Tech Tip: Question "double rope " = unequal how do you get down ?

prompted by discussion on another thread , the most usefull response i can muster = this thread

senario - an abseiler is on double rope [ specify how its anchored ] - using device [ specify ] , descending a 40m pitch . the rope = 100m [ you know for certain that both figures are true ] , but for " reasons " one strand = 15m short of the pitch bottom . there is no damage to the rope - nor is the " extra " tangled or trapped

you have no other ropes

you are either the abseiler - or at the pitch head - with extra equipment [ specify ]

how do you get your self or your friend to bottom ??????????

Let's assume worst case. You're the last one down, (I know, I know, so let's say you're solo) there is no ledge to stop on and no intermediate anchor. You've still got a couple of options. One is to ascend and rig it properly. This might be the best solution. The other is to flail around a bit by locking off the short strand and continuing. That might require force feeding rope through your device, depending on the device. If you do this, hopefully you're not rapping from a single, half sawn-through aluminum rap ring on a wet sandy rope. That was probably obvious, but ... since you're being really careless while soloing, I thought I should mention it.

Whilst on rappel with my trusty ATC, I brake one strand and continue rappel until I can see the strands equalize at the bottom.

Assumes the rope is through a fixed anchor and not fixed.

Done it a bunch. Easy peazy lemon squeezy.

Rig the rope in a way that isolates both strands. a stone knot works if you dont know which side is longer. Wtih a rope bag, I can typically hear a nice thud so I can do something like a biner block to make the rope bag side static. first person down can tell me how to adjust if the other side is not long enough.

Just for variety's sake...you clip your Pantin (or MT) on the short strand and step, step, step to a happy-equilibrium. (Similar to Brian's solution.)

Yeah, ATC easy peasy. Figure-8 type devices can be tougher, depending on rope diameter, fuzziness, stiffness, size of device, load, etc. Lots more scenarios where you have to force feed the device.

I've actually tried the atc method, both ends were on the ground, just wanted to see it in action. Apparently there was enough friction of the ropes going up over the rock and to the anchor that it didn't want to feed at all. Now I've never been trained in this method so it's possible I was doing something wrong, but it's not exactly a complicated procedure so I'm not all that sure what I could have screwed up.

Probably nothing. I did it once with a Piranha, on a slightly less than vertical drop with the rope contacting the rock up above. It was a real booger to stuff the long side through that thing. Kuenn's idea looks better and better ...

I appreciate the endorsement and it does work, however reducing friction on the long strand is the name of the game.

To illustrate this I created a short video highlighting 2 different descending devices (ATC and Sqwurel) DRT simulating one side short rigged. The final test is the method I proposed above. If the conditions are favorable (what we can create in dirty garages), then Brian's (SLC) method is truly "easy peazy" and the hands-down no-hassle solution.

If friction variables are not favorable, then the method I proposed will offer a last-ditch effort.

For your entertainment...

An ounce of prevention is worth a pound of cure.

Tom

True that.

A quote from days long past comes to mind. I recall Kwai Chang saying (although he obviously didn't coin it), "trust, but expect the unexpected". And be ready when it comes.

Maybe the most important thing to remember in a short rigged DRT scenario is situational awareness and don't escalate the problem.

Very true. More haste, less speed. Some of us had to learn that the hard way. It happened to me on a "short" "easy" drop where we were under time pressure. The drop turned out to be longer than expected, rolling off at the bottom. I found a marginal ledge to use to take enough weight off of the rope that I could manually feed it through as Brian's trick had no play at all with the figure-8 and my rope. It wasn't the safest procedure in the world and I can't recommend it. The time "wasted" by equalizing the ends before tossing would have been paid back with interest.

The nice thing about this community is the ability to learn from the mistakes of others rather than making them all on your own. Another example for me is the helmet thing. We never wore them. I still hate my old MSR salad bowl of a helmet. Then one day a friend took a fall that could have been serious had he hit his head rather than his shoulder. Hmmm. That was just after the introduction of the lightweight climbing helmet from Petzl modeled on cycling helmets and we started wearing them. Now you get a ration if you post a picture without. Oh yeah, the girth hitching of a figure-8 while going over an edge. Been there, done that, too. The list goes on. Having resources to learn from is a really good thing. In some ways, I wish I could have learned stuff in the modern way. But I also have some great memories of discovering easy scenic canyons with no footprints in them and I wouldn't trade that for the world. The internet is very much a two-edged sword, but it exists and it won't be going away, so not using the edge that helps you is silly.

We can start this up again.

Easier just to start off using single rope

Ok. You're rapping down on your single rope. You look down, mid rappel (give or take) and discover that your rope is too short.

Now what?

Pretty rare to see folks rig for contingency with a single rope rappel. They block the rope and rap single. I know Tom has touted being able to convert to a lower fairly quickly. How many folks could effectively do that? Especially with a "live" load hanging on the rope?

Anyhow...worthy of its own thread, perhaps. And, not the OP's situation we were originally presented with.

Top: How short?
On rope: Looks like 40-50 feet - hard to tell.
Top: I've got that much coiled. I think I can rig a covert to lower.
On rope: (voice trembling) YOU THINK??
Top: Chill, dude! I learned it from the best, super easy... Canyon Collective no less!
On rope:

(My apologies to the OP, couldn't resist.)

or the modern version:

Top: How short?
On rope: Looks like 40-50 feet - hard to tell.
Top: I've got that much coiled. I think I can rig a convert to lower.
On rope: (voice trembling) YOU THINK??
Top: Chill, dude! I got the vid on my phone, right here. Let's see... Cats, no. Dogs, no. Beluga whales... ha ha ha ha ha... Okay, here we go, ropework!
On rope:

T

some good points - BUT with devices that have a " shared pathway " - you have a moving rope in contact with a static rope

thats NOT good

Maybe "not good" as standard procedure, but this thread topic is NOT about standard procedure. It is, in fact, how to recover from a screw-up.

we use a model called the incident pit - to convey how multiple failings compound

the way you " reccommend " - there is the posibility of creating a sheath failure on a rope thats STILL too short - so much for recovering from screw ups

securing the " short strand " ABOVE the descender device - at least eliminates the threat from internal friction in the device

an ounce of prevention is worth a pound of cure.