French Wrap Self-Belay

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Postby hunter » Nov 28, 2005 11:51 am

Hey Robert,
Thanks for the well written post with good references! The top roping article made interesting, and slightly scary, reading.

James Hunter
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Postby NZcaver » Dec 3, 2005 1:14 am

RescueMan wrote:Gary was refering in that article to the old prusik-above method which has been widely discredited ... What this thread has been about is the "French Wrap", more commonly called the autoblock, below the descender.


Your comment about Gary's article is mostly true, but not entirely. He does say...

One alternative that seems better than the chest Prusik (but still not adequate to me) was presented by Larry Penberthy in Off Belay No. 16, pp. 10-11. Since "The trouble with the chest/Prusik system is that a beginner [anyone - gds] may lose control, start to slide rapidly, panic and then grasp the Prusik even tighter, thus preventing it from working. It is contrary to instinct to let go of the rope to gain security". So, "At an MSR 'working' field trip, we devised a new method of security for rappel

The rope from above passes through a [rappel device] and then down to a security knot [Mr. Penberthy recommends either a Penberthy or a Penberthy-Pierson knot, not a Prusik - gds] attached to a webbing loop around one thigh [nowadays, attach to the harness - gds]. When descending normally, the braking (lower) hand grips the knot to prevent it from grabbing, and simultaneously applies enough friction to control the rate of descent.

"As the climber descends, the rope slides upwards through the security knot, and then through the friction device. If the climber lets go with his braking hand completely, the knot grabs and stops him. If he grips the control knot tightly in panic, the extra braking friction force stops him, assuming the friction device has a high enough friction ratio."

But there is a problem, and Mr. Penberthy recognized it: "CAUTION: The security knot must not be able to touch the [rappel device]. If it does, the security knot will not grab". My experience suggests that this disadvantage is enough to be a problem, so I do not use this technique.


Gary doesn't specifically describe this as a French Wrap, but it's the same basic idea. Thank you for posting the link to Brady Robinson's article, it makes interesting reading. I was just 'stirring the pot' when I suggested such things should be universally rejected among cavers. My bad. :wink: I agree with you that the French Wrap technique has its own limitations and caveats. I feel it is up to each individual to make his or her own informed choice about this.

Rescueman wrote:As for those of you who claim to dislike the autoblock safety while admitting to having never tried it, isn't that a bit like thinking sex is gross before ever having enjoyed its benefits?


Quite. If you were referring to me with that comment, you misunderstood. I said "I have toyed with setting up a rappel safety once or twice myself - but I've never seriously considered actually using one." This means I've tried it, on rope, for real - but personally its cons outweighed the pros for me. I like the KISS principle, and I don't feel a separate rappel safety fits into my definition of that. But if others choose to use the French Wrap as a rappel safety, more power to them! :grin:

Great rope info and links, by the way. Keep up the good discussion! 8)
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French Wrap

Postby cavegrrl » Dec 14, 2005 8:06 pm

I see that I'm coming into this discussion a little late, but I can't help myself.

I have been using the FW for a year now. I practiced with it in a tree quite a bit before I ever used it in a pit. But then again I did a lot of practice in a tree learning how to change over and use my rack before I ever did that in a pit. I have also hung upside down from it. Personally, I would rather hang upside down, be uncomfortable and have to worry about harness hang while my caving buddies come and get me than to be laying in the bottom of a pit not having to worry about harness hang because I'm severely injured or dead waiting for my caving buddies to come and get me. Of course I know that my caving buddies can come and get me. :) I can also recover from hanging upside down if I'm concious. I use it all the time now since I don't know when that one time is that I may need it.

I especially like it for long drops. Bridge Day this year was the longest drop I've used it on yet. I needed to drop bars and then part way down add bars and had no problem doing this with the FW. Nor do I have a problem rappelling with the rope between my legs with the FW. When the prusik loop is adjusted properly and you've worked with it enough it is not only efficient, but very simple to use. One small extra step of wrapping the loop around the rope and clipping it into the biner becomes muscle memory very quickly, just as anything else we do vertical when practiced.

I have never run into an issue with the wrap going up into my rack and have found this to be the most simple form of self belay that actually works, is easy to use and is extremely easy to manipulate.

If you are vertical long enough sooner or later your going to run into some sort of problem and no one knows when that will occur or what that problem will be. I've been vertical 10 years and in the last year I had a situation on rope myslef, a good friend of mine was hit by a rock (he was on top belay), and I had a friend who dropped just before me on a long rappel unable to add his bar back on part way down and he came crashing into his bottom belay. No one was injured but he stated that the next time I see him he will be using a French Wrap. I would like to make choices that help keep any situation I run into just that, a situation and not an incident. For me using the French Wrap is one of those choices.

:bat:
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Re: French Wrap

Postby NZcaver » Dec 14, 2005 10:41 pm

cavegrrl wrote:...Personally, I would rather hang upside down, be uncomfortable and have to worry about harness hang while my caving buddies come and get me than to be laying in the bottom of a pit not having to worry about harness hang because I'm severely injured or dead waiting for my caving buddies to come and get me... :bat:


Cavegrrl - no argument there! :grin:

Personally it's not the actual function of the French Wrap that I dislike - just the mechanics of the FW itself. The FW is probably most useful with a rack, just as you described. However some of us don't often use racks - my ones usually only come out of the bag when I'm teaching others the basics.

I think I mentioned this in a previous post, but I prefer to use an auto-stop descender like the Petz or SRTE Stops, or a true controlled rate descender like the Troll Allp. Using these descenders a FW becomes totally redundant, and an unnecessary hindrance. If you find yourself suddenly rendered unconscious, an auto-stop descender stops you the same way the FW *should* - but without a significant portion of the load ending up on one thigh. A CRD like the Allp won't actually stop you if you go "hands off", but if you have it pre-adjusted correctly you should just descend gracefully to the bottom of the pitch - *theoretically* making a rescue that much easier (no pick-off required). :wink:

It's true that auto-stops, bobbins, etc are not as synonymous with very long drops as the rack is - so it sounds like you have chosen the best setup for yourself at bridge day. Although, I've heard people have happily used the SRTE Stop on 1000-foot drops before... 8)
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SELF BELAY

Postby CAVERSCOTTM » Mar 1, 2006 10:08 am

WHAT IS THE BEST TYPE OF SELF BELAY TO USE. I HAVE BEEN TRYING TO FIND ONE TO USE.
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Postby van » Mar 3, 2006 4:38 pm

Wow, I'm amazed someone pulled my 6-year-old FW post out of the archives (see Scott's post a couple pages ago). Who did that, Scott or the moderator?

As I said in that post - and while talking to Tiny at OTR - I learned about it from my Dayton Underground Grotto-mates who had been using it for years already (Hey, Colin, Kenny - how come you guys never post here) on their frequent TAG trips. So it's been in use for at least 10 years now.

A previous poster asked about hanging upside down or sideways. I don't think anyone seriously uses the FW as a disconnect safety; it's a "knocked out by a rock" safety. So when a FW engages, the rope is still going through your rack. You're only a *little bit* sideways, maybe a *little* uncomfortable, but no big deal. Besides, if a FW engages, you're probably unconscious anyway, so don't worry about it. Just worry that your companions are competent to get you off & down quickly.

I've demonstrated the FW at grotto meetings and vertical practices. I'm 185 lbs and it stops me cold, and it's ridiculously easy to start descending again. People seem impressed, but they don't actually use it. It's a hassle. I don't actually use it, except in very rare situations where I think I might get rocked in the head. Especially since I use a micro-rack, where the FW doesn't interfere with dropping bars or changing hands.

Even in that rock-in-the-head scenario, someone using a Stop obviously doesn't need it. Someone using a well-tuned 6-bar rack, as Scott pointed out, doesn't need it (IMO, the ideal situation is when you are pulling bars down to move - not that I achieve that consistently).

So the FW is a useful tool, but only in the right situation. Besides, as others have said: practice practice practice, figure out what works for you by trying it, not be reading this board.
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Postby hank moon » Mar 3, 2006 7:27 pm

van wrote:Even in that rock-in-the-head scenario, someone using a Stop obviously doesn't need it. Someone using a well-tuned 6-bar rack, as Scott pointed out, doesn't need it (IMO, the ideal situation is when you are pulling bars down to move - not that I achieve that consistently).


Not so fast (har har...). What happens when the rope is released depends on several factors, among them the weight of the user, the diameter, stiffness, and overall condition of the rope used (dirty, fuzzy, wet, dry, etc.), and how much rope is below the device. Bet others can add to the list. A well-tuned rack is desirable and can help mitigate the risk of losing control, but it's impossible to "tune" it for all the aforementioned variables.

Scott McCrea wrote:if a rack is tuned, set up and used properly, it is difficult to lose control, even if unconscious. BLANKSPACENote: emphasis added by Hank


Got data? :shock:

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Postby Rastus » Aug 27, 2006 4:57 pm

Just to clarify. . . .
The literature with the Petzl Shunt pictures it riding below the figure-8. Am I correct in understanding that this would be inappropriate for a rack as it would interfere with the necessary manipulation of the rope to change bars, etc.?

I'd appreciate some comments from those who have tried shunts. With it riding above the rack, did you dispense with manipulation of the bars?

Thanks.
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Postby Scott McCrea » Feb 28, 2007 6:20 pm

Here's another article about the French Wrap. It's on page 10.
http://cave.pure.net/~bats/downloads/ne ... ar2006.pdf
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Postby chh » Mar 1, 2007 10:27 am

I use a FW sometimes when climbing especially if I know there to be loose rock present. I teach it to new climbers as well. I use it below my device precisely because of the ability to still use only one hand while controlling the FW and the rate of decent.

I believe that you COULD use a rappel safety above your tube style or Stop style device safely, but the drawbacks aren't worth it to me. i.e. mandatory 2 hand operation. I don't buy the "it will extend out of your reach" argument for tube style devices. If you can adjust the FW so it doesn't get sucked into your device, than you can adjust it so it doesn't get out of your reach. With a rack on the other hand, I could see how an above-the-device safety could get away from you. I don't use a FW with a rack or a Stop: above or below. With a rack this is because I do frequently adjust the number of bars I am using on my 6 bar. I might feel differently if I used a micro rack and used the same number more frequently. Also, I don't remember who suggested introducing a screamer or ripper into the FW system, but even if I did understand that correctly I think it uselessly complicates the system. Same goes for the shunt actually. But I guess I trust cord more than metal if convenience isn't going to be increased at all. Just my own brain.

Cavegrrl, I'm interested to hear a little more about using the FW on a longer drop. Did it glaze at all? What diameter did you use? How about dropping or adding bars? Do you keep the FW on your leg or low and in the center of your harness? Longest I've ever used a FW on is 60 meters with a tuber. Never experienced any glazing or anything, but I also use skinny (6mm) cord and wonder about longer distances. I'm an advocate of the FW, but never use it with a rack. Just curious.
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Postby Princess Butterfly » Mar 29, 2007 4:58 pm

I have a lot of long drop experience with a FW, 9000' of it on tandem rappels over 400'. French wraps do need to be replaced every so often because of glazing, but that amounts to $2 of cord every couple years. You won't glaze it from one trip. I have two different FW's one for shorter drops over my hip and one for longer drops where it will between my legs.

I normally wear the french wrap on my hip for shorter drops. Its under my brake hand at all times while I am rappelling. On longer drops, ie Golindrinas, I put the FW between my legs because of the rope weight. This is the best way to do it if you have someone under you on a tandem rappel as well. The FW is nice to have on longer drops, especially when you have to manhandle 90lbs of ropeweight to drop a bar. Once you set the french wrap you are not going anywhere and can use both hands to pop a bar.

We teach the french wrap at vertical practice at the house, but TinY makes sure that every student knows how to handle a rack without one before using it. Its all taught in a tree or the climbing rig in our backyard before it is ever used in a pit.
See you on a long rope soon,

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Postby chh » Mar 30, 2007 8:10 am

Princess Butterfly wrote:On longer drops, ie Golindrinas, I put the FW between my legs because of the rope weight. This is the best way to do it if you have someone under you on a tandem rappel as well. The FW is nice to have on longer drops, especially when you have to manhandle 90lbs of ropeweight to drop a bar. Once you set the french wrap you are not going anywhere and can use both hands to pop a bar.


That makes a lot of sense. I never thought about the wrap making it easier to add/drop a bar with 80 pounds of rope under you. I usually just pop my QAS on there if I want to manhandle a lot of weight on the rope. I'll have to try this.
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Postby Mark620 » Mar 30, 2007 9:38 pm

we used a FW the other day to pull fence posts out of the ground :shock:
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