Gallery  Spray  News  Links  TPWD  Tyranny  Capitalism  Contact Us  Search  Hueco Info


Stress-corrosion cracking -The problem:

Over time (decades or less) a high-strength alloy steel bolt hanger can be weakened seriously by a crack that propagates slowly in the metal-eventually leaving a hanger that can be broken in a mild fall, or even by body weight. And such a stress-corrosion crack may be barely visible to the eye or hidden on the back side of the hanger.

Perhaps only one in a hundred of my hangers will have been weakened. But for a hanger in place, there is unfortunately no way to predict if and when such a crack may begin or how fast it will progress from a tiny to a major crack. It may take decades, or only years, depending on factors that are unknowable.

After several broken or visibly cracked hangers had been reported or returned to me, I obtained and tested 640 hangers that were apparently OK, from various rebolting projects. About 99% held around 3000 lbs. or more, but seven failed at substantially lower loads. This is an unacceptable risk. I want to see the potentially dangerous hangers removed-including the 99 percent that are not cracked, since there is no way to tell which they are. Or I want to see them smashed into uselessness as a poor second choice.

To say that climbers should just not trust those old bolt placements that use my hangers is an even worse choice. I have tried repeatedly to warn the climbing community, but climbers still often tell me they hadn't heard of any special danger.

The risk is there, and I need your help in passing the word and in getting those old hangers off the rock. Unfortunately, a cracked hanger may look sound; while many hangers that are seriously rusted or bent are almost as strong as new. Appearance can't warn us, and experience with other hangers of mine is not valid. If we see a long fall held, it's too easy to say, "Hell, these old Leepers are fine!" Indeed, most are fine; but some are dangerous.

Getting the word out:
If anyone has already been killed or seriously injured when one of my hangers broke, I would like to know about it, with details-so I can use the reality and sadness of it to help get the word out effectively.

In the future, if someone is killed or seriously injured, I would like to know about it right away, so I can participate in the analysis of the incident, if that's feasible. Please call me immediately at 303-442-3773. I don't want to see such accidents happen if they can possibly be avoided.

At present, I know of only one fatal broken-hanger accident, which is the triple-fatality rappelling accident on El Cap in 1978. The hangers were not mine, but the failure was of the stress-corrosion cracking type. A weakened hanger broke under the multiple body weight, plus gear. Unfortunately, the failure of just one of the two hangers dropped the party, because of how the rappel stance was rigged.

It is true that various hangers made by others, in ways that are similar to the methods and materials I used, have developed similar low-force stress-corrosion cracking after various life spans, and have in some cases cracked sooner than mine or with more certainty. These include some unlabeled hangers that look very much like mine but were apparently made by individual climbers. Certainly every hanger maker has expected or hoped that his practices would avoid any such problems.

But not talking about these cracked-hanger failures won't make them go away. There has been too much silence about all this. I hope we can spread the word. With your help, please, since full page ads are not really in my budget.

Other factors:
Catching heavy or frequent falls does not cause such a crack to start or to progress. At the end, though, when the hanger finally breaks in two, that can happen in a fall.

A loosely gripped "spinner" does not indicate a larger risk of failure (though it makes it inconvenient to clip in). On the contrary, steady, long-term stress is part of the process that can lead to crack propagation; and that stress can arise from the hanger being held too tightly against the rock so that the metal is slightly "dished." A non-spinner may actually prove more dangerous. And tightening a spinner may be counter-productive.

Corrosion and weather are factors in this cracking process, though cracked hangers have been returned even from the arid Southwest.

But trying to predict which hangers one encounters will not be weakened at any given time in any given climbing area is a long-odds crap shoot-and a deadly one.

Use them anyway? Back them up!
Don't count on a single hanger, without arranging a backup of some kind that will catch you if it breaks.

Obviously situations arise where we cannot instantly replace a hanger or a row of hangers, when they're encountered on a climb. Although 99 out of a hundred may be safe, most of us wouldn't want to take a one-in-a-hundred risk-or at least not too often. It may be that many of the chock placements we use have such risks, which we accept as better than having nothing; but we usually back them up somehow. In a similar way, no kind of bolt anchor warrants trusting it totally by itself.

A one-in-a-hundred hanger risk creates a bolt placement that is too risky to be used alone. Fortunately, a one-in-a-hundred anchor backed up by another one-in-a-hundred anchor becomes a one-in-ten-thousand anchor, and three of them makes a one-in-a-million anchor.

This kind of "safety multiplication" is at least as important as the load equalization people often talk about. One bolt will generally be strong enough, except in some extreme fall. Instead, the real risk is that a single anchor, by itself, may hold almost nothing, if something has gone wrong with that bolt or bolt placement, or its hanger.

It is important to realize that most of these cracked hangers may eventually reach a stage where body weight alone can break them.

But even if you guard yourself by using backups, the next climber may not. Too many of us trust bolts too much. I certainly have done so. Often. Please take that hanger off the rock for the sake of us who are uninformed or unwise.

Thank you.

Ed Leeper,
6112 Fourmile Canyon,
Boulder, CO

Editor's Note 6.18.04:
After reading Ed's full-page ads in Climbing and Rock & Ice, I realized that climbing webmasters could help Ed get the word out. I called him to ask permission to post the information; he answered right away and we had a great conversation. Ed is 66, cheerful and sounds healthy. He's a bit behind the times when it comes to the Internet, but is beginning to realize it's potential.

Ed was very interested in the failure of the Leeper hanger on Desperado; his first concern was for the climber (Dr. Waldeman) who enjoyed the thrilling ride to the next bolt below. I assured Ed that no harm was done and that we would try to get the remnants of the hanger to him.

You may be interested to know that Ed has extensive knowledge of physics and electromagnetism. He has published a book about how proper wiring and grounding can help suppress magnetic fields produced by power lines; his website is .

were made between 1962 and 1984.

MAYBE 20,000 to 40,000
are now still in place and look OK.

But ROUGHLY 200 to 400 HAVE CRACKS in the steel that seriously weaken the hanger-
mostly too small to be seen by a climber who clips in.

Each year SOME WILL
, while others
begin the slow cracking process.

, right now, to break even in a short fall.

Ed's full page ad in Climbing