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hrtmnstrfr
Jan 15, 2007, 7:16 PM
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I am a photographer who has decided to venture off the ground and start shooting free climbers via ascending a rope. I have a petzl ascender and a gri-gri and I know how to set up my fixed line in most cases but there is one place I want to photograph that does not allow anchoring to trees. However, the park service has bolted anchors at the top of the routes and there is trail to provide access to the anchors. My question is, how do I set up my fixed rope off two anchors (bolts & hanger)? My first thought was to just use two quickdraws and tie a figure eight knot and hook that knot through both quickdraws (which are attached to the anchors), however, I have no idea if that would be safe. Can anyone help me?
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atpeaceinbozeman
Jan 15, 2007, 7:22 PM
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Sounds pretty good, maybe use a locker....
Have fun, be safe.
If you want to go further, if possible, anchor the bottom of the line from a tree or boulder away from the cliff face. This can pull you out from the wall a bit.
Cheers,
Tom
EDIT:
just remebered you can't use trees...oh well...
(This post was edited by atpeaceinbozeman on Jan 15, 2007, 7:23 PM)
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cchildre
Jan 15, 2007, 7:54 PM
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The ideal setup would be to tie a double loop figure eight known often as an eight with "bunny ears" and then clip each ear into each bolt with a locker.
http://www.animatedknots.com/fig8loopdoublerescue/index.php
Standard know for this setup for most of the worlds cavers. a Triple loop figure eight is also possible.
Using the rope alone in this system eliminates the quickdraws as potential failure points. Lockers are always best though you could use the standard gates, just know it lowers the level of safety achieved.
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hrtmnstrfr
Jan 15, 2007, 7:57 PM
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Thanks,
So do you mean one loop through each locker or both lockers through both loops?
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chh
Jan 15, 2007, 8:00 PM
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Try using a double loop knot, such as a bowline or a figure 8. Attach each of the two loops to the bolt hangers via a locking carabiner. Adjust the size of the loops accordingly.
1 knot, 2 biners. Simple and bomber.
edit - someone beat me to it. the webbing is a good idea as well if you have edge issues. You could also pad the edge with something.
(This post was edited by chh on Jan 15, 2007, 8:05 PM)
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stickyfingerz
Jan 15, 2007, 8:01 PM
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Depending on how close the bolts are to the edge, you might want to bring some longer pieces of webbing or a cordalette. That way you can extend your anchor point so that your rope isn't sawing away on the edge. Think TR anchor setup and you should be good to go.
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cchildre
Jan 15, 2007, 8:22 PM
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The two loops should go to different bolts. You can adjust the length pretty easily to balance the setup if the bolts are staggered. Practice the knot before taking it to the field (redundant I know) because I have seen very experienced cavers struggle over the knot for an hour having forgotten how to tie it.
If you looped through both lockers with both loops, if one of the bolts failed then your anchor extends and impacts the remaing bolt with considerable force and possibly cause total failure. You really want to split the force between the two anchors.
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hrtmnstrfr
Jan 15, 2007, 8:24 PM
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Got it, thanks a lot.
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