Half Rope (double rope) lead belay using 2 lockers for added friction

I'm sure most people are aware of the option to add friction to a rappel using 2 biners, however, I've never seen it advised for adding friction to skinny doubles with a weight difference in the leader and belayer. Currently the belay device being used is a Reverso 4, which is pretty well designed for thin ropes but the weight difference between belayer and leader is 80lbs fully racked.

Is there any reason this is a fundamentally bad idea? I assume feeding might be a bit more work, but it should feed well enough (this is easy enough to test).

I can't really think of any reason this would be unsafe or flawed, but I'd rather be 100% certain before I test this in the wild.

Thanks.

I used to use two O&O 'biners with a Stitch plate and single rope when belaying.

Not specifically to increase friction but because the rope didn't jam like it did with one carabiner. I don't know why it wouldn't work with an ATC or Reverso.

This is becoming increasing common when using thin ropes. It would be good to see it discussed by the manufacturers. The two lockers need to be identical in size and both need to be clipped to the belay loop.

Here's a photo.

(from multipitchclimbing.com)

and here's how not to do it.

(from multipitchclimbing.com)

David Coley wrote:This is becoming increasing common when using thin ropes. It would be good to see it discussed by the manufacturers. The two lockers need to be identical in size and both need to be clipped to the belay loop. Here's a photo. (from multipitchclimbing.com) and here's how not to do it. (from multipitchclimbing.com)

Thanks, David. I've often referenced Andy Kirkpatrick as a resource, so I feel pretty comfortable now.

Looks like a great book. Any reason it's not on Google Books or Nook? I don't use Amazon due to the proprietary nature of it's books. Don't have an Apple device, and haven't ever used Kobo (will check it out though).

David- Do you know why they have to both be clipped to your harness? and be the same size, orientation and type?

I have not done this, but its hard to think of a reason why it matters. Come to think of it, why is it necessary for the second biner to be locking at all?
Thanks!

Both the biners need to be clipped to the belay loop. The idea is to spread the rope so it has more rope on metal contact. The larger radius around the biners and more contact with the belay device.

If you don't clip the second biner to the harness it will for up above the other biner and negate the effect.

Based on what wivanoff said, it might actually feed better while also providing more friction when locked. Seems like a win win.

I guess we'll find out if that is the case with the reverso vs a stitch plate.

Thanks for all the insights.

I think it makes sense and don't see any issues with a Reverso, ATC-XP, or similar devices. Do not, however, try two carabiners with any of the assisted lockers, at least not in assisted locking mode, which will be compromised.

The only problem might be pumping slack to the leader. Having a Reverso or XP grab in that situation usually means the belayer needs to bring the brake strand up more nearly parallel to the load strand so that the angle between the two doesn't force the plate down onto the carabiner. I'd guess if there are problems, a small adjustment in hand movements would take care of them.

P.S. The Coley-Kirkpatrick book belongs on every climber's reading list. Most internet controversies have already been settled in it.

J. Serpico wrote: Thanks, David. I've often referenced Andy Kirkpatrick as a resource, so I feel pretty comfortable now. Looks like a great book. Any reason it's not on Google Books or Nook? I don't use Amazon due to the proprietary nature of it's books. Don't have an Apple device, and haven't ever used Kobo (will check it out though).

Possible because I'm not very good with IT and I have a full-time job. Amazon gets a lot of bad press, however, for the author it is very good. An author will get around 70% of the cover price. With a normal publisher it would be about 10%. It is interesting that this doesn't often come up in the press.

matt c. wrote:David- Do you know why they have to both be clipped to your harness? and be the same size, orientation and type? I have not done this, but its hard to think of a reason why it matters. Come to think of it, why is it necessary for the second biner to be locking at all? Thanks!

As another poster indicated, the two lockers make a bar that is wider than the hole in the plate. This creates a lot of friction. This bar will only form if both lockers are clipped to the belay loop. If only one is clipped then rather than sitting next to each other, they sit one on top of the other. This will greatly reduce the amount of friction, and you would not be able to hold a fall. (It is however a great way for a light person to rap on an old fat 11mm).

The second carabiner doesn't need to be a locker, but as it needs to be close in size to the locker, it probably needs to be a locker.

J. Serpico wrote: Thanks, David. I've often referenced Andy Kirkpatrick as a resource, so I feel pretty comfortable now. Looks like a great book. Any reason it's not on Google Books or Nook? I don't use Amazon due to the proprietary nature of it's books. Don't have an Apple device, and haven't ever used Kobo (will check it out though).

I forgot to say, that even if you don't buy the book you are welcome to view and use all the images connected with the book. (the images aren't in the book because there are 1000+ of them.) Just visit multipitchclimbing.com

The images in the HTML version are very small, the ones in the pdf's much larger, so I recommend the pdf's.

(PS. If anyone knows how to get WORD to not shrink the images when it spits out HTML, please let me know. Thanks.)

J. Serpico wrote:I'm sure most people are aware of the option to add friction to a rappel using 2 biners, however, I've never seen it advised for adding friction to skinny doubles with a weight difference in the leader and belayer. Currently the belay device being used is a Reverso 4, which is pretty well designed for thin ropes but the weight difference between belayer and leader is 80lbs fully racked. Is there any reason this is a fundamentally bad idea? I assume feeding might be a bit more work, but it should feed well enough (this is easy enough to test). I can't really think of any reason this would be unsafe or flawed, but I'd rather be 100% certain before I test this in the wild. Thanks.

Guess your a bit young then, it was shown back in the early 70´s for the Salewa Sticht plate, they gave a force increase of about 80% but we know now this is a bit variable.
I´ll publish some numbers on the effect with modern plates when I´ve finished some other testing but sure it works, especially with thin ropes.