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Fast passing of the knot for rappelling or lowering

Original Post
jktinst · · Unknown Hometown · Joined Apr 2012 · Points: 55

Some time ago, while considering self-rescue scenarios involving passing a knot on a regular rappel or a tandem or counterbalanced rescue rappel, or when lowering a partner, I realized that it is quite straightforward to get an EDK knot to pass through a loose munter, even from a distance. The only obstacle to the full passing of the knot is the munter's loop wrapping over the knot just as it exits the hitch and staying hooked there so that letting more rope through just keeps extending the loop. With a loose munter, the EDK can be easily released from this loop with a bit of shaking.

With a tensioned munter, other solutions are required. If the person being lowered or the rappeller can briefly take his own weight partly off the rope (stepping on a foothold and/or pulling himself up by one hand on the first rope), the loop can be unhooked from the knot by hand. Of course, if the rope can be completely unweighted by stepping on a ledge, passing any knot with any device is a piece of cake. However, there are many circumstances when even partial unweighting is not possible.

I tried using a biner (or two) to lever the loop off the knot. I also tried using the two tails of the knot (poking them back through the loop on either side of the knot and pulling them together). These options are quite hard if the loop is kept short. They become easier with a longer loop but then, of course, you get a longer drop, which is not great at the best of times and may be quite bad in some situations.

The trick I finally hit on is to leave one of the EDK tails (the skinnier one if the two ropes/cords are of different diameter) long enough to make a second munter on the same biner. This second munter is used to do a very quick weight transfer that allows loosening and unhooking the loop of the primary munter. The unusually mild weather we had before Christmas gave me a chance to test this for both rappelling and lowering with different combinations of ropes and cords and I found it to work quite well. It's also very fast.

I can provide the detailed sequence (including safety back-up steps) but I am still wondering if this has already been described elsewhere. When I looked for any reference to this technique, I didn't find much. There are, of course, tons of variations on the standard (and more time-consuming or gear-intensive) weight transfer options for passing any knot with any braking device (with PMMO, ascenders, prusik + step-in sling, etc.). I had also seen before and found again a few of rgold's descriptions of the "munter pop-to-ATC" knot-passing method (eg on this 2009 supertopo thread). That is also a very fast method for passing the knot and I discuss the relative merits of this compared to the "EDK munter pass-through" in greater detail below. Tyson & Loomis describe the munter pop (munter-to-munter) for lowering in their self-rescue book. I was also reminded that a fig. 8 descender can let knots pass and can pass an EDK very easily but, of course, hardly anyone uses these anymore and no one would want to carry one just for this unless its use was planned in advance.

In the end, the only references I found to passing an EDK through a munter were Karl Baba's post on the second page of that same 2009 supertopo thread and bryn's post half-way down this ukclimbing thread. However, neither discussed the issue of unhooking the munter's loop from the knot under full body weight. Have I missed other key references to this technique (perhaps including other loop-unhooking tricks) or other fast methods for passing the knot on rappel or lowering?

As I've discussed in the past regarding the loose munter, the only time when passing an EDK does not work is if the knot is too fat to go through the biner. Under full body weight and with the munter in front of the person controlling it, a somewhat fatter knot may be passed than in the "loose munter/remote passing by shaking" situation. For example, I was able to fairly easily push an EDK between two 10.3mm through a Petzl William. Since the biner used should be the largest one available and since, by the time the second munter must be installed, the knot has already passed through the biner, making that second munter on the same biner is not a problem.

Comparing the munter pop and EDK munter pass-through methods: if the weight can be partly taken off the rope, the EDK passing is faster and easier than the munter pop. If not, the munter pop has a slight speed advantage. Of course, if you know (or strongly suspect) that the knot will be too big for the largest munter biner you have available, the EDK pass-through is obviously not an option. On the other hand, the munter pop option works best if you have only one knot to pass. Obviously, when passing from a munter on the first rope to an ATC on the second, no additional munter pop knot-passing is possible. However, even when passing munter-to-munter, things get complicated for additional knots. You need the munter on the "previous" rope to be tethered as long as possible (while remaining within easy reach) and that of the "next" rope tethered as short as possible (while avoiding interference with the 3rd hand back-up hitch). If you want to pass a second knot with the same method, you'll need to have the biner for the "next" munter tethered on a load-releasable short tether that, once released, will extend to just the right length for the following munter pop. Doable but not easy, and you need to know beforehand how many knots you will need to pass.

The EDK munter pass-through works much better for any knot beyond the first one, especially if the final number of knots is not known ahead of time. For example, if you find that the two ropes tied together will not allow you or your lowered partner to reach the ground or the safe ledge you're aiming for, you can simply tie an additional length of spare rope or cord at the end, pass the knot, keep going down and repeat as necessary (just be sure to be able to control the descent, and block it as needed, on whatever cordage you're using next).

FrankPS · · Atascadero, CA · Joined Nov 2009 · Points: 276

Man, that was long! I got through about three paragraphs. Maybe the next reader will do better.

Ryan Knowlton · · Boulder, CO · Joined Jul 2014 · Points: 20

If I was in a situation where i was rapping with a munter for self rescue it would be ideal to back it up with a prusik as well, but when doing so for a munter rappel where the brake hand is up the difference I would imagine is instead of a third hand your prusik is on the load side so if I was in a situation where I handt read on it and had to do it myself thinking through with what I have, I would go down to EDK, stop and load the prusik, feed the knot through with one hand on the brake strand ready to cinch it up if needed if the prusik starts to slip, which is shouldnt but you know just be ready in case.

Then you have the EDK between your prusik and your munter. Its hard to undo a weighted prusik so I would probably tie of the munter MMO style tie another sling klienheist or prusik style under the the edk and above munter, and step into it so as to weight that and unweight the prusik thats above the edk, loosen or untie it sit back on the MMO munter, use my new prusik below the edk, untie the mule hitch and continue with a back uped rappel.

All told this requires two bieners, one for the munter rap, one for your backup prusik, and two slings/cords, one for your prusik and one for the step up to untie the high one, through in a pinch you could do it with just one if you use the loose end of the rope below you and pull it up to tie a friction hitch or even just an alpine butterfly under the MMO though I feel like that would get a bit wonky.

please note, Ive not had to do this, but I like thinking through what I would do in shit situations and I think its a good skill to have I'm sure theres better ways and I'm open to hearing them.

Bill Lawry · · Albuquerque, NM · Joined Apr 2006 · Points: 1,812

My gut feel is that dealing with the coils introduced by rapping / lowering someone on a munter is not worth any ease of being able to pass an EDK through the munter - just my opinion.

Edit to add: That's not to say using a munter is bad. It is always an option when your usual belay / rap device is not available for some reason. I just would not choose it for the possible benefit of passing a knot through it.

jktinst · · Unknown Hometown · Joined Apr 2012 · Points: 55
Ryan Knowlton wrote:If I was in a situation where i was rapping with a munter for self rescue it would be ideal to back it up with a prusik as well, but when doing so for a munter rappel where the brake hand is up the difference I would imagine is instead of a third hand your prusik is on the load side ...
Interesting alternative. The point of this thread is, of course, to add useful and fast knot-passing tools to the self-rescue toolbox. Looking only at the knot-passing on rappel, your method has a certain appeal and would probably go about as fast as mine. Your step-up prusik would become the new load-side back-up for the next part of the rappel so it appears to be quite economical in prusik-installations and take-downs, which are time-consuming steps in the more standard knot-passing procedures.

However, you may want to test your premise that in a rappel on a munter, you would keep the brake strand side-by-side with the load strand. That is indeed how you get the most friction out of a regular munter, which is essential for lead belaying, but for rappelling, keeping the two strands together is not practical. Braking downward reduces friction but there's plenty enough left to hold body weight and it allows easily stopping and restarting the rappel using an ATC-style 3rd-hand. Depending on the situation, you may need to do this more than once before getting to the knot.

With your system, you would need to have a way to do this that avoids loading the back-up prusik. I don't really see any other option than the mule-overhand (or similar) block if the brake strand it to be kept in the upward hold. However, having to install and undo this block at each stop would be quite time-consuming. The other disadvantage is that, in certain self-rescue rappel situations, stepping up on anything, be it a foot hold, a prusik sling, a rope loop, etc. may be quite out of the question.

Finally: keeping load and brake strands together is a useful position for belaying a partner on a direct munter belay, whether he's climbing or getting lowered, and, in this position, a brake-strand 3rd hand works really well. In this case, sticking with your plan of having a load-side prusik take the weight to be able to pass the knot easily (in this case, transferring the weight to the anchor) would involve installing and undoing a separate PMMO, which would be counterproductive.
Bill Lawry · · Albuquerque, NM · Joined Apr 2006 · Points: 1,812
jktinst wrote:Interesting alternative. The point of this thread is, of course, to add useful and fast knot-passing tools to the self-rescue toolbox.
One possibly useful trick when just one knot is involved:

In this method, first person does not need to pass the knot on rappel. And, in ideal circumstances, no one but the last person need pass the knot on rappel.

While at the rap station:
a) person A - about to go down - rigs their rap device just below the knot and ties it off;
b) other person B rigs their device just above the knot;

Then:
c) person B lowers person A until out of rope;
d) person A then releases his / her rap device and continues on rappel.

Probably good for person B to have a plan for keeping the lower excess rope under control.
Gunkiemike · · Unknown Hometown · Joined Jul 2009 · Points: 3,492

I didn't real the long OP. But I understand that knot passing is pretty routine, as evidence by the various British and AMGA test scenarios. No need to re-invent anything.

bearbreeder · · Unknown Hometown · Joined Mar 2009 · Points: 3,065

passing the knot is pretty simple if you practice it enuff ...

there are tips and tricks to make it easier ... but even the "standard' way is fine

be VERY careful about super long tails on rap ... theres been a case or two where someone setup a rap on a "tail line" and rapped right off

jktinst · · Unknown Hometown · Joined Apr 2012 · Points: 55
bearbreeder wrote:passing the knot is pretty simple if you practice it enuff ... there are tips and tricks to make it easier ...
You're usually more generous with relevant information. Would you please provide descriptions or links for these tips and tricks for everyone's benefit?

bearbreeder wrote:... be VERY careful about super long tails on rap ... theres been a case or two where someone setup a rap on a "tail line" and rapped right off
This would be much more of a risk with the "munter pop-to-munter" knot pass and with most of the standard knot-passing techniques than with the "EDK munter pass-through". With the "pop" and other methods, you need to install the rope brake (munter, ATC, etc.) on the second rope and transfer to it. Therefore there is a possibility that you might install it on a long tail instead of the second rope.

With the EDK pass-through, you stay on the same primary munter throughout the whole rappel or lowering, past knots and onto successive ropes. Not only do you never undo this munter or come off its biner until you're completely finished, but you don't even undo the second munter either so there is no risk of undoing the wrong munter by mistake. You install the second munter and when you're done with it and are resuming the descent after passing the knot, controlling that descent with the primary munter, you just let go of the second one and let the knot simply pull it out of the biner.

There's no chance either that you'll get to that point at the end of the procedure confused about which munter to let go of. The primary munter will be the one with the 3rd-hand autoblocking hitch. Where an error might have crept in is if you installed that second 3rd-hand on the long tail instead of the second rope to begin with. It would work as a braking strand at first and let you control your descent for a few more inches before the knot started passing through the primary munter and biner. However, your mistake would be obvious as soon as it did start passing. With each of the two passages of the knot through the biner, the tails are left trailing behind on the other side of the biner and you have to pull them out to proceed (another reason why you wouldn't want them super-long to begin with). With this mistake, you would see right at the first biner passage of the knot that you could only pull out one of the tails and couldn't proceed further. As this point, the hitch would still be functioning as a 3rd-hand, effectively blocking the munter while remaining easily releasable, so correcting the mistake would be quite straightforward.
Yer Gonna Die · · Cragville · Joined Oct 2012 · Points: 175

With a munter lower you can force the knot through if the knot is small enough and the carabiner is big enough.

bearbreeder · · Unknown Hometown · Joined Mar 2009 · Points: 3,065

perhaps you can provide photos or diagrams of your system?

that would make it clearer

the thing about the "standard" knot pass is that its more or less applicable to any knot passing situation ...

there are times when you dont choose the "tails" but they choose you .... ie rapping down and you discover a core shot ... you need to isolate that loop right there, no tails

;)

Marc801 C · · Sandy, Utah · Joined Feb 2014 · Points: 65
Gunkiemike wrote:I didn't real the long OP. But I understand that knot passing is pretty routine, as evidence by the various British and AMGA test scenarios. No need to re-invent anything.
My general rule of thumb is that if a technique takes multiple paragraphs in multiple posts to explain and discuss, then it is not suitably simple enough to actually use in a real climbing situation.
Mathias · · Loveland, CO · Joined Jun 2014 · Points: 306

This may simply not be helpful but I'll share anyway.

A while back my partner and I were rapping a route but we got a knot in one strand and the safety knot on the end of that same strand stuck in a crack below the knot in the middle. So we couldn't pull the rope up to get the knot in the middle out.

I had a spare tube device with me (which I always carry on my trad harness). The plan that formed was to rap on extension to above the knot, use the spare device directly to my belay loop, below the knot, and transfer my weight to it. Then leave my original device above the knot so he could remove that and do the same.

We didn't end up needing to do it as the tail came free when I got to the knot we thought we'd have to pass, so I was able to undo it. But I think it would have worked just fine.

jktinst · · Unknown Hometown · Joined Apr 2012 · Points: 55
bearbreeder wrote:... the thing about the "standard" knot pass is that its more or less applicable to any knot passing situation ... there are times when you dont choose the "tails" but they choose you .... ie rapping down and you discover a core shot ... you need to isolate that loop right there, no tails ;)
Yes, the standard knot-passing methods are an essential tool in all self-rescue toolboxes because they can work in most or all situations, with any knot, any brake, etc. I have outlined the conditions that would prevent the EDK pass-through from working but these conditions are easy to ensure from the beginning. Within those parameters, the EDK pass-through is fine for a simple rappel or a counterbalanced or tandem rappel with an injured partner, and for lowering a partner.

Regarding the core shot situation, that normally calls for the rope to be cut sooner or later. With the standard knot-pass, there is no strong reason why it would need to be cut right there and then but if you have a good reason to use the EDK pass-through (more than one knot to pass, in a hurry, etc.), there is no reason NOT to cut it and make the two tails you need right away. However, if there are other situations when the EDK pass-through really will not work, I definitely would like to know about them.

Rich zz wrote:With a munter lower you can force the knot through if the knot is small enough and the carabiner is big enough.
This is funny. Were you trying to boil the OP down to a single sentence? Yes, that is the essence of the technique, except that, as I explained, under full body weight, you can't just pass the EDK through the munter. It catches on the munter's loop just after it's made its second pass through the biner and wrestling the loop off the knot can be quite hard. The intermittent weight transfer to the second munter that I describe makes this much easier.

Marc801 wrote: My general rule of thumb is that if a technique takes multiple paragraphs in multiple posts to explain and discuss, then it is not suitably simple enough to actually use in a real climbing situation.
I guess that you've never read a self-rescue manual because there's always way too much text explanation and too many diagrams and photos. Most, if not all self-rescue techniques take way (waaaayyyy) longer to describe and represent step-by-step for someone who's never seen it than they take to carry out once you know how to do them. But the point is that this is a discussion about a potentially new or previously known technique that may have flaws I have missed, not a self-rescue manual description of a well-established method.

To practice this, or any other knot-passing method, it would obviously be best to have a set-up where you can easily step up about 3 m and rappel back down repeatedly (easy short route, tree & ladder, etc.). With this set-up, one shouldn't need more than 3-4 practice rappels to get to a point where the EDK pass-through takes them 25-30 sec. tops.

For those who may be interested in and able to stomach text explanations, here is the detailed step-by-step procedure for a rappel. This can be easily transposed for lowering instead.

- stop and block the main munter with the first 3rd-hand just before the knot (+ leg wraps or fig. 8 bight clipped to harness for an additional back-up if preferred)
- install the second 3rd-hand on the second rope and block it
- remove the first 3rd-hand
- release the second 3rd-hand and allow the main munter to slide, letting (and helping, if necessary) the knot pass twice through the biner (pulling the tails to follow the knot on the first pass)
- block the main munter again just as the knot exits the biner for the second time and as it starts catching the munter's loop
- thread a second munter beside the main one with the long tail and block this second munter by hand
- release the main munter until the weight is on the second one and the loop of the main munter is loose, then block the 3rd-hand again
- pull the loop off the EDK and pull the short tail out of the main munter
- cinch the main munter down on the biner and move up and block the 3rd-hand
- let go of the second munter and tie the anti-inversion knot on the short tail
- resume rappelling on the main munter, letting the second munter slide out of the main one, pulled by the EDK.

Initially, I wasn't planning on doing diagrams or photos because I think that it's much simpler to just explain that you need to install two munters side-by-side on a large biner (one of which has a knot passing through it with tails sticking out) than to provide a "plate of spaghetti" illustration. Then I figured that I might be able to do it with schematic diagrams. I spent a good part of yesterday afternoon on them but then couldn't get my printer-scanner working so illustrations will have to wait a bit, sorry.
jktinst · · Unknown Hometown · Joined Apr 2012 · Points: 55

printer-scanner is fixed.

Here are the illustrations of the steps in the EDK pass-through.

Best I could do.

Image size remains an issue. Click on it to view the larger image and get zooming options.

EDK pass-through

bearbreeder · · Unknown Hometown · Joined Mar 2009 · Points: 3,065

thanks for drawing it out ... maybe im STOOPID but i really dont see how it works under full body weight

regardless the "standard" knot pass looks to be alot simpler ... not to mention it works with any device, biners and on dual strands ...

and theres no need to step up if you use a releasable hitch with the friction knot

;)

Insert name · · Harts Location · Joined Dec 2011 · Points: 46

I pass knot all of the time (for work).

Why would you not just use a friction hitch? There are 100 other simple ways.

Also if there is a section of bad rope just do a double alpine (butter fly the bad section leave extra and put another good section.

There is a reason why people use the same techniques and it normally means that they are the best cross between safety/efficiency.

jktinst · · Unknown Hometown · Joined Apr 2012 · Points: 55
bearbreeder wrote:... i really dont see how it works under full body weight ...
I did at least 10 knot-passes on single-strand rappels with this technique when I tested it over Christmas, hanging from a tree branch, using the following rope/cord combinations:
- 8.5 X 8.5 mm doubles
- 10.3 X 10.3 mm (two ends of the same single rope)
- 10.3 X 8 mm dynamics
- 10.3 dynamic X 7mm static

For the lowering, I did only 2 tests with the 8.5 X 8.5 mm combination (had trouble tearing a guinea-pig away from her cousins, or maybe it was from her cell/laptop/games console), lowering from a redirect anchor on the same tree branch, with the belay anchor at the base of an adjacent tree. The technique worked just fine under full body weight in all cases.

bearbreeder wrote:...regardless the "standard" knot pass looks to be alot simpler ... not to mention it works with any device, biners and on dual strands ... and theres no need to step up if you use a releasable hitch with the friction knot ;)
PosiDave wrote:...Why would you not just use a friction hitch? There are 100 other simple ways...
Timewise, for me, the issue with the standard methods is setting up and removing a prusik solely for the weight transfer. While I like the hedden for a 3rd-hand, the only hitch I trust for full body weight and higher loads is the prusik, which takes longer to install, dress and remove than most other friction hitches. Installation of a 4-wrap prusik with a long cord sling takes me about 20 sec. Removing it after a full weighting and stowing it: about the same again, and then there's installing and letting out the MMO on the prusik sling as well. So for me, the EDK pass-through is somewhere between two and three times as fast as the standard method. But maybe that's just me.

That's why I like the speed advantage of techniques that do not involve installing a PMMO for the weight transfer, like Rich's munter pop-to-ATC (or those described by Bill Lawry and Mathias, although they clearly have relatively limited applications). Saving 30-40 sec. on a knot-pass may not seem like much but when bringing back down an unconscious leader or bailing in a thunderstorm, every second counts.
Insert name · · Harts Location · Joined Dec 2011 · Points: 46

A Klemheist or a Bachman work pretty damn well.

A tibloc is also a great invest for that reason.

If you create a belly in the rope and leave the friction hitch attached, it is pretty easy.

I have lowered a 200lb man with me on a munter and doing that on a long rap seems like it would leave far more room for error and passing a knot normally causes a bit of a jolt (not really what you want in the rescue field when there's a possible neck/spine injury.

There are 1000 ways to skin a cat. Just throwing in my two cents as I also like to question "regular" techniques

Insert name · · Harts Location · Joined Dec 2011 · Points: 46

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clipping into the Belly with a Biner allows you to do it with one ATC and no munter

You can use a
Combo of atc/munter or atc/atc and that allows you to lower to the knot and pop right over.

jktinst · · Unknown Hometown · Joined Apr 2012 · Points: 55

Klemheist or Hedden: same thing. In my experience, under full body weight, both stand a fairly good chance of binding themselves fast and be extremely difficult to loosen. A prusik may be a bit difficult to loosen but will never bind itself fast. And a Bachmann on a single strand of rope (say an 8.5 mm double)? Seriously?

You also almost lost me there with leaving the friction hitch behind. My initial motivation for exploring fast knot-passing is counterbalanced rappels. Leaving stuff on the rope in a CB rappel is just asking for a lot of trouble.

Finally: let's leave the other 999 aside for now and try to understand just this one. I take your word that you've tandem-rappelled with a 200 lbs man past a knot with this system but I 'm afraid that you're going to need to be a lot more explicit with your text explanations or your drawing (or, better yet, both) for your technique to make any sense to me at all. Where is the rappeller in all this? Is the "overhand" shorthand for something else, like a mule-overhand or some such? How does it attach to the rope? Is there a biner in there?

I have tried a couple of set-ups that sort of look like your drawing but have not been able to find a way that makes use of the bight below the knot to transfer my weight from one rope to the next (or from one rope, to the bight and then to the next rope, as you seem to suggest). I just keep coming back to the "long-tethered-to-short-tethered brakes" knot-passing techniques used in rgold's munter pop-to-ATC and in Mathias' example.

Despite the fact that I can't make head or tail of this, it still looks like you're installing a friction hitch specifically for the knot-passing, which, as I said, for me is the time-consuming part of the procedure.

Guideline #1: Don't be a jerk.

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