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Post by gregggagliardi on Feb 28, 2013 18:20:17 GMT -8
What is the safest way to belay a lead climber on snow? You will look long and hard to find it. The best discussion that I have found is in Craig Connally's book (The Mountaineering Handbook, 2005, Blacklick Ohio: McGraw-Hill, pp 169-170). The principle that Connally advances is the same one that John Long advances in his most recent book on anchors; the first piece of pro placed is the most important (the so called "Jesus nut"). For Connally the first piece of pro is the usual belay anchor. He advocates setting up the belayer on a less substantial anchor below the main anchor. The reason: a factor 2 fall on the belayer is now impossible unless the main belay anchor above the belayer fails. If the belayer is 10 feet below the main anchor and the leader falls 10 feet beyond the anchor the worst fall is a 10/20 = .5 factor fall. in snow (and ice) it is especially important to limit forces on the pro.
Gregg
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Post by nicklyle on Mar 7, 2013 1:32:09 GMT -8
Good. I would like to experiment with these ideas somewhere with a good runout.
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Post by gregggagliardi on Mar 7, 2013 11:43:09 GMT -8
Take a look at the diagrams in Connally's book (pages listed above). The technique is basically a variation on one that guides have used for years to extend the belay anchor so that they can better see the client (second). It is easy to adapt this basic idea for teams that swing leads and for teams with one leader and one follower. In the latter case the leader brings the second up on an extended master point and the ties the follower into a simple anchor at that location (could be a piece of rock pro, ice screw or solid picket). The leader then has the belayer but them on belay on to the rope extending to the main belay anchor.S/He unties the MMOH that he used to create the extended master point used to belay the second and then the leader ascends to the main anchor, essentially on top rope. The main anchor essentially becomes the leader's first piece of pro. Once beyond that main anchor no fall that the leader takes onto the main anchor can be any higher than a factor 1 fall.
The pictures in Connally's book make this easier to understand but it isn't presented in enough detail to show how it works in all situations. I have considered making a video of the whole thing to better illustrate how it works in practice. If there is enough interest I could either post it or post a link to it.
Gregg
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Post by nicklyle on Mar 14, 2013 23:46:27 GMT -8
I remember the Jesus nut principal being taught as standard when setting up a belay with ice screws in an intermediate climbing ice-climbing lecture. It makes a lot of sense to make it the standard when belaying on snow anchors as well. As well as preventing a fall straight onto the belayers anchor it makes the direction of pull on the belayer predictable. One issue is the pulley effect increasing the load on that first piece; on the other hand, even if the first piece of snow-pro pulls, it will absorb a good portion of the fall energy in doing so. Placing a screamer on this first "Jesus" piece might be good practice, especially when using a belay device or Munter hitch that has no dynamic element.
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Post by gregggagliardi on Mar 15, 2013 10:05:47 GMT -8
In the best case scenario the main anchor (built by the climber who led this pitch) is a multipiece anchor (rock, snow or ice) and the belayer's anchor, located below the main anchor ( say 10 ft) is smaller one designed only to help the belayer maintain his or her stance, especially when catching a fall. The main anchor is the first piece of protection in the system for the upcoming pitch. Note that as the leader of the next pitch moves from the belayer's anchor to the main anchor s/he is on top rope to that anchor. Once past that anchor any fall will be no greater than a factor 1 fall; in fact, if the leader places another piece of pro soon after passing the main anchor (a good practice) this is even more bomber.
The key to safety is insuring that the main anchor is bombproof. If set up properly it should never have to hold more than a factor 1 fall. The belayer can still belay off that anchor at a distance below the main anchor by running the rope through the master point and down to the belayer. The belayer next ties a knot on the section of rope going to the climber. This could be a figure 8, alpine butterfly or inline figure 8. For additional system stability, the rope going to the climber can be tied on the rope going to the belayer with a mule knot backed up with an overhand. In either set-up the knot loop serves a new remote master point for belaying the second.
If the follower becomes the new leader, the belayer undoes the mule knot and puts the new leader on a belay off his or her harness. If not, the follower ties into the former belayers anchor, undoes the mule knot and puts the leader on belay. Depending on how the first belayer clipped the main anchor master point, the new leader may need to briefly re-clip to make sure that s/he is not back clipped at the main anchor. If the belayer is aware of this potential problem it can be avoided by initially clipping the main anchor so that it won't be back clipped when the leader arrives at the main anchor.
An even simpler, less gear intensive set up is possible. The belayer lowers from the main anchor on a Munter knot, sets up the belayer's anchor and belays the second off the Munter on the main anchor. Guides sometimes set up at a distance this way in order to have a better view of the second.
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Post by nicklyle on Mar 16, 2013 9:29:44 GMT -8
This is interesting. I am having a bit of trouble visualizing how to escape the belay if you are belaying off a mule knot tied in a pendant stretch of rope below the main anchor. To what anchor do you transfer the load of the fallen climber? It seems like you and the fallen leader would each be tied by Munter-Mules into the same bit of rope. A drawing would help visualize this. I can see how the belayer would detach herself, but I am not sure how available the extra rope would be to continue with a rescue effort in this set-up. I guess I need to try it.
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Post by gregggagliardi on Mar 17, 2013 16:45:04 GMT -8
Nick:
Today I took several pictures showing different stages of one type of set-up on this system. There is not enough room within the attachment limitations to present this in a single reply to your post.
The points that you make are really good ones. They have prompted me to go back and re-evaluate this system. I believe that I now have good answers to your questions in terms of belay escapes, rescues etc.
Here is what I have also learned but cannot present in any simple way:
First, the way this system is best done on snow is a bit different than ice or rock. I will need some pictures on snow to show this.
There are some choices to be made about how you set up the system in terms of speed versus security trade-offs. This will take a video to properly demonstrate
Careful assessment of the climbing situation leads to a number of simple variations on this system. Again, it will take a video to show this.
This system is flexible enough to accommodate pretty much any situation. Good news. I can do anything with it that i can do directly off the main anchor.
It is frustrating trying to present this information in a narrative format. This stuff is much easier to present in a video format. Even sequential photos really leave a lot unsaid.
Gene or Jim: If you read this, my question is how do we get this blog set-up so that we can present more detailed info in terms of photos, videos etc. They say a picture is worth a thousand words. Well a video is worth at least thousand pictures.
I am considering making video on this stuff but how do I get the video to this group??
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Post by nicklyle on Mar 24, 2013 18:16:08 GMT -8
Drop box is a great way to share larger files. In the avalanche class we share documents using a google docs site. This allows everyone access anytime to a set of documents that sit in the cloud.
Even better would be if we could go climb some steep snow together; you could really show me the system then. We could film it at the same time.
Nick
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Post by geneyore on Mar 29, 2013 5:24:47 GMT -8
I definitely need video help here.
Let me figure out how we best share large pic &video files.
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