Kalymnos Anchor Failure

Another option I've thought about (and done) is to not get lowered off.  Clean the route on rappel.

Whew.  Scary stuff.

It's a bit of thread drift, but why not.  I don't know about the route in question, but a lot of the routes in Kalymnos are too steep to practically rappel off of.  Many of them would be borderline unsafe to try and clean that way.  As to the prusik technique, I saw a similar comment on the Rebolt Kalymnos IG post and I'm skeptical that a prusik would catch a fall that big.  I'm pretty sure it would either break or slip, but am open to being proven wrong.

Clint Cumminswrote:

Cut threads are more prone to breaking.

To expand on this, there are cut threads and rolled threads. Rolled threads create residual stresses, usually compression stress at the root of the threads. By comparison, cutting threads doesn't cause any additional residual stresses in the bolt. The residual stresses caused by rolling threads might make the bolt more susceptible to corrosion. Since the residual stress is in compression, it can actually increase the strength of a bolt loaded in tension. The compressive residual stress at the thread root also inhibits the development of fatigue cracks and fatigue failure. Bicycle spokes are always rolled because rolled spoke are less prone to failure and because rolled threads are cheaper and easier to do.

"Results show that thread rolling significantly improves fatigue strength"

Investigations On The Fatigue Strength Of Threads Produced By Different Fabrication Techniques

Thanks for the correction, Dan.  I corrected my post.

Clint Cumminswrote:

Thanks for the correction, Dan.  I corrected my post.

Clint, you were correct. Cut threads are weaker.

Dan, I have only heared the opposite around rolled threads when it comes to corrosion, that they are less susceptable.

Brian in SLCwrote:

Another option I've thought about (and done) is to not get lowered off.  Clean the route on rappel.

Whew.  Scary stuff.

How would rappelling protect you from an anchor failure?

Prusik seems like the way too go as you're then blacked up by all the draws/bolts you haven't cleaned yet. Although managing the prusik while cleaning a very steep route might be quite difficult.

As to Max's point about the prusik holding a big fall, the fall shouldn't ever really be bigger than the distance between bolts and force would be limited by the dynamic rope in the system.

Super scary stuff, 3 bolts failing 2 of which under basically body weight is hard to wrap your mind around.

Blake Mwrote:

How would rappelling protect you from an anchor failure?

its the weight of only 1 person. When you lower the top gear is taking you AND the belayer

Prusik seems like the way too go as you're then blacked up by all the draws/bolts you haven't cleaned yet. Although managing the prusik while cleaning a very steep route might be quite difficult.

As to Max's point about the prusik holding a big fall, the fall shouldn't ever really be bigger than the distance between bolts and force would be limited by the dynamic rope in the system.

Super scary stuff, 3 bolts failing 2 of which under basically body weight is hard to wrap your mind around.

Makes me think about who lowered down before them and how insane it must feel to dodge that bullet.

No shade on the fallen but the lesson here is that especially in a Marine environment you are rolling the dice if you see a spec of rust/anything other than titanium, imo.

In the mountains we can trust all SS hardware, but galvanized or mixed metals are just plain sheit as we saw in Owens River Gorge with a fatality there from seemingly good-looking hardware.

I would say BUYER BEWARE and be prepared to replace anchors yourself as the consequences can be the worst possible outcome. If you are dependent on other's gear for your safety when climbing, then you are rolling the dice with unknown odds. Take responsibility for your own safety, imo. We used to carry bolt kits on big walls or other adventure climbs. I would say one in the pack at least in a marine environment so a bolt could possibly be added before lowering off of shit. Add a bolt to the anchors if in doubt.

My sincere condolences to all affected by this tragedy.

Max Tepferwrote:

It's a bit of thread drift, but why not.  I don't know about the route in question, but a lot of the routes in Kalymnos are too steep to practically rappel off of.  Many of them would be borderline unsafe to try and clean that way.  As to the prusik technique, I saw a similar comment on the Rebolt Kalymnos IG post and I'm skeptical that a prusik would catch a fall that big.  I'm pretty sure it would either break or slip, but am open to being proven wrong.

Lowering off is common for the correct assumption in your post and for routes starting from raised terraces.

The prusik based method is Petzl endorsed and requires 7mm dynamic cord for the loop.

Document link here:

https://web.archive.org/web/20120311135917/ petzl.com/files/all/en/acti…

Francis Hadenwrote:

That link didn’t really work for me, but I’ll try on my laptop later as I’d be curious to see it.  I’m still skeptical that a 7mm cord is going to grab well on a skinny sport climbing rope in the context of a 20-30’ lead fall. 

Mr Rogerswrote:

its the weight of only 1 person. When you lower the top gear is taking you AND the belayer

Not quite, when lowering the anchor is taking the 2x the weight of the climber. 

Max Tepferwrote:

That link didn’t really work for me, but I’ll try on my laptop later as I’d be curious to see it.  I’m still skeptical that a 7mm cord is going to grab well on a skinny sport climbing rope in the context of a 20-30’ lead fall. 

I'd rather use a 30cm dyneema sling with a friction hitch. It's just as strong and much more likely to grab. See here (in German, but you can use any tranlation tool): bergundsteigen.com/artikel/…

Allen Sandersonwrote:

Not quite, when lowering the anchor is taking the 2x the weight of the climber. 

I beleive you misinterpreted my commment. We agree.
When rapping its only the weight of the rappeler.
When lowering, you have both the climber and belayer weight.

Mr Rogerswrote:

pedantic interjection: it's closer to the climber's weight(x2), assuming the belayer isn't being pulled off the ground

A 10,000 lb belayer standing on the ground wouldn't add any additional strain to the anchor bolts while lowering a typical weight climber as compared to a typical weight belayer.

Carry on,

Mr Rogerswrote:

I beleive you misinterpreted my commment. We agree.
When rapping its only the weight of the rappeler.
When lowering, you have both the climber and belayer weight.

No misinterpretation of your latter statement, it is wrong. As such, we do not agree. When lowering, there is twice the climber weight on the anchor. The belayer's weight does not factor into the equation. The belayer could tie the rope off to a tree a walk away. Or as noted above weigh 10,000 lbs.

I’d like to point out that rappelling off of sport routes results in much more frequent accidents then just lowering. Also, who is to say that the anchor would not have failed on lower? Perhaps it wouldn’t in this instance, but would fail at a later time for a different climber.

Maybe the lesson here is to use the appropriate hardware rather than revisiting the debate over rappelling versus lowering off of sport routes. 

I was insinuating the weight of the belayer is adding weight to the system ya lovely pedants. lol.
How pedantic do we want to get? its actually less than 2x climber weight due to friction at the turn...

Max Tepferwrote:

That link didn’t really work for me, but I’ll try on my laptop later as I’d be curious to see it.  I’m still skeptical that a 7mm cord is going to grab well on a skinny sport climbing rope in the context of a 20-30’ lead fall. 

Hi Max,

I tried opening the link and it did n't work so attached a screenshot below.

Zoom in on the right and Petzl state they tested this on a 9.7mm sport rope. Still requires any individual to assess the risk and employ this however.

Gregger Manwrote:

pedantic interjection: it's closer to the climber's weight(x2), assuming the belayer isn't being pulled off the ground

A 10,000 lb belayer standing on the ground wouldn't add any additional strain to the anchor bolts while lowering a typical weight climber as compared to a typical weight belayer.

Carry on,

When a climber is rapping down, force the anchor  is seeing is his body weight - Force= ( mass * (free fall accel))

When a climber is being lowered, the anchor is experiencing pulley effect - worst case 2x body weight. Best case is more difficult to estimate since anchor friction comes into play, but I would back-of-the-envelope guestimate 1.5 body weight loading on anchor.

If you care to go beyond dumb jokes - look up capstan equation, and Newton's laws.

Brian in SLCwrote:

Another option I've thought about (and done) is to not get lowered off.  Clean the route on rappel.

Whew.  Scary stuff.

It's not clear that those bolts would have held a rappel.