SummitPost.org

Hey Guyzo,

I just did the Great Red Book in RR and saw the initials at the 1st belay station bolts. I was curious so I did a little Googling and found out the story on Mountain Project. I'm still not 100% clear on how it happened. There's still speculations regarding that incident. The illustration from Scott on SP, however, is clear to me.

There are now two bolts at the very top of the 2nd pitch along with some webbing but no rap rings. I wonder if these bolts were there at the time.

I've popped a V-thread, it's not that hard: just set it in crappy columnar ice on a warm day and drop your body weight onto it from above (harness clipped directly to anchor, no dynamic rope in system: near-factor-2 fall of a maybe four feet). A breadloaf-sized chunk of ice popped loose. Of course I did this intentionally and fell only a few inches further before landing on my feet. (Got a nice bruise from the ice chunk hitting me on its way down though.) Even in that crappy ice it probably would have been fine for a rappel, but this highlights the usefulness of a backup anchor while preparing to rappel, if possible (as does Guyzo's story).

This video from Petzl is less than ideal because it gives no numbers, but it shows V-threads failing.

In particular, it shows that the failure mode described by nartreb is a common one.

I thought the all topic was about the specific set up of the pictures not abalov in general.
Abalow if set in solid ice are very solid, as you can see from the video posted earlier the webbing breaks first.
If the ice is questionable you can create two abalovs and equalize them
I used abalov on several occasion for rappel and even a couple of times for belay, and all the climbers I know who climb alpine or multi pitch, use them with confidence...

Here's another v-thread testing video, with 5 guys on a 3:1 pulley system unable to pull out the v-thread until it is stripped down.

http://www.youtube.com/watch?v=ioGaWOZ2 ... re=related

climbxclimb wrote:I thought the all topic was about the specific set up of the pictures not abalov in general.

Yes, there's been a little drift.

climbxclimb wrote:Abalow if set in solid ice are very solid, as you can see from the video posted earlier the webbing breaks first.

Yes, Abalakovs are very strong in good ice. I'm still interested in how strong they are and what affects their strength. Here's a link to the most complete treatment of the subject I've seen so far. It covers more than just strength of Abalakovs.

Mark Straub wrote:Here's another v-thread testing video, with 5 guys on a 3:1 pulley system unable to pull out the v-thread until it is stripped down.

Mark, the problem with that video is that it's difficult to tell how much force those five guys managed to apply to the anchor. I doubt it was much larger than 3 kN.