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Posted

Alpine Spam # 7

December 15th 2002

 

How to build an Abalakov

(without your back country abortion kit)

 

 

This is a trick that I find myself doing more and more as I tend to forget to bring all the bells and whistles. At one point in time I never went anywhere without my bent up clothes hanger wire, of course I was stealing cars full time then and it seemed only prudent to be prepared should opportunity come knocking. These days I am much less likely to be caring anything specific for retrieving Abalakov ( ul bee bac en off ) threads. This is especially true in the summer alpine environment.

This technique really doesn’t require any special skill. I am not going to provide a whole micro detail plan here. As I see it there is only one way that this can be done with the equipment I am allowing.

 

Materials needed: One Sewn sling (spectra or whatever) 1 meter or more of 7mm perlon cord.

 

 

Drill Abalakov so that you get a near perfect intersection. Over drill the second hole so that the core is at least 2 or 3 cm’s past the intersection.

Fold sewn sling in two.

Push the loop down one hole stop when the tip of the loop just gets past the intersection. Be sure that your sling is facing the right way. It is possible to turn it slightly once you have inserted sewn sling.

Take 7mm perlon and push it down the second hole so that it not only intersects the sewn sling but goes beyond into the over drilled part.

Tug slightly on the sewn sling (like you have a fish nibbling on a bait hook) Be sure to feed a little extra 7 mil into the second core to reduce resistance.

Pull on the sewn sling “like you were pulling a skier off your sister” The end of the 7 mil should come flying out.

 

This is not near so bad as it sounds as far as finicky fishing goes. I have only done this with sewn sling and Perlon. It may be possible to do this with different material.

 

Mckay-system.jpgThailand Rock

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Posted

nice. perfection in minimalism.

here's a variation on the theme, which i've used twice. it's quite useful in the mtns, where you might have rock gear and maybe not "the hook":

back the head down off a wired nut and use the resulting loop of wire to retrieve the cord. works best if u give the wire a half-twist to "bind" the end of the cord before extracting.

advantage is that it's far easier to insert into the hole than the doubled-sling.

cheers, don

Posted

truth be known is that I got the idea from Joe "Fuckin" Josephson. It was one of the two times we may have climbed together when he twisted up a piece of #6 mechanics wire and did that with the end of the wire. (The same principal works with a sling I thought)Now I actually carry a piece of #6 wire covered with duck tape near the top of most my tools. It is always there. If people ask what the duct tape is for I tell them it is to hold the head of the on. After all I am CANADIAN!

 

Mckay-system.jpg

Posted

Hey thanks for the ideas. I tried "grabbing" my cord with the teeth on an ice screw...didn't work at all! Wish I had had the ingenuity/experience/advice to try the above recommendations on the Kautz last July.

Posted

Will Gadd mentions the same trick in his book. From my experience it requires more accurate hole drilling (you want near perfect intersection), whereas with a hook, you can salvage holes that barely graze each other.

Posted

Joe, Don,

 

Both methods are good ideas. Thanks. They sure beat stuffing hopeful looking twigs into my pockets on the way to synchro.

 

One more V-thread thing: If you encounter an old thread sticking out of ice that has thickened a great deal since the thread was made (can't see the holes), make VERY sure you're rapping on the primary loop and not off a big tail where the free end has also frozen into the ice.

 

If making threads, don't leave big tails.

 

The above sounds unlikely, but it has happened with sad consequences.

 

GB

Posted

Side question - exactly how strong are these things anyhow? I realise part of the answer is "depends on the ice", but they just don't seem strong to me. I know these are used frequently and when no other alternative exists, but they seem pretty dicey to me.

 

What the minimum you would rely on for your rap... 1, 2, 3, or ???

And, these aren't built as protection, but mostly just to rap, correct? Nobody is building a belay station solely out of these, are they?

Posted
Side question - exactly how strong are these things anyhow? I realise part of the answer is "depends on the ice", but they just don't seem strong to me. I know these are used frequently and when no other alternative exists, but they seem pretty dicey to me.

 

What the minimum you would rely on for your rap... 1, 2, 3, or ???

And, these aren't built as protection, but mostly just to rap, correct? Nobody is building a belay station solely out of these, are they?

They are stronger than ice screws and could be used for that and/or belays. The reason they aren't is simply that they take a bit longer to create. If I am down to one screw and I want to build a belay, you can be sure I'm putting in a V-Thread.
Posted

KM,

The Abalokov sandwich (aka: V-thread) is [almost] exclusively used in rap/bail applications. In my experience (which is BY NO MEANS exhaustive), one V-thread of 5 or 6 mm perlon is the preferred cordage diameter and number of anchor points. It is more than adequate for static loading of the magnitude applied by gear-laden ice climbers. The newer the cord the better, because newer cords are stiffer, which helps in the stuffing of the cord into the hole. Older, "fuzzy" kerns make it harder to stuff the cord into the hole and retrieve it, because the stray fuzzies grip the surface of the bore, especially if it's really cold out. Slicker is better. smirk.gif

Posted

In pull tests in perfect ice, the cord breaks before the ice, either at the knot or at the vertex of the V.

 

It's good to carry a 22 cm screw for a V-thread. A 22-cm V will be stronger than a 17-cm V.

 

After you thread the cord through, saw the cord back and forth a little bit to smooth out the vertex of the V.

 

5mm perlon is plenty sufficient for rap anchors, but I'd prefer to have at least 6mm for a piece of a belay anchor.

Posted
After you thread the cord through, saw the cord back and forth a little bit to smooth out the vertex of the V.

 

 

Ice melts under pressure you dope. A sharp angle in the ice isn't going to cut your rope.

Posted
After you thread the cord through, saw the cord back and forth a little bit to smooth out the vertex of the V.

 

 

Ice melts under pressure you dope. A sharp angle in the ice isn't going to cut your rope.

 

rolleyes.gif I disagree. Ice isn't going to melt due to pressure in the time it takes to catch a fall. That said, I don't think the "V" point on a V-thread is likely to cut cord, especially under the low forces of a rappel, and probably not even while holding a leader fall. Sharp ice edges are brittle and will break; I think that is the more important consideration than melting in the few msec it takes for a fall force to be applied to the ice.

 

Sharp ice edges are a good thing to avoid with ropes. I wouldn't want to jug a rope running over a sharp edge of hard glacial ice for example.

 

When I'm rapping from a V-thread, I back up the rappel with an unweighted screw or two for all of the climbers but the last and then clean them when the last person raps.

 

Supposedly V-threads are stronger if you let them air out a bit (refreeze) after you drill them. AlpineDave told me that one. thumbs_up.gif

Posted

Fine, Dru, go sit on an icicle.

 

It takes about five seconds to rub the sling back and forth. The guy who told me about this has been climbing for 20+ years and posts on this site; he is well-versed in rescue systems. Sadly I couldn't find a written report in five minutes to verify my statement.

 

Also, it goes without saying to back it up with a screw and have the last person (lightest) clean it.

Posted

Try, just try, to cut anything with ice. There is more chance of your cord cutting through the ice than there is of ice cutting through your cord.

Posted

thoe are technically puncture wounds... you can get them from bb pellets too

 

you "round off" guys are wasting your time, as a few seconds of experimentation will demonstrate

Posted

That picture shows the holes a little to close together.

 

To get the maximum amount of ice in the "V" portion of the V-thread the 2 screw holes need to be approximately 1.5 times the length of the screw used apart.

Use a 22cm screw to drill, holes should be 30cm apart.

 

Of course, if you believe the ice is better deeper, put the holes closer together. As always, depends on conditions.

 

chris

Posted

I actually think I side with Dru on this one...I realy can't imagine even a very sharp ice edge being capable of resisting deformation enough to cut through a rope. If a few seconds of pulling makes you feel better though, i certainly think that is reason enough.

 

v-threads are one small reason why I like ice climbing in forested settings more - i like the feeling of rapping down on a nice pine much more. smile.gif

Posted
I actually think I side with Dru on this one...I realy can't imagine even a very sharp ice edge being capable of resisting deformation enough to cut through a rope. If a few seconds of pulling makes you feel better though, i certainly think that is reason enough.

 

v-threads are one small reason why I like ice climbing in forested settings more - i like the feeling of rapping down on a nice pine much more. smile.gif

You guys have it all wrong. The reason for smoothing out the sharp point at the back of the V is not to prevent the cord from being cut. The reason is to prevent point loading on the ice which could start a fracture. Fractures, once begun have a way of propagating onward from the point of origin. The idea is to avoid this in the first place.
Posted

Thank you for your valuable contribution CBS. NOw go back to discussing something you might have a clue about boxing_smiley.gif It is easier to fracture a flat surface than a round surface and a round surface is easier than a pointed surface - basic mechanics. Try it sometime with an icicle!

Posted
Thank you for your valuable contribution CBS. NOw go back to discussing something you might have a clue about boxing_smiley.gif It is easier to fracture a flat surface than a round surface and a round surface is easier than a pointed surface - basic mechanics. Try it sometime with an icicle!
That may be true, however, a loop of cord applies less force to a flat surface than it does to a pointed one. Your knowledge of physics appears to be rule based, Dru.
Posted

My knowledge is empirical while yours is theoretical. Or hypothetical. Or even fanciful. Geek_em8.gif

 

try it sometime. It's easier to get a flat sheet of ice to fracture than it is a rounded piece with a diameter equal to the width of the flat piece.

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