Forums: Climbing Disciplines: Trad Climbing:
Belay methods on a marginal anchor?
RSS FeedRSS Feeds for Trad Climbing

Premier Sponsor:

 
First page Previous page 1 2 Next page Last page  View All


toejam


May 1, 2006, 2:41 PM
Post #1 of 28 (3208 views)
Shortcut

Registered: Sep 24, 2002
Posts: 358

Belay methods on a marginal anchor?
Report this Post
Average: avg_1 avg_2 avg_3 avg_4 avg_5 (0 ratings)  
Can't Post

Math guys help me out here, please.

Assume for the sake of discussion that one is forced to rely on a questionable anchor for the purposes of:

a. lowering one or more injured victims.
b. belaying a leader.
c. belaying a follower

To minimize the force on the anchor, the ideal belay method for a would be to attach the belay device to the anchor itself. For b and c, it might be to belay off of the harness for a little extra force absorption, though the increase in fall factor would offset this in situation b. In any case a redirected belay through the anchor would increase the forces unnecessarily due to force multiplication/pulley effect. Right?

Assuming the belayer is attached to the anchor but partially supporting his own weight (say 40%), how does this play into the decision. Anyone have some equations to help sort out my muddled thinking on this?

Thanks.


clmbnski


May 1, 2006, 3:58 PM
Post #2 of 28 (3208 views)
Shortcut

Registered: Feb 10, 2002
Posts: 85

Re: Belay methods on a marginal anchor? [In reply to]
Report this Post
Average: avg_1 avg_2 avg_3 avg_4 avg_5 (0 ratings)  
Can't Post

I think I would belay off my harness in all situations where the anchor is questionable. Try to find a good stance where your body is in a position for the most power. Then the anchor is just a backup. I would not redirect the belay through the anchor because as you said "the pulley effect"

With the redirect:
The anchor takes 1.6 times a lower factor fall (not that much lower) compared to a factor two load. According to my calculations, 1.6 times the impact force of any fall factor will be a higher impact force than the factor 2 impact force. So I would never use a redirect through the anchor.

Can someone confirm that?

I used this equation for impact force http://www.bealplanet.com/...age=force_choc〈=us

Chris

edited to clarify


catbird_seat


May 1, 2006, 4:12 PM
Post #3 of 28 (3208 views)
Shortcut

Registered: Apr 7, 2004
Posts: 425

Re: Belay methods on a marginal anchor? [In reply to]
Report this Post
Average: avg_1 avg_2 avg_3 avg_4 avg_5 (0 ratings)  
Can't Post

I agree completely with clmbnski. Belay off your harness, get a good stance, and pray to whichever god you believe in.


gunkiemike


May 1, 2006, 5:35 PM
Post #4 of 28 (3208 views)
Shortcut

Registered: Oct 1, 2002
Posts: 2266

Re: Belay methods on a marginal anchor? [In reply to]
Report this Post
Average: avg_1 avg_2 avg_3 avg_4 avg_5 (0 ratings)  
Can't Post

In reply to:
I agree completely with clmbnski. Belay off your harness, get a good stance, and pray to whichever god you believe in.

Agreed. I'll also add - tell your partner not to fall. Be honest so they can make an informed decision; it's their life at risk too.

And by all means consider NOT continuing. Downclimb to the last good gear and abandon the attempt or belay from there.


jimdavis


May 1, 2006, 10:22 PM
Post #5 of 28 (3208 views)
Shortcut

Registered: May 1, 2003
Posts: 1935

Re: Belay methods on a marginal anchor? [In reply to]
Report this Post
Average: avg_1 avg_2 avg_3 avg_4 avg_5 (0 ratings)  
Can't Post

In reply to:
I think I would belay off my harness in all situations where the anchor is questionable. Try to find a good stance where your body is in a position for the most power. Then the anchor is just a backup. I would not redirect the belay through the anchor because as you said "the pulley effect"

With the redirect:
The anchor takes 1.6 times a lower factor fall (not that much lower) compared to a factor two load. According to my calculations, 1.6 times the impact force of any fall factor will be a higher impact force than the factor 2 impact force. So I would never use a redirect through the anchor.

Can someone confirm that?

I used this equation for impact force http://www.bealplanet.com/...age=force_choc〈=us

Chris

edited to clarify

I would! I wouldn't want to catch a factor 2 fall that's pulling straight down on my hips! F*ck that!

Hopefully your only talking about having this happen until the climber get a good piece in (hopefully soon!!!) and by redirecting through the anchor, your minimizing the fall factor, and the amount of time the climber is in free-fall...reducing the force felt on both the belayer and the climber.

Taking into account that the belay should slip at around 2kn...the climber won't feel over 4kn (or less, not doing the exact math here to account for friction) so your force felt on the belay anchor is still under 6kn, in the redirect.

Say you belay straight off your harness. Climber takes a factor 2 fall onto you...rope slams down against your leg/ foot or something...pulls you out of your stance...you now have 2 climbers falling onto the anchor, both in relativly high factor falls (depending on the belayers attachment to the anchor: sling, or rope) so I think that'll end up being around 4kn on the anchor, except with both the belayer and climber getting thrown around.

I'd hope you could build an anchor that'd hold at least 6kn...that shouldn't be TOO hard.

Cheers,
Jim


brutusofwyde


May 2, 2006, 12:47 AM
Post #6 of 28 (3208 views)
Shortcut

Registered: Nov 3, 2002
Posts: 1473

Re: Belay methods on a marginal anchor? [In reply to]
Report this Post
Average: avg_1 avg_2 avg_3 avg_4 avg_5 (0 ratings)  
Can't Post

Personally, I see far too many folks belaying the leader off a questionable anchor, and they never seem to realize it.

I'm talking about an anchor without at least 1-2 pieces placed specifically to oppose upward pull.

Brutus


toejam


May 2, 2006, 1:54 AM
Post #7 of 28 (3208 views)
Shortcut

Registered: Sep 24, 2002
Posts: 358

Re: Belay methods on a marginal anchor? [In reply to]
Report this Post
Average: avg_1 avg_2 avg_3 avg_4 avg_5 (0 ratings)  
Can't Post

In the situation that got me thinking about this, the belayer was forced to rely on a questionable tree in a cliff face of loose rock. He lowered the rescuer who picked a victim off the face and secured him to the rescuer's harness, then lowered together. The belayer had about 60% percent of his weight on the anchor, and the lowering line redirected through the anchor. Only an ATC was available as a device.

What I'm trying to reason out is whether the force multiplication is really an issue in this case. Either way, the weight of the rescuer, victim, and belayer are all on the anchor. I'm not sure that any of this force is multiplied. Naturally the lowering will be a little bumpy, and I suspect that this would be where the force multiplication kicks in, but I'm not sure.

If the belayer did go off of his harness, I'm sure that the ride would have been a little bumpier, resulting in more force on the anchor, and all of his weight would have also been on the anchor. Perhaps the best option would have been a munter on the anchor itself.


dirtineye


May 2, 2006, 2:42 AM
Post #8 of 28 (3208 views)
Shortcut

Registered: Mar 29, 2003
Posts: 5590

Re: Belay methods on a marginal anchor? [In reply to]
Report this Post
Average: avg_1 avg_2 avg_3 avg_4 avg_5 (0 ratings)  
Can't Post

Questionable vegetables turn out to be good in my experience, but you are wise to think about the smoothness of the lower or rappel.


clmbnski


May 2, 2006, 8:42 AM
Post #9 of 28 (3208 views)
Shortcut

Registered: Feb 10, 2002
Posts: 85

Re: Belay methods on a marginal anchor? [In reply to]
Report this Post
Average: avg_1 avg_2 avg_3 avg_4 avg_5 (0 ratings)  
Can't Post

In reply to:
And by all means consider NOT continuing. Downclimb to the last good gear and abandon the attempt or belay from there.
I think that is a good point. Look at all options before commiting to the sketch anchor. Have you thoroughly searched for other possible places to build an anchor. If there is nothing, downclimb (if you can) and rethink things. I have downclimbed over 100ft at least a couple times.

As far as the rescue situation you described:
In reply to:
In the situation that got me thinking about this, the belayer was forced to rely on a questionable tree in a cliff face of loose rock. He lowered the rescuer who picked a victim off the face and secured him to the rescuer's harness, then lowered together. The belayer had about 60% percent of his weight on the anchor, and the lowering line redirected through the anchor. Only an ATC was available as a device.
Did the belay find himself being sucked up into the anchor? I find that belaying a second with a redirect if fine, but lowering them pulls me into the anchor. I think belaying straight off the anchor would have been the best option. Maybe extend the ATC and back it up with a prussik. Munter would work but I think it can twist the rope during lowering (I dont really know how big an issue it would be.)

In reply to:
Say you belay straight off your harness. Climber takes a factor 2 fall onto you...rope slams down against your leg/ foot or something...pulls you out of your stance.
Yeah I guess that could happen, but with the redirect you get launched into the powerpoint (unless you are anchored down somehow) and that could cause you to lose control. But I think we all agree that you should put a piece of pro in asap when you leave the anchor.


dirtineye


May 2, 2006, 10:14 AM
Post #10 of 28 (3208 views)
Shortcut

Registered: Mar 29, 2003
Posts: 5590

Re: Belay methods on a marginal anchor? [In reply to]
Report this Post
Average: avg_1 avg_2 avg_3 avg_4 avg_5 (0 ratings)  
Can't Post

Some of you are seeming to say that the belayer doing a lower off a questionable tree should be attached to the anchor?

IN this particular situation, the belayer should be attached to somethign else besides the ancor, because if the lower pulls the anchor, the belayer is dead as well as the loweree.

Better to have a good stance to one side and then if the anchor goes you can try to hold it or let go god forbid when you have to.

But these days, we don't do no marginal anchors. Can you say, bolt kit?


krusher4


May 2, 2006, 11:30 AM
Post #11 of 28 (3208 views)
Shortcut

Registered: Nov 17, 2005
Posts: 997

Re: Belay methods on a marginal anchor? [In reply to]
Report this Post
Average: avg_1 avg_2 avg_3 avg_4 avg_5 (0 ratings)  
Can't Post

yell down to your second "If you fall we will both die....so ummm....don't"


adnix


May 4, 2006, 1:20 AM
Post #12 of 28 (3208 views)
Shortcut

Registered: May 19, 2003
Posts: 584

Re: Belay methods on a marginal anchor? [In reply to]
Report this Post
Average: avg_1 avg_2 avg_3 avg_4 avg_5 (0 ratings)  
Can't Post

In reply to:
a. lowering one or more injured victims.
b. belaying a leader.
c. belaying a follower
In every case I would belay directly off the anchor. Once the leader get's something somewhat solid in I might switch to body belay. It depends on the anchor: if it can take upward pull I might be too lazy to switch.


catbird_seat


May 4, 2006, 2:32 PM
Post #13 of 28 (3208 views)
Shortcut

Registered: Apr 7, 2004
Posts: 425

Re: Belay methods on a marginal anchor? [In reply to]
Report this Post
Average: avg_1 avg_2 avg_3 avg_4 avg_5 (0 ratings)  
Can't Post

Dude, you have it ass backwards.


adnix


May 5, 2006, 6:10 AM
Post #14 of 28 (3208 views)
Shortcut

Registered: May 19, 2003
Posts: 584

Re: Belay methods on a marginal anchor? [In reply to]
Report this Post
Average: avg_1 avg_2 avg_3 avg_4 avg_5 (0 ratings)  
Can't Post

In reply to:
Dude, you have it ass backwards.
Me? No, I don't.

I can give you a very thorough explanation if I wish. It's pure physics. Weight, pulleys, friction and counterweights. If you belay directly off the anchor, you'll eliminate the counterweight. It's pretty simple really.


adnix


May 5, 2006, 6:18 AM
Post #15 of 28 (3208 views)
Shortcut

Registered: May 19, 2003
Posts: 584

Re: Belay methods on a marginal anchor? [In reply to]
Report this Post
Average: avg_1 avg_2 avg_3 avg_4 avg_5 (0 ratings)  
Can't Post

In reply to:
I think I would belay off my harness in all situations where the anchor is questionable. Try to find a good stance where your body is in a position for the most power.
"What is questionable?" is a very good question but if the anchor is that bad I'd skip it. There's always a better one somewhere nearby.


csproul


May 5, 2006, 7:20 AM
Post #16 of 28 (3208 views)
Shortcut

Registered: Jun 4, 2004
Posts: 1769

Re: Belay methods on a marginal anchor? [In reply to]
Report this Post
Average: avg_1 avg_2 avg_3 avg_4 avg_5 (0 ratings)  
Can't Post

In reply to:
In reply to:
Dude, you have it ass backwards.
Me? No, I don't.

I can give you a very thorough explanation if I wish. It's pure physics. Weight, pulleys, friction and counterweights. If you belay directly off the anchor, you'll eliminate the counterweight. It's pretty simple really.
First of all I think some people are talking about belaying a second and some are talking about belaying a leader with a marginal anchor. The logic for not belaying off the anchor goes something like this: The anchor itself may not hold a fall, but a belayer with a good stance may be able to take the bulk of the fall with his/her body and have the anchor help hold them in place (and yes I have done this successfully many times). If belaying straight off the anchor, and it fails, you have little hope of stopping either one of you. Unless you are redirecting the belay, there is no counterweight.


ontherocks


May 5, 2006, 8:08 AM
Post #17 of 28 (3208 views)
Shortcut

Registered: Sep 3, 2001
Posts: 155

Re: Belay methods on a marginal anchor? [In reply to]
Report this Post
Average: avg_1 avg_2 avg_3 avg_4 avg_5 (0 ratings)  
Can't Post

I think the rule of thumb is: if your anchor is questionable, belay of your harness. Your body will act as an screamer to protect the anchor.

In reply to:
I wouldn't want to catch a factor 2 fall that's pulling straight down on my hips! F*ck that!

If the anchor take the fall, the anchor, and then you would fly out (and down). Then your only option is start lowering/belaying with your knife ready, close to the rope. I wouldn't like to be belayed with someone with that mindset.

In reply to:
Say you belay straight off your harness. Climber takes a factor 2 fall onto you...rope slams down against your leg/ foot or something...pulls you out of your stance...you now have 2 climbers falling onto the anchor, both in relativly high factor falls (depending on the belayers attachment to the anchor: sling, or rope) so I think that'll end up being around 4kn on the anchor, except with both the belayer and climber getting thrown around.

You should be attach in short to the anchor, then when you get the fall, you reduce the shock load over the anchor before the anchor takes the blow. The belayer is not falling on the anchor, she is part of it. That's the base of the whole misunderstanding.

In reply to:
I'd hope you could build an anchor that'd hold at least 6kn...that shouldn't be TOO hard.

That's the point of the question. That you can't get a good anchor. Think A6.

In reply to:
IN this particular situation, the belayer should be attached to somethign else besides the ancor, because if the lower pulls the anchor, the belayer is dead as well as the loweree.

If there is something else, then you do have a good anchor (the "something else"). If the "something else" is equally questionable, then include it as part of the anchor, to strengthen it. If it's worse, then don't use it and attach yourself to the anchor.


dirtineye


May 5, 2006, 8:54 AM
Post #18 of 28 (3208 views)
Shortcut

Registered: Mar 29, 2003
Posts: 5590

Re: Belay methods on a marginal anchor? [In reply to]
Report this Post
Average: avg_1 avg_2 avg_3 avg_4 avg_5 (0 ratings)  
Can't Post

What you do not understand is that you have a responsibility to save yourself.

If you are attached to a crap anchor when you could have had an independent stance, then you have killed yourself and your partner if the anchor goes and you go with it.

YOU need to be able to free yourself from this potential disaster.

The something else might just be a stance.

But by all means, feel free to take the glory ride with your partner, don't let me stop you.


mcfoley


May 5, 2006, 9:03 AM
Post #19 of 28 (3208 views)
Shortcut

Registered: May 15, 2002
Posts: 644

Re: Belay methods on a marginal anchor? [In reply to]
Report this Post
Average: avg_1 avg_2 avg_3 avg_4 avg_5 (0 ratings)  
Can't Post

In reply to:
I think I would belay off my harness in all situations where the anchor is questionable.

Ditto on this...


fishbelly


May 5, 2006, 9:25 AM
Post #20 of 28 (3208 views)
Shortcut

Registered: Oct 31, 2004
Posts: 273

Re: Belay methods on a marginal anchor? [In reply to]
Report this Post
Average: avg_1 avg_2 avg_3 avg_4 avg_5 (0 ratings)  
Can't Post

Belaying from your harness! Make the whole situation more personnel.
Kind of takes the sport out of it.
As the be layer you are part of the anchor. Not a casual observer.


jimdavis


May 5, 2006, 7:16 PM
Post #21 of 28 (3208 views)
Shortcut

Registered: May 1, 2003
Posts: 1935

Re: Belay methods on a marginal anchor? [In reply to]
Report this Post
Average: avg_1 avg_2 avg_3 avg_4 avg_5 (0 ratings)  
Can't Post

In reply to:
In reply to:
I'd hope you could build an anchor that'd hold at least 6kn...that shouldn't be TOO hard.

That's the point of the question. That you can't get a good anchor. Think A6.

IF I ever put myself on an A4 and up, route, the bolt kit is coming along with me.

There's no reason to ever want to belay someone off of such an anchor. Downclimb to something suitable, or simul-climb up to something suitable.


majid_sabet


May 5, 2006, 8:04 PM
Post #22 of 28 (3208 views)
Shortcut

Registered: Dec 12, 2002
Posts: 8390

Re: Belay methods on a marginal anchor? [In reply to]
Report this Post
Average: avg_1 avg_2 avg_3 avg_4 avg_5 (0 ratings)  
Can't Post

If I had to belay or lower a cargo on a questionable anchor, I would try to minimize direct risks on myself and I would belay directly from anchor incase things go wrong


horseonwheels


May 5, 2006, 10:05 PM
Post #23 of 28 (3208 views)
Shortcut

Registered: Feb 2, 2005
Posts: 226

Re: Belay methods on a marginal anchor? [In reply to]
Report this Post
Average: avg_1 avg_2 avg_3 avg_4 avg_5 (0 ratings)  
Can't Post

I think with any questionable situation, the climbing team should be together. There shouldn't be one person that takes a lot more of the risk than the other. Therefore, if there is a solid stance....belay off the harness. If the belayer is depending on the anchor as well....belay off the anchor.

I don't think you could say that one way is better all of the time. Also involved in this is finding the absolutely best possible anchor spot.

Do whatever has the best chance of protecting your team the best, and forget about the belayer being able to save himself if things go wrong. Any belayer that ties a knot in the slack end of the rope is making a statement that theyre not letting go of their partner.

(as an amendment to the previous idea... if your partner tricks, sandbags, or bullys you into getting on something you shouldn't be on, i might not feel so guilty about belaying off the anchor or not tying that stopper knot)


kman


May 5, 2006, 10:25 PM
Post #24 of 28 (3208 views)
Shortcut

Registered: Oct 16, 2001
Posts: 2561

Re: Belay methods on a marginal anchor? [In reply to]
Report this Post
Average: avg_1 avg_2 avg_3 avg_4 avg_5 (0 ratings)  
Can't Post

In reply to:
In reply to:
I think I would belay off my harness in all situations where the anchor is questionable. Try to find a good stance where your body is in a position for the most power.
There's always a better one somewhere nearby.

Must be nice :lol:


Partner rgold


May 5, 2006, 10:26 PM
Post #25 of 28 (3208 views)
Shortcut

Registered: Dec 3, 2002
Posts: 1804

Re: Belay methods on a marginal anchor? [In reply to]
Report this Post
Average: avg_1 avg_2 avg_3 avg_4 avg_5 (0 ratings)  
Can't Post

The situation, at least for belaying or lowering a second, depends on how good a stance is available. Modern climbing has emphasized anchors to the point that the basics of braced belaying are no longer common knowledge (except in the canyoneering world), but there are many situations that will allow a perfectly safe harness belay for a second, with the result that falls can be held and lowering accomplished with absolutely no load on the anchor.

If a decent braced position cannot be found (assuming the leader knows how to spot them---they may be located in a place with no anchors), then downclimbing and/or simulclimbing to better anchors are options that have to be weighed along with using the anchor. If the anchor must be used, then an attempt to equalize the pieces as much as possible should be made, and as long a tie-in as feasible should be employed to provide some dynamic cushion for the anchor.

In such a situation, I think putting the device directly on the anchor is a bad idea and redirecting the belay through the anchor is a really terrible idea. Any bracing a climber can accomplish with their feet could potentially take some load off the anchor and so a harness belay is the best option. The second must be alerted to the fact that they must climb as if they are on an unprotected lead and cannot fall. The second and belayer must coordinate to make sure that not even a little slack develops in the rope as the second climbs.

The real stress occurs when the second joins the leader and the next pitch must be lead with the belayer at a poor anchor.

First page Previous page 1 2 Next page Last page  View All

Forums : Climbing Disciplines : Trad Climbing

 


Search for (options)

Log In:

Username:
Password: Remember me:

Go Register
Go Lost Password?



Follow us on Twiter Become a Fan on Facebook