Passing a Knot on Rappel
 

If you know you will be passing a knot during a rappel, you can do so with greater efficiency by pre-rigging. Start by setting up a 2-strand tether on your harness. The long strand of the tether should be just within arms reach. The short strand should be a bit less than half the length of the long one. Secure a locking carabiner to the end of each strand.

Here are some suggestions:

(a) Petzl's Spelegyca (was Energyca) is ALMOST perfect for this. Tie an overhand knot in the short strand to take out a bit of the length and it becomes perfect.

(b) Use a daisy chain as the long tether and a canyon quickdraw as the short one. Using a daisy, you also have the option to forego the short stand and simply use a carabiner clipped to your harness instead. I'm not a big fan of the long daisies sold in climbing stores. Prefer a 2-foot daisy. Got mine directly from BlueWater.

(c) You can make your own tether with 8 or 9 mm rope or cord. There is a good illustration in "On Rope".

PRE-RIGGING
Rig your rappelling device on the rope. Above your rappelling device, attach a Shunt or a prussik to the rope. Clip the long strand carabiner to the Shunt/prussik. Check the length to be sure you will be able to reach it and operate it later. Once you are sure the length is correct, clip the short strand carabiner to the long strand carabiner. If you are using a daisy chain, you can clip into one of its loops instead. You will also need a second ascender/prussik with foot loop. Ensure that it is handy. Begin your rappel, bringing the Shunt/prussik down the rope with your non-brake hand.

PASSING THE KNOT
Stop when your brake hand reaches the knot. Lower yourself a bit more. Goal is for the knot to be within about 6 inches from your rappelling device when you allow the Shunt/prussik to take your weight. Too close and the knot may jam in your rappelling device. Too far and this technique won't be as efficient as it could be. Now follow these steps:

(1) With your weight now on your Shunt/prussik, remove your rappelling device from the rope and re-rig it below the knot. LOCK IT OFF.

(2) Rig your foot loop ascender on the rope between the knot and your Shunt/prussik.

(3) Stand up in your foot loop and unclip the short tether strand carabiner from the long strand carabiner (or daisy chain loop). Lower yourself until you are weighting either the rappel rope or the long strand of your tether.

(4a) If the tether strands are set up at perfect lengths, you may already be weighting the rappel rope. All you need to do now is remove your Shunt/prussik and your footloop ascender, unlock your rappel device and continue.

(4b) If you find yourself weighting the long tether you will need to stand up in your foot loop again. Release the Shunt/prussik and bring it down until you are weighting the rappel rope. Now remove your Shunt/prussik and your footloop ascender, unlock your rappel device and continue.

Practice this technique at the local crag BEFORE you head out to the canyons.

Have fun. Be safe.

Rich

Another method
 

Experimented last weekend with quick systems for passing a knot and here's how it went.

- tied ropes together using figure eight knot, but on the top rope end, used a eight-on-a-bight then rethreaded the bottom rope through this, thus creating a bight of rope at the knot. This is for clipping a safety in to.

- Prepared myself with a footloop clipped to an ascender and two slings & locking carabiners hitched to my harness (safety lanyards - pair of cowstails would also do fine).

Simplest system I've used.
1.) Rapped down to the knot and allowed it to jam in my ATC.
2.) clipped in my first safety to the bight at the knot.
3.) Placed ascender on rope.
4.) clipped 2nd safety to rope above ascender (jams at ascender) - also could clip directly to ascender.
5.) stand up in foot loop and (this was the hardest part, as I was freehanging) unclip ATC from rope

at this point I'd like to hear some experience. Is there a way to make it easier to get slack in the rope to unclip your belay device? It's a challenge to hold yourself in the standing position with one arm (holding the ascender) while trying to unclip your descender one handed or with both hands if you're able to akwardly wrap your other arm around the rope to hold yourself upright.

6.) reattach belay device to rope.
7.) unclip ascender safety and ascender.
8.) unclip bight safety.

9.) Continue rappel to the ground.

The whole process probably took less than three minutes without practice. Both myself and a relative newbie friend did it easily in this time. Seemed an improvement over systems I had seen that took as much as 15 minutes.
I recommend and enjoy.
Anyon

newbie question but couldn't you just take two belay devices and attach one below the knot before disconnecting the one above?

You've dug up a thread from 2004.

Yes, you could use two rappel devices, but you still need to shift your weight from the one above the knot to the one below the knot.

I have simplified my own knot passing technique: Pre-rig a VT Prusik (valdotain) on the rope above the rappel device. Pull it with you until you are just above the knot and let it grab to hold you. Remove your rappel device from above the knot and move it below the knot. Lock it off. Pull down on your VT Prusik and lower yourself onto your rappel device. Remove the VT Prusik. Continue rappelling.

I love this method!!! Slick and easy. Requires practice to get the pull-down pressure right for lowering off the valdotain... The first couple times you might get a little surprise :yikes:.

You MUST connect to your VT Prusik using a short tether (i.e. short side of Spelegyca). You MUST re-rig your rappel device immediate below the knot -- AS CLOSE AS POSSIBLE. If you don't follow this advice ...

When you pull down on the top of your VT Prusik to release it, you might get a little surprise -- a quick drop. Won't be a problem unless it comes down hard on top of the knot. This shouldn't happen if you follow the advice above.

Alot of you may know this one already but for the newbies, one other method is to not pass the knot. Rig your rappel device just below the knot joining the ropes. The knot should also be at the top of the drop just after a lowering system. This can be either a munter or a figure 8 contigency block or use the ultimate device the Totem. Lower each person until the first rope just touches the ground. At that point stop lowering and lock off your lowering system. Person on rope now raps the rest of the way to the ground.
It's probably faster to do this than waiting for each member of the group to fuddle with passing the knot. Last person down will have to pass the knot unless you can master lowering someone from the ground. This is an even more advanced technique.
Dave

I'll add ...

We discuss ways to pass a knot, but it is extremely rare. Why do we need to pass a knot?

(1) Rope has a core shot. Tie an alpine butterfly so the core shot is in the loop.

(2) Rope is too short and must be tied together to reach the bottom. ?? Think this one through. If one strand is long enough, we can rig a block and put the knot on the pull side. If we need to tie a knot in both strands, we will have a retrieval problem.

(3) Prefer avoiding a multi-pitch rappel, at least for the majority of the group. Tying two ropes together and using the system Dave described will allow everyone but the last person to avoid the multi-pitch.

I can think of only 1 way around this but it's quite complicated.

Simplest way is to rig a retrievable; i.e. macrame. That would mean passing a knot while hanging on a retrievable.