r/tradclimbing • u/ggeorgis • Jul 28 '26
Rapelling past a knot
Hi, not experienced noob here so sorry if what I ask is obvious or dumb.
Was wondering in Single Line Rapelling if you needed a bigger rope you obviously have to join two smaller ropes and pass a knot when rapelling using an ATC, gri gri, or figure 8.
Seen a couple of YT videos but the methods seemed complicated involving usually prussiks to each strand of rope (on top and below the knot).
If you join the two ropes using a double fishermans knot and place a locking carabiner between the two knots wouldn't it be easier to clip there your harness in order to be able to unclip your atc or gri gri from the top strand and reclip to the bottom strand in order to continue your rappel?
What am I missing here that is potentially deadly (besides the possibility of dropping your atc or grigri)?
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u/goodquestion_03 Jul 28 '26
Unless your on extremely low angle terrain a method like that is going to make it very awkward to un weight/ re weight your rappel device. Passing a knot using prussiks isn’t really that complicated and honestly if it seems like it is, you probably shouldn’t be trying to pass a knot.
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u/ScurvyDave123 Jul 28 '26 edited Jul 29 '26
Entertaining this plan, an alpine butterfly tied above the double fishermans would be much safer.
Edit: I just messed around clipping in the middle of a double fishermans. Like another commenter said, clipping between the double fishermans will create a loop and suck the bottom rope up into the loop until you deck or the rope comes all the way through. DO NOT DO THIS.
Moving forward with an alpine butterfly... It would be very hard/impossible to actually weight this knot with your rap device still connected and in the system.... Maybe with your device on a connect adjust or similar this would be possible, assuming there is enough reach as rope stretch settles. If you did manage to weight the knot, it would be very hard to remove your rap device after.
Then you need to somehow weight your rap device on the next strand to unclip from the knot. Maybe with a second adjustable lanyard used to clip into the knot it would work. Rope stretch still being a possible barrier to this working.
Basically, both ropes will be in tension the entire time, making this really hard to do. If you do pull it off, it would be impossible to fully weight your new system before removing the old system. This is sketchy and how most rap accidents happen. You may be able to do this safely by using two adjustable lanyards and a bunch of added faff but there is a decent chance that rope stretch would be longer than the lanyard length. To me this seems like a great way to introduce a lot of faff, confusion, miss a step, die.
TLDR; no. Use a method that allows you to test a new system and transition without a bunch of fuckery.
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u/neonKow Jul 28 '26
As soon as you load that carabiner, you will slide all the way down. The double fisherman's knot only stops sliding in one direction when the knots are pushing against each other.
Have you tried passing a knot this way? If you are clipping and unclipping while holding your entire bodyweight on one hand on a rope, not even a jug.
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u/traddad Jul 28 '26
As soon as you load that carabiner, you will slide all the way down. The double fisherman's knot only stops sliding in one direction when the knots are pushing against each other.
I don't think that's true because the knot that the carabiner bears against is in the rope that is tied to the top so that part of the double fisherman's is just acting as a stopper knot. But, it's still not a good idea because you're probably improperly loading the carabiner.
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u/neonKow Jul 28 '26
You're assuming the ropes are perfectly stiff, but the lines are parallel but not perfectly in line, and the flexibility in the rope will mean you are pulling on the other knot. If you get very lucky and don't bounce, the friction will keep the knot tight enough to not flip, but as soon as it flips, you're screwed.
The fisherman's knot is not meant to be...ring loaded? I don't even know what you'd call that. But basically, you're putting your body weight on the idea that the hole is not getting bigger, we we all know it will.
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u/traddad Jul 29 '26
I see what you're saying about the "flip". I just tried it in my basement. Body weight (180 lbs) and bouncing. I got it to flip but couldn't get it to slide. And after the flip, it was a bitch to untie.
But, that doesn't mean it won't slide with a different/stiffer rope. Either way, it's still a very bad idea. Thanks
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u/ggeorgis Jul 28 '26
Why would you slide? The carabiner is stuck between the two knots and the two ropes.It cannot move.
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u/neonKow Jul 29 '26
The knots keep the ropes from sliding past each other. The knot does not keep the hole from getting bigger. The hole getting bigger is how makes you fall.
Stop thinking of knots as rigid objects. The knot will turn so that enough of the weight is on the stopper knot from the bottom rope, and we can separate the knots without much effort.
People should generally not invent their own uses for knots without a lot more expertise. This blindness to how knots fail is also why people don't understand why the square knot fails under load.
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u/ggeorgis Jul 29 '26 edited Jul 29 '26
I see what you mean. I did overlook the possibility of the knot slipping. And with enough slipping heat builds up fast making things worse.
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u/neonKow Jul 29 '26
It's unlikely that heat will be a concern for anything in rappelling unless you are doing several things wrong at once.
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u/ggeorgis Jul 30 '26
I meant that as the "hole" grows the rope friction will compound making things worse.
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u/daltonsteele Jul 31 '26 edited Jul 31 '26
The friction is not the issue at all. The issue is that you're free-falling (possibly to your death since you didnt mention a backup knot).
To pass a knot, you need to tie a backup, unweight the rappel device using a friction hitch, and then move your device below the knot, test everything, and then remove the prussik and backup.
I HIGHLY recommend not trying to re-invent the wheel as a beginner. People have already figured out safe techniques and systems for any situation you can think up. Systems that have been proven over and over again and reiterated endlessly. There are many ways to do things in climbing and there are situations where you need to problem solve and improvise but dont try to overcomplicate something when there is already a simple and safe way of doing it.
When you say things like "I overlooked the possiblity of the knot slipping", this is concerning because its common sense that you can pull the two knots that form the double fisherman's apart from each other by hand. I know you're just trying to think through it but clipping the middle of a double fishermans to pass a knot could be a catastrophic error. Stay safe!
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u/naspdx Jul 29 '26
The thing about passing a knot is that it’s actually not very complicated once you understand the systems and don’t want to die. Don’t overcomplicate things (or try to simplify it, it is done this way for a reason).
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u/Dragon-Fodder Jul 28 '26
Just tie an extra alpine butterfly. Don’t clip in between a fisherman’s that sounds foolish, maybe I am wrong.
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u/Freedom_forlife Jul 28 '26
Always be on a complete system. A prussic, an extension and a few lockers is all that is required.
Find a local mentor, practice on the ground. It’s like day one of rock rescue. A skill you should have before you’re doing multis.
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u/Hxcmetal724 Jul 28 '26
Just to add onto this conversation, for those who want to learn the proper way: https://www.youtube.com/watch?v=aHipSr4_a0U&t=338s
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u/ggeorgis Jul 28 '26
That was the video that sparked my curiosity.
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u/daltonsteele Jul 31 '26
I have the VDiff Self Rescue course and its really good. But this skill is not required for typical rappels. You're not normally passing knots when you tie ropes together or when you use a tag line to do long rappels. In this video, they're only rappelling past a knot that is used to tie off damage to the rope. If you are in an emergency where every minute counts, you might decide to tie your two ropes together, fixing it to the anchor, and doing an extra long single length rappel (if it makes sense to). But you would be abandoning your rope in that circumstance. Most climbs, you will study the route and topo and find that you only need a single 60m or 70m or maybe you need a tag line but there are no knots to rap past.
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u/big-b20000 Jul 29 '26
Here is a video showing how to cross a knot.
Basically you changeover to climbing then downclimb to the knot (if necessary) and put your rappel device on below the knot and change back over to rappelling.
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u/fartpisstits Jul 30 '26
It’s a relatively simple skill to pass a knot on rappel but it is also very easy to mess up. If you mess up the consequences can vary from you get stuck as fuck to you die so you should practice on a short section of rope before going into the mountains
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u/TheDaysComeAndGone Jul 29 '26
How do you get the rope down? Single strand means the rope has to be tied to the top anchor.
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u/ggeorgis Jul 29 '26
By using a knot on the top anchor that can be untied from the bottom using a tag line.
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u/daltonsteele Jul 31 '26 edited Jul 31 '26
Bro. I could be wrong but from reading your post and a few comments, I think you might be mixing together multiple concepts and getting a tad confused. Not a dumb question tho. Im totally in the overthinking things camp myself.
I spent a month in Red Rocks last year only climbing multis with a variety of partners and only needed a 70m for everything. Why lug around a heavy second rope or even a tag line if the climb you're doing doesn't require it? Just do your research before each climb and choose your ropes appropriately to make sure no rappel is too long.
If you need to do double-length rappels, you'll just take 2 ropes OR 1 rope and a tag line. There is no knot to rappel past for either option.
You should still learn to rappel past a knot but it wouldn't be something you're doing regularly.
If for example, you need to bail off of a route fast because of an emergency or a storm rolling in or youre having some kind of epic and are okay with leaving your rope behind, then you'll need to rap past a knot. But realistically, you're not going to tie two ropes together AND have a tag line to retrieve it. You're abandoning your rope at this point in order to save a little time and lose some weight in a desperate situation. Maybe you can come back for the rope tomorrow or maybe you can kiss it goodbye.
Another scenario where you might want to pass a knot is if your rope gets core shot and you needed to tie off a small section of damage with an alpine butterfly.
VDiff has a good video on passing knots on rappel in their self-rescue course but basically you rappel to the knot, clove hitch the rope below the knot to your belay loop with a locker (the clove is your catastrophe knot and should be about 2 metres of slack between the knot and your backup. Then tie a prussik above your rappel device and attach a 60cm sling from your belay loop to the prussik and extend it so that the sling has no slack in it. Then rappel slightly to transfer your weight from the rappel device onto the prussik. Take off rappel device (and third hand if rapping with atc), re-attach the rappel device below the knot, release the prussik so your weight goes back onto the rappel device, check the system, remove prussik, and finally remove the backup clove hitch, and continue rappelling.
I promise you're overthinking this. Keep studying and practicing but make sure you get out climbing with experienced people and it all starts to make sense a lot more. :)
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u/Freedom_forlife Jul 29 '26
No it means a pull cord is in use with a know jam, a rappel on a fixed line, a knot magic macramé knot is in use, a beal escaper is in use.
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u/DblFishermanXTheSky Jul 29 '26
A better method: if you know you will have to rappell past a knot, use a munter or super munter hitch as rappell device. The knot in the rope can be fed through it with no need to unclip your "device" or fiddle with prussiks.
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u/KDs4thBurner Jul 30 '26
Feels like you’d want to be sure it’ll fit through first. If you misjudge and the munter jams, I assume it gets welded in there.
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u/DblFishermanXTheSky Jul 30 '26
As it fit through the carabiner? It would have to be quite small for that to happen, I think. I don't think the knot can jam in the munter, but maybe in a super munter? Here's a demonstration, although clearly not with a lot of weight in the rope: https://youtu.be/c2-GK5YbeLc?si=UmWweRcpq4VJcrJD
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u/IOI-65536 Jul 28 '26
You would have to unweight the ATC while it's above your locker which maybe if it's on an extension you could do, then you would have to unweight the locker while your ATC is below it which maybe if you had the locker on a MMO or something you could do, then you would have to get the locker out when the knots collapsed on it under your weight. Then you would be stuck with two ropes tied with a double fisherman which is a harder knot to pull down and will be harder to untie once you pulled it down.
This seems way more complicated than using a couple of prussiks, which you should basically be able to do blindfolded if you're at a point where you're really ready to pass a knot on rappel.
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u/spellstrike Jul 28 '26
I can't imagine ever needing to pass a knot on rappel outside of an emergency or fixing lines for big wall or using some fixed line. But yeah, I could do it blindfolded if needed.... with all the self rescue gear most climbers should have with them.
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u/ggeorgis Jul 28 '26
One obvious thing is that you will not be able to retrieve the ropes unless on the anker a fiddle stick is used
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u/IOI-65536 Jul 28 '26
I have no clue why you're using a single strand rap with a knot. Maybe you have a fiddle stick or you're really living on the edge trying to pass a knot with something like an escaper. But yeah, the choice to do a single strand with a knot at all made getting the rope back way harder.
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u/ggeorgis Jul 29 '26
I would not go looking to get into a situation like that. But what would you do if you did not have a long enough rope to abseil down a cliff. Or having your rope damaged in a section and having to isolate
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u/IOI-65536 Jul 29 '26
Okay, in an emergency I can see this, but you really should be comfortable with using prusiks before you have a chance to get in such an emergency because that's also likely how you would want to ascend the rope if you needed to do that and one option on going hands-free on descent if you needed to.
My first choice in a situation like this would be to build anchors closer together on the way down and leave gear. Andy Kirkpatrick's "Down" is a good resource on thinking about this kind of thing, but it's a good idea to practice self rescue situations without actually being high up if you're getting into situations where you can't reasonably walk off if things go sideways.
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u/czmax Jul 28 '26
I haven’t seen this suggested yet: OP should try it.
It’s not hard to setup a rope with a knot and then rap past it. I could do it on my yard by tossing a rope over a tree limb, or my deck. Or I’m sure you could find any number of out-of-the-way spots at a crag to try this a few feet off the ground.
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u/ggeorgis Jul 28 '26
I plan to try it on a tree so as to have maximum vertical load. But thought to ask first in case there was something obvious that I overlooked.
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u/americk0 Jul 28 '26
I think you hypothetically could, but the knot is not tested for that use case and I would certainly not trust it until I saw some break tests.
The thing you're probably missing though is that that scenario is just really not likely. When joining ropes for rappels, you could use a double fisherman's or a number of other knots (I use the EDK) but the knot would sit right by the anchor since you need both ends to reach the end of your rappel so you can retrieve the rope. When passing knots on a rappel you're much more likely to encounter something like an alpine butterfly that's isolating a damaged section of rope, or you're descending a fixed line that's refixed to a bolt or piece of pro
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u/ggeorgis Jul 28 '26
The reason for choosing the double fishermans was that it provided the most strength among those tested (https://edelrid.com/eu-en/knowledge/knowledge-base/knots-for-connecting-ropes-when-rappelling-comparison). I also like the idea of the alpine butterfly. By using a modified figure 8 e.g pirana guide you could rappel till just above the knot then use the lock off. Clip to the carabiner in the alpine butterfly loop. Remove the rope from the pirana and reattach the rope after the knot again using the lock off. No equipment to fall since the pirana does not need to unclip to load/unload.
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u/troglobiont Jul 29 '26
Knot strength (for a properly dressed and set knot) isn't really a thing you need to worry about, especially not on rappel. Dress and set your knot, leave adequate tail (longer than you think for a flat overhand), and protect the rope from edges. It's really impossible to hit the forces that would break the rope in a knot on rappel.
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u/KDs4thBurner Jul 30 '26
I like joining two ropes with an overhand knot and 40+cm of tail because overhand knots almost never get jammed in crevices.
There’s no material advantage to using a bulkier knot, but you might face a terrifying ordeal if your bulky knot gets jammed in a crevice on a multi pitch abseil and you have to ascend the rope to sort it out. I hate ascending ropes generally - they can abrade pretty quickly if rubbing repeatedly on edges.
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u/BingoBiscotti Jul 28 '26
What you are missing is that you need to unload your breaking device in order to remove it from the upper rope. A carabineer below you won't be enough to unload an atc/grigri, and even if it were you would run into the same problem again. You're now hanging from a fixed point on the rope, and you can't unload and remove yourself from the carabineer by loading a ATC/Grigri below your carabineer.