Just wondering what ideas people have for a good belay anchor?

I typically go for 2-3 screws, rigged with the rope or cord.

I also try and incorporate a tool into the anchor. They help.

good points Brett. In my recent curiousity regarding the strength of Ice Threads (i.e. Abalakov, V-thread) I came across this experiment conducted by Petzl via video

Petzl video Ice threads vs Screws

best wishes for a safe season to everyone

Here's one I made yesterday. I used three screws, two 10cm and one 13cm (the ice was thin) staggered, two above one another, and one off to the side...it held!

Ice anchor off three screws. Submitted By: J. Fox on Nov 17, 2008

Is the Nalgene bottle mandatory?

I will usually place one screw vertically above another but staggered to the side and sometimes if I think the ice isn't that great I'll drill four 16cm holes in the ice and use a cordelette as an equalizer and back that up with a long screw. I also hang a Nalgene container but it's usually filled with Scotch; just in case!!!

Mike,

Let's do Deep Freeze. I hear it's in HUGE!!

sorry jack.
I already stole mike from ya for another project of mine.
Youll have to wait for this big stud :) :)
or. you can just jump in the element and meet us in moab!!!!

Excellent Video..

Thanks for putting that up.

Thanks for posting the vid Kirra, That was interesting.

Makes me wonder if you guys/gals back up your V-Threads when rapping? In bomber ice, I usually back it up with one screw (almost equalized, but has just a smidge of slack) as the heaviest person goes down first, then the screw is removed by the last person to rap. In theory, if the heaviest person didn't pull on the screw, the lightest person (always me) won't blow the anchor. The only problem with this is that the last person is rapping with absolutely no back up.
If the ice is poor, I will make a total of 2-3 V-Threads and equalize all of them.

Any thoughts? Suggestions?

hi Micah yeah I have the same question about installing/removing the icescrew backup, perhaps better to rap 1st ~(:

but you'd be forfeiting that nalgene also

On raps, I will make the v-thread and put an ice screw in as a backup, but make sure it is far enough away in case the ice fractures.

The first person to rap bounce tests the hell of the anchor (maybe with two screws as a backup if you are really worried). It is up the last person to rap if they feel comfortable pulling the backup. If not, no questions are asked.

For end of pitch anchors, I usually use two screws staggered vertically, slightly offset, and equalized with a double length sling. I'll add in pieces as I feel necessary. I've made multiple v-threads AND used a few screws in an anchor before, it just depends on what you need to make it bomber.

I have to agree with most on here with one screw on top of the other with a little bit of a stagger. I'll use 3 screws if I am not 100% positive of the ice. I have also been known to use a clump of bushes for an anchor. You gotta love obscure San Juan climbs.

As to the v- thread I always make the heaviest guys go down first with a backup screw. If the ice is not great I will make two v-threads and equalize them.

Notes on threads:

Anyone incorporate a v-thread solely as the belay, and/or use a-threads, more than not just go for screws, or mix it up between types? (assume rock & trees aren't there)

-- as long as I see good ice off the anchor for the Jesus screw, I usually just go for a quick 2 screw set for the main anchor.


With rapping, the back-up screw -- horizontally above, at, or below the thread?

As for the v-thread as an anchor by itself no. If I have a screw for a v-thread I will use that as well. I have been short on screws and used a v-thread as my secondary point. In fact I did two v-threads and then used the screw.

When backing up the v-thread I always put the screw above the v-thread. When building the rap I will make the v-thread below my lowest screw. I then will run the cord through the v-thread and tie it off. I then take an alpine draw and clip it to the best screw above the v-thread and take it down to the cord and tie it off equal with a carabiner equal to the cord through the v-thread. This way if the v-thread blows the top screw does not get shock loaded.

It would have been nice if they had given numbers on the pull tests in that video. I can yank a fat bolt out of granite with enough force. That doesn't make it unsafe.
I've been rapping off single v threads (in good ice) since the early eighties. Never gave it a second thought. Of course back then we weren't clipping bolts every 8 feet either.
Come to think of it didn't we used to rap off a single bollard (cut out of snow) when necessary.

I wonder if webbing would have broken the ice at the same lb as the cord? Poss. more surface area would give it a little better chance? Or how about testing 8.8mm ropes? I've seen some people make just the holes and feed the rap rope straight in to the hole, rap, then pull ropes and leave no tat behind in the ice.

Ah yes, threw that Jesus-screw term out there. Based on the Long's rock definition. The Jesus screw would be the first screw placed off the anchor. My learning was to place that good screw to protect the anchor when going off on the lead; after that, whatever I wanted/needed to do to keep from falling & climb under control in a fluid motion.

As well, the exit-screw placed before switching terrain types.

Yeah Mark thanks for the info and Kirra for the video feed. I was also curious about a v-thread in a vertical position rather than a horizontal one. Also in the video it didn't look like they made the v-threads very deep. In peoples experience or is there stats about v-threads of varying depths, such as using a 16cm screw compared to a 22cm screw. I would think a longer screw (deeper hole, more ice that needs to be displaced in case of failure, also placing screws farther apart) would produce a stronger v-thread. Any thoughts or numbers out there? Have a day.

Juan

Juan:

here's their site with download papers near the bottom -- under Research:
www.strikerescue.com/downloads/

Ice Climbing Anchor Strength, I believe is their latest ITRS presentation. There are a couple of angles that give optimal results.


(ps -- don't thank me; I'm not the guru -- but it sure does help to incorporate actual results with climbing styles when considering anchors)