Double Rope Rapping with a GriGri.

I know that the manufacturer says it's safe for single rope rappels and not to exceed 50m. I think a lot, far too much in fact, most of the time it's about women or climbing, I'm starting to be concerned as the balance has tipped more towards climbing, anyway I'm getting off topic.

What I was thinking and I'm sure I'm not the first to think this but if you needed to double rope rap on a GriGri, couldn't you go about things like normal, thread the rope through the chains like normal then proceed to tie a knot in the rope, lower off the side of the rope you didn't tie the knot in and pull the rope down from the side you tied it in?

Not saying this is safe, not saying I plan to try it, I was just thinking and it dawned on me it would work so I was wondering if anybody has had to do anything along those lines?

Yeah, blocking the knot up to the chains will work, but I personally don't feel great about the idea.

I'd preffer to tie a bight into the side you tied the knot in and clip it to the rappel side, creating a closed sytem. Of course, this icreases chances of a stuck rope. Which one I used would depend on the terrain and type of chain anchors I was going through.

Evan

The GriGri is not the best multi-pitch device. Its heavier than a regular ATC, and with the guide or reverso you get auto-locking in guide mode. It will also give you issues if you ever want to lead on double ropes. Leave the GriGri to single pitch climbing. If you must use it, like you said you can rappel by knot or carabiner blocking the rap rings. This puts a lot of stress on the knot and single rope. Or you can tie back in and essential lower yourself.

Why bother using a GriGri? Why not just carry a small tube device for the raps or if that is "too heavy" just use a Munter hitch. Jamming two ropes in a GriGri doesn't sound like a good idea.

Or you can clove hitch a locking biner on the spine and block that against the chain anchor - provided the biner is large enough. This backs up the knot.

+1 on the simul-rappel, especially when rapping off of bomber chains. Its the way to go

TomCaldwell wrote:The GriGri is not the best multi-pitch device. Its heavier than a regular ATC, and with the guide or reverso you get auto-locking in guide mode. It will also give you issues if you ever want to lead on double ropes. Leave the GriGri to single pitch climbing.

The Gri-Gri is also auto-locking in guide mode, and feeds much more smoothly than either the ATC-Guide or Reverso.

And you can haul a second with a Gri-Gri more easily than with those devices.

And the OP might have been thinking of using the Gri-Gri to self-belay (which is not recommended by Petzl, but is a pretty common practice).

The Gri-Gri is my favorite multi-pitch device.

TomCaldwell wrote:If you must use it, like you said you can rappel by knot or carabiner blocking the rap rings. This puts a lot of stress on the knot and single rope. Or you can tie back in and essential lower yourself.

Don't do this if the rope is through rap rings, or even worse, if it is through just slings! That is a recipe for disaster.

@OP: I use Evan's setup---tie a Figure-8 on a bight between the knot and the chains, put a locking carabiner on this loop and run the other side of the rope through this locker. This creates a closed loop (similar to a girth hitch) and doesn't put any pressure on the knot joining the two ropes.

Note that this doesn't even depend on the knot joining the two ropes. You can use it on a single-rope rappel also. Alternatively, you can use this setup on a double-rope rappel where your pull cord is very small (not big enough to rappel on).

Another note: obviously you can use this for other devices as well, including ATCs and Reversos.

This is from the GriGri manual:

Regarding double rope rappels:

If you do it right there is nothing wrong with rapping a single line on a gri gri, cinch or any other rappel device using only a stopper knot joining two ropes. Tying another knot and clipping back to the other side is not necessary if your stopper knot is adequate. But, some people feel more comfortable "closing" the system.

If both ropes are suitable for rappeling simul rapping may be the way to go as Beached Nuts mentioned regarless of the device you choose.

Greg D wrote:Regarding double rope rappels: If you do it right there is nothing wrong with rapping a single line on a gri gri, cinch or any other rappel device using only a stopper knot joining two ropes. Tying another knot and clipping back to the other side is not necessary if your stopper knot is adequate. But, some people feel more comfortable "closing" the system. If both ropes are suitable for rappeling simul rapping may be the way to go as Beached Nuts mentioned regarless of the device you choose.

It really freaks me out that so many people are not aware of the failure in knot tests with cinch and grigri's. This is the number one way to get your device to fail. I am pretty sure the loads were around 7-9kn for both devices. Knots pulling into the devices splitting them open and disengaging from the rope.

Also, I really hope you are not talking about rapping an 8mm rope as that combined with a knot at the bottom is just asking for it.

SAL wrote: It really freaks me out that so many people are not aware of the failure in knot tests with cinch and grigri's. This is the number one way to get your device to fail. I am pretty sure the loads were around 7-9kn for both devices. Knots pulling into the devices splitting them open and disengaging from the rope. Also, I really hope you are not talking about rapping an 8mm rope as that combined with a knot at the bottom is just asking for it.

I didn't mention rope diameter. I guess I assumed those that use gri gris and cinches have an idea of minimun rope diameter for their device.

As far as generating 7-9kn while rapping and knot failure? 7-9kn while rapping means you've done something else wickedly wrong. And how does any particular device lead to knot failure? Please clarify.

Greg D wrote: I didn't mention rope diameter. I guess I assumed those that use gri gris and cinches have an idea of minimun rope diameter for their device. As far as generating 7-9kn while rapping and knot failure? And how does the device lead to knot failure? Please clarify.

yeah the OP did not list diameteres of the doubles but i'd have to guess that the point of doubles is saving weight and full length raps. Thus being sub 9mm. If he is climbing on double 10mm's then well this all just seems silly.

First. I did not say the knot will fail. I said the device could fail becuase of the knot.
The knot test is a pretty simple test. An knot is tied in the rope. Device slips and knot gets yarded into the device. both devices split open. I am sure it can be debated the KN generated when rapping and being able to hit that marker.A Given we are talking about "double ropes" here i just imagine someone whipping down an 8mm cord. hitting teh knot. then the ground. A prussik above your grigri or cinch woudl be a much better way to back up your rappell in my opinion.

Greg D wrote: I didn't mention rope diameter. I guess I assumed those that use gri gris and cinches have an idea of minimun rope diameter for their device.

hehehe. Not too many people abide by the recommended diameters with the grigri. Cinch is a bit wider. I actually just had someone drop me about 15 feet with a grigri last weekend before it locked up. This was on a 9.9mm cord. I'd imagine if there were a knot tied towards the end of that ride it could have generated some pretty good force.

SAL wrote: yeah the OP did not list diameteres of the doubles but i'd have to guess that the point of doubles is saving weight and full length raps. Thus being sub 9mm. If he is climbing on double 10mm's then well this all just seems silly. First. I did not say the knot will fail. I said the device could fail becuase of the knot. The knot test is a pretty simple test. An knot is tied in the rope. Device slips and knot gets yarded into the device. both devices split open. I am sure it can be debated the KN generated when rapping and being able to hit that marker.A Given we are talking about "double ropes" here i just imagine someone whipping down an 8mm cord. hitting teh knot. then the ground. A prussik above your grigri or cinch woudl be a much better way to back up your rappell in my opinion.

Ok, that makes a little more sense. But, if you are rapping down so fast that a stopper knot splits your device open you probably end up with the same fate as with no knot. But, to generate large loads rapping you would have to be zipping down in some sort of crazed cowboy gone sport rappeling with a cigarette hanging out of your mouth style, then suddenly hit the "brakes". Possible, I guess.

SAL wrote: hehehe. Not too many people abide by the recommended diameters with the grigri. Cinch is a bit wider. I actually just had someone drop me about 15 feet with a grigri last weekend before it locked up. This was on a 9.9mm cord. I'd imagine if there were a knot tied towards the end of that ride it could have generated some pretty good force.

I had the same thing happen. 9.4 on a gri gri. My partner thought it would be convenient to use since we were just cragging. What should have been a 5 footer turned 15 footer. I had never used one and didn't know much about em. . I do now.

But, now we are talking about falls (lead or tr). Quite different from the op's question about rapping.

Greg D wrote: I had the same thing happen. 9.4 on a gri gri. My partner thought it would be convenient to use since we were just cragging. What should have been a 5 footer turned 15 footer. I had never used one and didn't know much about em. . I do now. But, now we are talking about falls (lead or tr). Quite different from the op's question about rapping.

actually mine came when being lowered to the ground :) :)

Greg D wrote: Ok, that makes a little more sense. But, if you are rapping down so fast that a stopper knot splits your device open you probably end up with the same fate as with no knot. But, to generate large loads rapping you would have to be zipping down in some sort of crazed cowboy gone sport rappeling with a cigarette hanging out of your mouth style, then suddenly hit the "brakes". Possible, I guess.

possible for sure.

Were discussing in the event of failure or loss of control though right? the ol what if. Another point is that with "autolocks' suck as the grigri the natural instinct for people is to keep holding on. SQUEEAE tighter. NOT let go. so if the person did start screaming down the rope chances are they may not let go and engage the device before that back up comes to get ya.
my point really is that if you are using a back up it is becuase you think you could possibly lose control and start sliding out of control or lose your break hand. I just want to see people use back ups that will actually work if said epic did happen. I just dont think enough folks know about these tests and using a knot as a "backup" may not be the best idea.

I didn't have any real thoughts in mind with my post, not something I planned to do just wondering if I could. What I was more so wondering was provided the knot wouldn't pass through the chains (of course you wouldn't do this with rap rings or a sling) I was figuring you could maybe still use an atc to rap off on both ropes but the grigri as a back up on the single line. You would have to extend your belay device with a sling and I don't know if the grigri would lock too easy but it seemed like it would work and keep pressure off the knot up top.

Like I said, I wasn't planning on even doing this, sometimes I will rap really slow so I can take pictures of friends climbing and so on, was just thinking of ways to make that safer and easier. I could of course just use the grigri and a single rope but where's the fun in doing what you know.

And of course the rope would have to be the right size and not totally new and shinny, the grigri doesn't do well with thin rope, and for some reason it never cams when I thread it with a sling instead of a rope, the manual says nothing about not using them with slings, it really should though.

If you are just wanting to back up a rap, one of the preffered methods is adding a prussik around the brake strands below your ATC, attached to your thigh loop.

This is far easier and better that adding a grigri into the system.

Two tips:
1. exend your atc off your harness with a sling or PAS or daisy chain(clip the correct way).

2. put the prussik on the brake strands before rigging your atc. This will take the weight of the rope off, making you less likely to bumble your atc.

Evan

Thanks Evan, I'm familiar with that, again, I was just thinking, too much clearly and figured I'd ask, I've been fine just tossing the rope around my leg a few times, that isn't a back up but it suits my needs when I wanna stop for long amounts of time.

Guess I could also tie a 50 pound weight to the bottom of the rope and pick it up every time I wanna move. That would keep me safe and give my arms a work out.

Adam Block wrote: I know that the manufacturer says it's safe for single rope rappels and not to exceed 50m. I think a lot, far too much in fact, most of the time it's about women or climbing, I'm starting to be concerned as the balance has tipped more towards climbing, anyway I'm getting off topic. What I was thinking and I'm sure I'm not the first to think this but if you needed to double rope rap on a GriGri, couldn't you go about things like normal, thread the rope through the chains like normal then proceed to tie a knot in the rope, lower off the side of the rope you didn't tie the knot in and pull the rope down from the side you tied it in? Not saying this is safe, not saying I plan to try it, I was just thinking and it dawned on me it would work so I was wondering if anybody has had to do anything along those lines?