed the tail to a very short length, that would make this a bit difficult.
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Re: Two Ropes - One Croll

Postby Jeff Bartlett » Jan 28, 2013 10:53 am

I'm very curious if the new Petzl Croll -- with a smaller rope channel, corresponding to the decrease from 8-13mm rope to 8-11mm rope -- eliminates, or at least mitigates, this issue. I just don't see how much else can fit in there with an 11mm rope loaded.
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Re: Two Ropes - One Croll

Postby driggs » Jan 28, 2013 4:27 pm

Jeff Bartlett wrote:I'm very curious if the new Petzl Croll -- with a smaller rope channel, corresponding to the decrease from 8-13mm rope to 8-11mm rope -- eliminates, or at least mitigates, this issue. I just don't see how much else can fit in there with an 11mm rope loaded.


Or will the smaller rope channel make it more difficult to get un-stuck when a 6mm pack tether, a webbing footstrap, or a 3mm dyneema footcord gets eaten?

If only someone had one of these mythical new ascenders and could answer this question for us...
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Re: Two Ropes - One Croll

Postby Jeff Bartlett » Jan 28, 2013 4:35 pm

driggs wrote:Or will the smaller rope channel make it more difficult to get un-stuck when a 6mm pack tether, a webbing footstrap, or a 3mm dyneema footcord gets eaten?

If only someone had one of these mythical new ascenders and could answer this question for us...


First chance I get, I'll drape my body with 5mm cord, 6mm cord, 1/2" webbing, 1" webbing, shoelaces and cheerleader pom-poms, then kit up and go thrash around on rope until I get myself stuck. I don't have any 3mm dyneema, though, you'll have to provide a lengthy spool of it for sampling purposes.
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