Half Ropes and Run Outs?

[wfinley]

I have a question about half ropes that vexes me: I always climb on two 8.5 mm half ropes. One meandering routes I will often only clip one rope for say, half the pitch, and on the second half I'll clip the other rope to minimize drag.

 

If I take a fall onto one of the 1/2 ropes but the other rope was last clipped in, say, 40-50' below me, is this considered bad? If you climb on 1/2 ropes do you run it out like this or do you use long slings to minimize drag and alternately clip each rope as you climb.

 

Obviously if the fall potential includes sharp rocks / edges one would alternately clip ropes in case of a core shot - but what about on routes where this isn't an issue?

 

PS - According to Mammut's website: "When used singly, half ropes are tested with 55 kg fall weight and must resist 5 standard falls, with a diameter of 8–9 mm and 42–55 g per metre. Used singly, they are suitable for additional securing, for example if there are two other climbers on the rope." However - Black Diamond's 8.1 Half Rope has "No" marked for "Resistance to a factor 1.77 fall over an edge at radius 0.75mm" whereas their 9 has "Yes" marked.

 

 

[powderhound]

It has been my understanding that unless your protection is bomber you only want to clip one rope into the protection. If you clip both ropes the impact force is higher and therefore more likley to pull the protection. I use double ropes on ice and I climb with them both ways that you described, on meandering routeds I use one for the first half and the other for the next to reduce rope drag. On straight forward routes I just clip which ever one I grab first.

[stinkyclimber]

See the Dec. 4 posting on Will Gadd's blog for a debunking of a number of half-rope myths and general discussion on when and why to use halfies. http://gravsports.blogspot.com/

[wfinley]

Hey - thank for that link. Gadd's blog linked to this thread which has decent info:

http://www.rockclimbing.com/cgi-bin/forum/gforum.cgi?post=1394069;sb=post_latest_reply;so=ASC;forum_view=forum_view_collapsed;guest=829849

[catbirdseat]

In answer to your original question, if you are using half ropes you should clip alternately for greatest redundancy, UNLESS you have a good reason to do otherwise. If the route wanders way left and then right again, that would be a good reason to clip only the "red" rope initially, and then the "green" further up the pitch.

[TrogdortheBurninator]

If you dont have redundancy, you are treating your half rope as a single rope. You need to evaluate the difficulty of the terrain, nature of the fall, etc in determining if this is the proper decision. The half ropes arent designed to be used this way, but supposedly most current half ropes can survive one hard fall (1.77 FF with 80kg). I would prefer a bigger factor of safety than that. I usually try to add some redundancy with my clips when possible. i.e. if a route wanders hard left, and would place a 90 degree dog leg in a single rope, I would ideally like to still have the rope I will be cliping after the traverse protecting me from a catastrophic ground fall. A good example route is princely ambitions: Assuming red and green ropes, alternate red and green ropes for ~50 ft. Clip only red tope for next 20 ft. Traverse hard left. Clip Green Rope for next 20 feet. Begin alternating again. Keeping the rope angles small, I dont think you will experience much more drag than if you just alternated half the route on each rope.

[scrambled_legs]

A number of questions were answered in this thread:

 

http://www.cascadeclimbers.com/forum/ubbthreads.php/ubb/showflat/Number/537507/page/0/fpart/1