How to increase friction on a quickdraw?

Got another idea to toy around with, although it's very complicated and you should just buy an ohm instead:

Clip the first draw with a sling with two biners but only clip one of the biners

clip a locker to both biners and tie a tag line to it.

The tag line redirects through a ground anchor and goes to the belayer

When the belayer gets pulled up, the tag line gets tensioned which squeezes the rope between two biners kind of like a garda hitch

I haven't read the whole thread but I do hope someone else has already pointed out that intentionally adding friction to the system reduces available rope to stretch and can significantly increase the forces on climber and top gear during a leader fall.

Seems like the common sense/practices already in place solve this "problem", and I would definitely discourage adding friction by clipping nearby routes... The rope needs to be free of such shenagians to properly do it's job.

Northeast Alpine Start wrote:

I haven't read the whole thread but I do hope someone else has already pointed out that intentionally adding friction to the system reduces available rope to stretch and can significantly increase the forces on climber and top gear during a leader fall.

That is a really good point you are making. Of course, the question was raised in the context of mitigating belayer/climber weight differences.

Consider two scenarios:

A. Belayer, 100lb heavier than climber, gives a catch, no friction added to the system.
B. Belayer, 100lb lighter than climber, gives a catch, friction added via Ohm.

How much less is there available rope in scenario B? Would it be significant?

PS. Yes, many people suggested using slings/bags/anchors/thought/prayers to mitigate the weight disparity - 

Of course you could just take your Silent Partner with a single wrap round the drum instead of the clove hitch. That should work perfectly  

David Kerkeslager wrote:

I'm often belayed by a climber who weighs a lot less than me, and it would be helpful to have and Edelrid Ohm or similar. However, the Ohm runs $130 which seems pretty steep for what it is.

I've seen lots of different ways to belay with carabiners, or increase friction on an ATC style device with carabiners. I was wondering--is there a way to do a similar thing with a quickdraw? Preferably, like the Ohm, it wouldn't significantly increase rope drag unless there's tension from the belayer. I tried out some ideas at home with a quickdraw and an extra carabiner but they are all kind of fiddly and seem like they'll increase rope drag.

RE. your statement earlier in this thread that the people answering you were giving "irrelevant" answers to what you termed as an "engineering question." Above is your original post. Looks like a technique question to me. If you wanted engineering ideas you should have asked more clearly. 

AndrewArroz wrote:

RE. your statement earlier in this thread that the people answering you were giving "irrelevant" answers to what you termed as an "engineering question." Above is your original post. Looks like a technique question to me. If you wanted engineering ideas you should have asked more clearly. 

Any ambiguity in the original post has been clarified by now, and people who have read the thread are still encouraging me to do what I'm already doing.

I see how I could have been more clear with my question (and I'll try to be clearer in the future), but clarity has not solved the problem.

EDIT: I edited the original post for clarity, we'll see if that helps.

Jack Servedio wrote:

What about using a locker on the rope side of the first draw and do full wrap through it? A single wrap shouldn't add too much friction but add a little under load. Or two lockers with the rope wrapped around top of both and out between them so they pinch when loaded?

If I'm understanding your first idea, that's essentially backclipping. I'll give the second one a try though.

This all seems silly though when you can use a tried and true method or just shell out the hundred bucks. 

Climbing seems silly when you can stay safely on the ground.

David Kerkeslager wrote:

Any ambiguity in the original post has been clarified by now, and people who have read the thread are still encouraging me to do what I'm already doing.

I see how I could have been more clear with my question (and I'll try to be clearer in the future), but clarity has not solved the problem.

EDIT: I edited the original post for clarity, we'll see if that helps.

Definitely more clear now.

It's always questionable to assume that everyone reads every post and all the drift of a thread. Many people could easily be just reading post 1 and responding directly to that.

David Kerkeslager wrote:

If I'm understanding your first idea, that's essentially backclipping. I'll give the second one a try though.

Climbing seems silly when you can stay safely on the ground.

It's not just back-clipping - it's a full wrap around the spine of the locker like this:

You might be better off putting the locker right on the bolt so the draw doesn't get lifted - or even using a rap ring or something, but either way it's going to add friction in both directions

And climbing is silly...

Jim Titt wrote:

Of course you could just take your Silent Partner with a single wrap round the drum instead of the clove hitch. That should work perfectly  

Hmm...I think this is the best idea on here

rockhard wrote:

Hmm...I think this is the best idea on here

I'm going to venture a guess that the OP doesn't own a Silent Partner. And in the event that he can buy it (i'm not even sure it is available for sale anymore) it will cost him more than an Ohm, and would work less well than an OHM.

The suggestion above (with wrapping the rope around the spine of the locking 'biner) attempts to do the same thing. OP will experiment with it, I am sure.

Lena chita wrote:

I'm going to venture a guess that the OP doesn't own a Silent Partner. And in the event that he can buy it (i'm not even sure it is available for sale anymore) it will cost him more than an Ohm, and would work less well than an OHM.

The suggestion above (with wrapping the rope around the spine of the locking 'biner) attempts to do the same thing. OP will experiment with it, I am sure.

Yep. Although I may try to get a Silent Partner at some point.

David Kerkeslager wrote:

If I'm understanding your first idea, that's essentially backclipping. I'll give the second one a try though.

The second one is essentially a garda hitch which will make it impossible to take in slack. You can do the same thing but make it only occur when loaded, but it'll be very complex including a ground anchor. Look at my last post for how to do this. If I have time, I might construct this and take photo when I get home tonight.

eli poss wrote:

The second one is essentially a garda hitch which will make it impossible to take in slack. You can do the same thing but make it only occur when loaded, but it'll be very complex including a ground anchor. Look at my last post for how to do this. If I have time, I might construct this and take photo when I get home tonight.

Yeah I set this up to take a picture (like I did wrapping the spine) then realized this was stupid when I couldn't pull slack either way - so I didn't post a picture. Adding friction in general is easy, but adding it in only one direction is hard. Which is why Edelrid charges $130 for it.

Jack Servedio wrote:

Yeah I set this up to take a picture (like I did wrapping the spine) then realized this was stupid when I couldn't pull slack either way - so I didn't post a picture. Adding friction in general is easy, but adding it in only one direction is hard. Which is why Edelrid charges $130 for it.

eli poss wrote:

Clip the first draw with a sling with two biners but only clip one of the biners

clip a locker to both biners and tie a tag line to it.

The tag line redirects through a ground anchor and goes to the belayer

When the belayer gets pulled up, the tag line gets tensioned which squeezes the rope between two biners kind of like a garda hitch

This makes it only add friction in a fall when the rope is weighted enough to move the belayer. But if you're already built a ground anchor (or substitute with a backpack full of rocks), then why not just do that. 

EDIT: Also, what if you had a garda hitch on the first bolt and whipped onto the second bolt. You're essentially lead rope soloing with the first bolt as your ground anchor and taking a high energy fall without a screamer... Not good methinks 

Jack Servedio wrote:

Adding friction in general is easy, but adding it in only one direction is hard. Which is why Edelrid charges $130 for it.

Not only that, apparently the idea of the Ohm is that it adds very little friction whenever the rope runs slowly, and significantly more when the rope runs fast. I remember some video where they explained that a fall causes the Ohm to be pulled up, and this is what actually causes it to (semi) lock up.

It seems hard to replicate indeed. For the "pulled up" part, one idea is to make a quickdraw with one of these anti-cross-loading carabiners at the bottom, such that the rope runs through the part that is usually attached to the belay loop. And then add just the right amount of stuff there so that the rope will drag the biner up when pulled quickly but not when pulled slowly.

And then attach something to add friction whenever the biner has been dragged up and thus flipped. Seems difficult unless you are willing to modify gear.

eli poss wrote:

This makes it only add friction in a fall when the rope is weighted enough to move the belayer. But if you're already built a ground anchor (or substitute with a backpack full of rocks), then why not just do that. 

EDIT: Also, what if you had a garda hitch on the first bolt and whipped onto the second bolt. You're essentially lead rope soloing with the first bolt as your ground anchor and taking a high energy fall without a screamer... Not good methinks 

Oh, I fully agree - both the things I mentioned were just ideas and both stupid in practice. There is a good reason people don't do them. I am extremely light (145lbs) so when I am climbing with taller guys who aren't malnourished, I am fairly frequently outweighed by 40-50lbs, sometimes more, and I've never had a problem that can't be solved with my end of the rope or a cordelette and a couple biners.

However, as an engineer, I can appreciate what David is asking, even if it is pointless in the real world, since solving engineering problems related to climbing can be fun. It's how new stuff is invented.

ok, i'll bite.

the problem is you want there to be no friction when the draw is facing down or i guess close to horizontal. you want there to be increased friction when the draw angle is above horizontal.

that's how the brake strand of a tube style device works. i'm not sure of a way to rig it right now that could work, but maybe a quick draw with an atc on the rope biner? I mean, it's basically the same idea as Jim's munter on the first draw, but you might be able to better control the amount of friction applied to a moderately tensioned rope by adding some sort of spacers between the atc and the biner.

honeslty, i think the ohm is a pretty simple design (though i haven't seen one to confirm) that you could probably reproduce if you have access to a machine shop. i think it's basically just a v that is wide on the carabiner side and narrows on the rope side, so that when the rope pulls hard away or up from the biner, it' slots in the v and adds friction. the spacial negative of an offset nut.

another idea is having two different length draws on the first bolt, arranged so that when they are dangling allow the rope to move through unhindered, but when angled above the horizontal (in a fall) misalign so they end up in a z shape. I think for that to work, the dogbones would have to be linked somehow so they can't slide around and line up.

build a ground anchor

Late to the party… Fat spongy ropes add friction to the entire system. Maybe you should just buy the OHM and let us know what you think- new gear is cool.