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dave schultz

[TR] Liberty Ridge w/ Partial Ski Descent 4/11-14

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I'm late to this thread, but this needs to be said for any less experienced climbers looking in this thread:

 

DO NOT SET UP YOUR RAP USING A TAG LINE IN THIS WAY; YOU COULD END UP DEAD

 

Always make sure that you set up the rap in such a way that you could load only the larger (dynamic) rope safely; that is, ensure that even if your tag line was not getting enough friction and so was slipping through your belay device, that you have a biner or some other device will prevent the entire setup from slipping through the anchor. In this example, the rap ring and knot are on the WRONG side of the v-thread.

 

vthread

 

IMG_20140413_171836.jpg

 

Tag line worked great for raps

 

In this pic with the v thread, is the tag line running through the v thread holes? Have not seen that setup before, although also haven't climbed with a tag line either, so wondering if that is a typical setup. Obviously leaves nothing behind when you pull the ropes, but I'd be concerned (not having tried it before) with friction when trying to pull them.

Edited by Quint191

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DO NOT SET UP YOUR RAP USING A TAG LINE IN THIS WAY; YOU COULD END UP DEAD

 

Always make sure that you set up the rap in such a way that you could load only the larger (dynamic) rope safely; that is, ensure that even if your tag line was not getting enough friction and so was slipping through your belay device, that you have a biner or some other device will prevent the entire setup from slipping through the anchor. In this example, the rap ring and knot are on the WRONG side of the v-thread.

 

Quint, I think you misunderstand what is happening in the picture. The tag line and the dynamic rope are tied together with a simple overhand knot (standard way I think 97% of us do it). Then the tag line is fed through the v-thread and pulled through; you could fed the tag line through, then tie the ropes together. The reason the dynamic rope was NOT fed through the v-thread was to prevent damage to the tip of the dynamic rope by the v-thread tool; the system would work the same if the knot was on the other side (ie the dynamic rope was fed through the v-thread). Regardless, in our set up, and in the picture, the 6mm rope is going through the v-thread. Then both the tag and the dynamic are fed through your rappel device, so you are weighting both and using the friction from both. The only issue I know of with this set up, that is not a factor when using two ropes of similar diameter, is that you can experience knot slip. With a 8mm vs a 6mm, there is no knot slip (but was watched very closely to ensure there was none, in other situations, there could be, but we did not experience it). If there was knot slip, you would have had to do the traditional tag line set up (not going to describe it here, I'm sure we all know what it is, or you can Google it). Perhaps the term "tag line" is not the most accurate way to describe the smaller, 6mm cord. It was essentially using two normal ropes, just one of the normal ropes was 2mm smaller and 5m longer, and more static than dynamic.

 

I hope that clarifies the system up for you. If you still have safety issues, please voice them.

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DO NOT SET UP YOUR RAP USING A TAG LINE IN THIS WAY; YOU COULD END UP DEAD

 

Always make sure that you set up the rap in such a way that you could load only the larger (dynamic) rope safely; that is, ensure that even if your tag line was not getting enough friction and so was slipping through your belay device, that you have a biner or some other device will prevent the entire setup from slipping through the anchor. In this example, the rap ring and knot are on the WRONG side of the v-thread.

 

Quint, I think you misunderstand what is happening in the picture. The tag line and the dynamic rope are tied together with a simple overhand knot (standard way I think 97% of us do it). Then the tag line is fed through the v-thread and pulled through; you could fed the tag line through, then tie the ropes together. The reason the dynamic rope was NOT fed through the v-thread was to prevent damage to the tip of the dynamic rope by the v-thread tool; the system would work the same if the knot was on the other side (ie the dynamic rope was fed through the v-thread). Regardless, in our set up, and in the picture, the 6mm rope is going through the v-thread. Then both the tag and the dynamic are fed through your rappel device, so you are weighting both and using the friction from both. The only issue I know of with this set up, that is not a factor when using two ropes of similar diameter, is that you can experience knot slip. With a 8mm vs a 6mm, there is no knot slip (but was watched very closely to ensure there was none, in other situations, there could be, but we did not experience it). If there was knot slip, you would have had to do the traditional tag line set up (not going to describe it here, I'm sure we all know what it is, or you can Google it). Perhaps the term "tag line" is not the most accurate way to describe the smaller, 6mm cord. It was essentially using two normal ropes, just one of the normal ropes was 2mm smaller and 5m longer, and more static than dynamic.

 

I hope that clarifies the system up for you. If you still have safety issues, please voice them.

 

I think the concern he was raising was that with your setup, if you lose control of the tag line (i.e., not enough friction) you can lock down the dynamic line completely and it won't stop you because the knot is on the opposite side of the v-thread from the tag and therefore will not jam up against the ice and allow you to stop. Having not rapped on a setup like this before, I don't know how much of a concern this is. Do you tie the ends together in your setup? If so, that would stop you (eventually).

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Although the discussion of the v-thread has been beaten to a bloody pulp, I'll kick it one more time for good measure:

 

If you've never used a "tag line", bear in mind that accessory cord (6-7mm) is much LESS durable than climbing rope. Inspection and replacement of thin cordage should probably be done often (every trip, or every rappel if your cord snags). I'm assuming this is why Dave says that his tag line is "much longer" than the 30m, 8mm line he used: so he could cut the tag line and still have a 30m rap?

 

 

 

 

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DO NOT SET UP YOUR RAP USING A TAG LINE IN THIS WAY; YOU COULD END UP DEAD

 

Always make sure that you set up the rap in such a way that you could load only the larger (dynamic) rope safely; that is, ensure that even if your tag line was not getting enough friction and so was slipping through your belay device, that you have a biner or some other device will prevent the entire setup from slipping through the anchor. In this example, the rap ring and knot are on the WRONG side of the v-thread.

 

Quint, I think you misunderstand what is happening in the picture. The tag line and the dynamic rope are tied together with a simple overhand knot (standard way I think 97% of us do it). Then the tag line is fed through the v-thread and pulled through; you could fed the tag line through, then tie the ropes together. The reason the dynamic rope was NOT fed through the v-thread was to prevent damage to the tip of the dynamic rope by the v-thread tool; the system would work the same if the knot was on the other side (ie the dynamic rope was fed through the v-thread). Regardless, in our set up, and in the picture, the 6mm rope is going through the v-thread. Then both the tag and the dynamic are fed through your rappel device, so you are weighting both and using the friction from both. The only issue I know of with this set up, that is not a factor when using two ropes of similar diameter, is that you can experience knot slip. With a 8mm vs a 6mm, there is no knot slip (but was watched very closely to ensure there was none, in other situations, there could be, but we did not experience it). If there was knot slip, you would have had to do the traditional tag line set up (not going to describe it here, I'm sure we all know what it is, or you can Google it). Perhaps the term "tag line" is not the most accurate way to describe the smaller, 6mm cord. It was essentially using two normal ropes, just one of the normal ropes was 2mm smaller and 5m longer, and more static than dynamic.

 

I hope that clarifies the system up for you. If you still have safety issues, please voice them.

 

 

knot slip isn't the only problem.

 

fwiw, I have experienced the case where the smaller diameter rope moves faster through the device while rapelling. with similar ropes but different diameters (ie, similar being same sort of stiffness/bendability), the larger diameter rope will experience more friction in the device than the smaller diameter rope. it's a function of the resistance of the rope to bend at a given radius - the easier it is to bend (ie, smaller diameter) the less friction there will be through the device.

the risk is that the smaller diameter rope will slip right through the device, and you be left attached to only one rope and falling... but only if the knot is on the wrong side of the anchor.

granted, I'm probably putting too fine a point on it, but if I were to analyze your situation from the comfort of my computer.... since you were using a static rope, which may have been a bit stiffer than a dynamic rope of equal diameter, you probably had similarly matched friction through the device.

ultimately, you were there, you set up the ropes, you rapped, and everything was fine. because of my experience, and I think other people have had similar experiences, I generally set up the rap anchor so that the knot is on the tag-line side of the anchor (have to pull the tag line to retrieve ropes), so that if there is less friction from the tag line, the knot keeps the rope from sliding through the anchor (be it rings, biner, vthread, or whatever).

 

sorry if this is totally clear already, or if I am muddying the waters more, but it did not sound like it was clear from the above messages.

 

---

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Since the majority of climbing accidents occur on rappel, it seems like any discussion regarding why or why not to use certain techniques is worth it.

 

6mm accessory cord is not rope. It's not even really a "tag line". Accessory cord does stretch, but has neither the strength or durability of dynamic rope or static line. Sure, it's breaking strength is somewhere around 8kN, depending on manufacturer, but that makes the margin for error very small.

 

I think it's important to be totally up front about what equipment we use and why: rapping anything using 6mm is a VERY advanced move, requiring some honest discussion about the limitations of the equipment. The last thing we want to see is a bunch of people out there on rock routes thinking there's no concern about rappelling on their 9.2 with a length of 6-7mm accessory cord.

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If you are just using it to rappel (either through an ATC or as a pull cord) then not stretching is a good thing.

 

These ropes/cords are very strong, certainly more than strong enough to handle any forces from making a rappel. Some of them (like the Esprit 6mm and the Edelrid 7mm) are also much stiffer than a climbing rope, meaning fewer tangles.

 

Sure there is the downside that you'd can't lead on it, and it is potentially less durable or edge resistant, but those are really the only drawbacks.

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Sure, it's breaking strength is somewhere around 8kN, depending on manufacturer, but that makes the margin for error very small.

 

8kn is a pretty healthy margin of error in this circumstance

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Except the 8kN isn't the breaking strength, particularly for a static rap line.

 

Knot factor reduces rope strength by 50%. Esprit 6mm breaking strength is rated at 2300 lbs. Knotting it reduces that to 1150 lbs.

 

Degradation - crampons, UV, previous shock loading, grit, abrasion, and bending, can further reduce breaking strength by as much as 50%, and this damage isn't always all that visible or detectable.

 

Breaking strength is now down to 575 lbs.

 

But hey, I don't weigh that much, right? One such a tiny static line, even a minor shock can double your effective weight - I can weigh 230 fully loaded, particularly with ski gear, some of me pals add 40+ lbs to that.

 

575/270 is less than 2x. Even a very shot static fall in the form of a minor loss of balance or the rope slipping off an edge can shock load such a line enough to snap it.

 

Feelin' lucky?

 

 

If you climb a lot, such practices can eventually bite you in the end when all of these factors line up. After all, that's exactly how accidents happen - several unlikely conditions line up.

 

It's one thing to hang your body weight on small stuff - you've got a rope and pro to back you up.

 

You've got no back up on rappel.

 

Feelin' lucky?

 

7mm is the smallest line I would ever rap on. That adds 21% to your margin of safety - Yes, I'll rap on a 6mm V thread - they get used once, so degradation isn't a factor.

 

To quote Tyrion Lannaster

 

"I like living"

 

 

 

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If you climb a lot, such practices can eventually bite you in the end when all of these factors line up. After all, that's exactly how accidents happen - several unlikely conditions line up.

 

This whole thread is about doing things the right way or the stupid way. For a whole lot of reasons, the knot goes on the side of the anchor with the thinner rope, always.

 

Does it matter every time? No. Is there any reason to be on the losing (falling) side when it does? Also no.

 

Climb smart. Don't fall. You could die. And don't cut gate locks. You probably won't die from that, but you make all of us look bad.

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It's the little, common habits that will keep you alive or kill you. I continually ask myself - what are the best practices for any given situation? Make exceptions when necessary, but at least know the risk you're incurring. In fact, several sites recommend NOT doing that.

 

Here's a link on how to use 6mm pull cords more safely than was done on this climb from the canyoneering crowd - who first started using lighter rap lines. You'll not not one setup puts the 6mm pull cord through the anchor.

 

Rapping with a 6mm pull cord

 

Be safe. Stay alive. Have fun.

Edited by tvashtarkatena

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Interesting about the road closure and the gate. I never knew snow machines were allowed. I would venture to guess that the road was closed because the NPS does not have anyone to manage that side of the park in winter.

 

While I have never cut a lock I have done other mischievous deeds while in various parks. At MORA one winter we parked at the Carbon Gate and dutifully hiked in. However, given it was a Saturday we expected the Ranger Station to be open. Nope. No self issuing permits either, nothing so we hiked in an played for a few days on the north side. When we came out, we met a few hats. Back then Gaitor running the show but was off and out of the state. They called him anyways, he knows me and knew that I might be in the area but passed the buck to another mutual NPS friend who was at another park. Soon most of my NPS friends wondered about our trip.

 

In the end NPS asked why we did not stop at the station in Wilkeson. What station? We looked an never found one besides for why wasn't the station at Carbon River open? Their response was cause it is the winter. Our response was given it was a weekend would it not seem logical to be where people would have to park? In the end no citation was issued.

 

 

The reason the dynamic rope was NOT fed through the v-thread was to prevent damage to the tip of the dynamic rope by the v-thread tool

 

Hahahaha. At this point I am not sure which was sillier cutting the lock or worrying about damaging the rope. As others have said you really want the knot to be on the skinny rope side. Yer going to spend more time dealing with the man then you would fixing (cutting off) less than an inch of yer rope.

 

 

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Just to jump in the tag line discussion since I'm a fan of 'em.

 

Used it tons with ice and also on some rock. Rapped all of Infinite Bliss with one.

 

5mm X 72M static

 

You just have to learn to work with it - can't toss it like you would a regular thicker rope

 

There is for sure faster travel of the skinny rope through the belay device and you will see the knot travel if you lack friction at your anchor and run the tag line through the anchor. I tried this at home when I first got it and it was very obvious. This is why it is a very good choice to put the thicker rope through the anchor and then tie your knot.

 

For even a freak event where a knot is sucked in, as a safety measure this is what I have done:

P10209502.JPG

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Doug - are you rapping on both your main climbing rope and the tag line? What is the diameter of your main rope in the photo?

 

With one exception, your photo shows exactly how I would normally do a tag line (the exception is that I tie to loop/biner backup into the main climbing rope). I generally only use a tag line like this with ropes 9.2 or larger, with smaller I would probably be carrying two ropes and thus no tag line is required.

 

The situation on Liberty Ridge involves a very small diameter main rope (8mm) and a similar diameter tag line (6mm). IMO there is no need to arrange a set up like pictured, as you are rappelling on BOTH the 6mm and 8mm. There is enough friction in the device, the one (or two) biners, and the prussik backup that the smaller rope will not travel uncontrollably through the device and there will be little if any movement of the knot as your rappel down (this was verified during all rappels).

 

After hearing all of the comments about the system, I think it would be SAFER to place the larger rope through the v-thread with the knot on the opposite side, and will probably do this in the future (though I don't think it's unsafe to have it on the side as we did).

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Rapping with both through the ATC. Rope in that photo is a 70M X 8.2mm Petzl Dragonfly. I've used the same tag with a 9.*mm single on rock.

 

The trip from the photo we climbed with the 8.2mm half as a single.

 

When I've rapped with the tag line I don't really expect to get much friction/safety from the tag, but it is nice to keep the rope in your hands - it is skinny and you can lose it easily to the wind. The extra friction doesn't hurt.

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