Chewbacca wrote:What's stopping the sling from pulling the loop through the hole? There's bound to be a bit of friction and no Abalakovs last forever. Depedning on the diameter of the rope, at some point the loop will get pulled through or at least pulled into the hole and then everything is stuck.

nattfodd wrote:Since the sling is going to pull the rope in the V-thread entrance as hard as it can, and since this is on ice, I would be quite worried that the connection between rope and sling freezes and that it becomes impossible to pull hard enough to separate them (especially if the biner acts as a redirect of the pull direction). And that would mean a stuck rope, which is a problem much bigger than losing a piece of perlon cord.

Those are one of the first things that came to mind. Using a loose strand of rope to block a sling, sketchy. Then, even without ice involved, I cannot imagine the loop of rope easily sliding through the end of the tightened sling; I'd assume it would get stuck completely once the end of the rope loop cinches tight into the sling loop. Anyone happen to know if this has been tried out?

//edit:

as wrote:ingeneous but totally unnecessary, you don't need a carabiner to rappel on an abalakov, only a short piece of cord to make a loop through the abalakov, or if you dont want to waste the cordelette, just run the main rope through the holes.

I'm with Darwin on this one

I have absolutely zero ice expeience, but damn that looks sketchy I wouldn't trust it to hold the weight and I don't think it would be that easy to retrieve.

kiwiw wrote:you pull the rope, as you pull, that loop threaded through the sling pulls through, the sewn sling slides through the abaklov, and it all comes down, only the hole in the ice remains.
understand?

Maybe, but in a typical retrieval setup you'd attach the rope to the left side of the sling (in this case) so the weight of the rope pulls the webbing through the anchor. In this instance you would only have the weight of the biner which might not be enough.

This brings me back to the old "whether or not we could versus whether or not we should?". Why would anyone want to risk their life to retrieve a cheap piece of webbing or cord?

In fact you can't pull the rope down without pulling the bight out of the sling. The only way to do that is by pulling the left strand. (Pull the right strand and the knot will probably get stuck on the 'biner.) You pull a couple of feet on the left strand, then once the bight comes out the whole thing should fall due to the weight of the rope. If for some reason it doesn't (e.g., the sling has cut into the ice and gotten stuck), you can indeed pull on both strands, assuming you were a couple feet above the end of the rope when you started pulling (i.e. you can still reach the right strand).

Unfortunately, while you're pulling the left strand, the weight of the other (right) half of the rope would still be resting on the 'biner. This puts tension on the sling, pulling the rope bight into the hole and creating extra friction resisting your effort to pull the bight out. Might still work with a good sharp pull with body weight behind it.

There's always the previously-mentioned risk that the bight might get deeply jammed into the hole (e.g., while the system is weighted for rappel), making it impossible to pull the bight out. So there's a risk you'll lose your rope in an effort to save a sling. (edit: there's the opposite risk too, that the bight comes out from its own weight while you're standing on a ledge partway down the rappel (removing both your own weight and most of the rope's weight from the anchor). So you're also risking your life to save a sling. What does it say about me that I thought of my rope first?)

Good wrap up nartreb. Bottom line, stop experimenting and stick to the books

Sorry I understand exactly how it works, I was just wondering about safety. Safety should always be a number one concern. I was looking at ways to retrieve gear not because the $5 sling is worth the risk but to look at ways to leave routes looking clean and fresh, practicing leave no trace. Is there another way to rap down without having to feed your rope through the v-thread, that is clean

My first paragraph was directed primarily to Brad's comment and the reply just below it. My second paragraph addressed risks (i.e., safety), but it was largely redundant with previous replies.

Looking at a photograph can't tell us how reliable this system is in the real world. Whether it fails will probably depend on lots of factors (temperature, wetness, ice conditions, rope size, sling width, rope flexibility, rope sheath material, sling material), some of which will vary from one day to the next. That in itself is enough to dissuade me from using this system (absent some rigorous study of what its limits really are).

As for alternatives, consider this if you've got a good tree handy:
http://www.summitpost.org/article/17223 ... nchor.html

(edit: but be careful. In winter you may not be able to tell whether the tree is solidly rooted.)

Re tree or similar available: google for macrame anchor.

//edit: this is just FYI, don't use it unless you know 100% what you're doing!

nartreb wrote:My first paragraph was directed primarily to Brad's comment and the reply just below it. My second paragraph addressed risks (i.e., safety), but it was largely redundant with previous replies.

Looking at a photograph can't tell us how reliable this system is in the real world. Whether it fails will probably depend on lots of factors (temperature, wetness, ice conditions, rope size, sling width, rope flexibility, rope sheath material, sling material), some of which will vary from one day to the next. That in itself is enough to dissuade me from using this system (absent some rigorous study of what its limits really are).

As for alternatives, consider this if you've got a good tree handy:
http://www.summitpost.org/article/17223 ... nchor.html

Doing rappels is the most dangerous thing you can do while climbing. I have had a friend DIE using the set up in that linked page.

Think about that.

Guyzo wrote:

nartreb wrote:My first paragraph was directed primarily to Brad's comment and the reply just below it. My second paragraph addressed risks (i.e., safety), but it was largely redundant with previous replies.

Looking at a photograph can't tell us how reliable this system is in the real world. Whether it fails will probably depend on lots of factors (temperature, wetness, ice conditions, rope size, sling width, rope flexibility, rope sheath material, sling material), some of which will vary from one day to the next. That in itself is enough to dissuade me from using this system (absent some rigorous study of what its limits really are).

As for alternatives, consider this if you've got a good tree handy:
http://www.summitpost.org/article/17223 ... nchor.html

Doing rappels is the most dangerous thing you can do while climbing. I have had a friend DIE using the set up in that linked page.

Think about that.

Sorry to hear about your friend. How did the anchor fail?

norco17 wrote:

Guyzo wrote:

nartreb wrote:As for alternatives, consider this if you've got a good tree handy:
http://www.summitpost.org/article/17223 ... nchor.html

Doing rappels is the most dangerous thing you can do while climbing. I have had a friend DIE using the set up in that linked page.

Think about that.

Sorry to hear about your friend. How did the anchor fail?

Same question here.

Unlike some other retrievable-anchor methods, the one in the link can't just fail if something pulls a bit wrong, this way or that. Something else must have happened that didn't involve correct use of the method or was independent of the method.

Agreed. It's a good system (for appropriate applications).

V-thread pull testing

http://www.youtube.com/watch?v=VWk_WukoJ9E

3,800 pounds and then the webbing broke. The forces generated during rappel are rarely above 500 pounds. Make of it what you will- I'd certainly feel more comfortable with a backup, like a second v-thread, but generating 3,800 pounds of force on rappel is virtually impossible. (Guyzo, feel free to correct me if I am wrong.)

-Mark

Mark Straub wrote:V-thread pull testing

http://www.youtube.com/watch?v=VWk_WukoJ9E

3,800 pounds and then the webbing broke. The forces generated during rappel are rarely above 500 pounds. Make of it what you will- I'd certainly feel more comfortable with a backup, like a second v-thread, but generating 3,800 pounds of force on rappel is virtually impossible. (Guyzo, feel free to correct me if I am wrong.)

-Mark

Cool test. It's labeled "#1," so are there others?

I have no ice-anchor experience, but if the elitists on this site think that means I'm not entitled to comment on something regarding common sense and a knowledge of materials, physics, and such, they can blow it out their ass!

Agreed regarding the impossibility of 3800 pounds. My concern would be the variability of ice and a possible unseen flaw that would considerably weaken the anchor. And drilling the v-thread just a bit smaller would have a substantial impact on the size of the ice encircled by the webbing. But obviously if it's done right, it's plenty strong.

norco17 wrote:

Guyzo wrote:

nartreb wrote:My first paragraph was directed primarily to Brad's comment and the reply just below it. My second paragraph addressed risks (i.e., safety), but it was largely redundant with previous replies.

Looking at a photograph can't tell us how reliable this system is in the real world. Whether it fails will probably depend on lots of factors (temperature, wetness, ice conditions, rope size, sling width, rope flexibility, rope sheath material, sling material), some of which will vary from one day to the next. That in itself is enough to dissuade me from using this system (absent some rigorous study of what its limits really are).

As for alternatives, consider this if you've got a good tree handy:
http://www.summitpost.org/article/17223 ... nchor.html

Doing rappels is the most dangerous thing you can do while climbing. I have had a friend DIE using the set up in that linked page.

Think about that.

Sorry to hear about your friend. How did the anchor fail?

His name was Randy Grandstaff, he was a guide at RR, some of you folks may have used him..........

Randy was guiding, the client couldn't do the pitch so he lowered her to the ground. Didn't wish to leave ugly sling.........

Accidentally clipped the "pull rope" into the devise along with one descent rope......It pulled when he weighted it. ........

Learn from mistakes.