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Banquo
climber
Amerricka
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Topic Author's Original Post - Nov 17, 2015 - 09:52am PT
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I'm thinking of three cases where 1/4" anchors would be acceptable to me. Perhaps not acceptable to you of course. I also think that if there are 1/4" anchors the route description should clearly state they are there so people can make there own decisions about safety. I would also like to see more comprehensive testing of 1/4" anchors with 1/4" hangers so the gear could be marked or listed with a capacity much like chocks and cams are.
1) Temporary placements on first ascents drilled on lead. These should later be replaced with 3/8" anchors by the first ascentionist.
2) Permanent placements on non "sport climbs" that are not expected to see a greater than 1.0 fall factor. These should be SS with SS hangers and would not be intended for repeated falls.
3) Preservation of historic routes. Old 1/4" anchors that have lost their original capacity should be replaced with new 1/4" anchors. Replacements should be SS with SS hangers.
UIAA standards require minimum capacities for various gear that can be expected to catch a lead fall. As I understand it, the required capacity for anchors is based on a worst case scenario of a factor 2 fall with a rigid belay. Some of the required UIAA capacities are:
Rock Anchors 25 kN shear, 15 kN pull out.
Basic Carabiner 20 kN
Oval Carabiner 18 kN
Cams 5 kN
Chocks 2 kN
Note that as little as 2kN is considered to be adequate in some cases.
In actual testing with a standard non-rigid belay, Petzl has measured and reported 6 kN for a factor 1 fall.
http://www.petzl.com/en/Sport/Forces-at-work-in-a-real-fall?ActivityName=Rock-climbing&l=US#.VktSmb-Dpuo
I have tested various 1/4" anchors in good granite. I have not exactly followed the test methods prescribed by UIAA For one thing the UIAA test method require tests in high strength concrete not rock. My granite is much stronger than their concrete. Also, my tests are to failure so consider my numbers high.
0.25x1.25 Powers Drive
Button head Split shank)
15 kN shear
0.25x1.50 Powers Drive
Button head Split shank
15 kN shear, 8 kN direct pull out
0.25x1.50 Powers Spike
13 kN shear, 5 kN direct pull out
0.25x1.75 Simpson Wedge-All 316 SS
11 kN shear 9 kN tension
0.25x1.375 wej-it 304 SS Sleeve
9 kN shear 4 kN tension
In the above "direct pull out" means the anchor was tested without a hanger and there was no prying. "Tension" means the test was done with a hanger which prys and increases the force on the anchor. A "tension" type test with prying is what UIAA requires. The UIAA test is of the hanger and the bolt so it seem that in use you should use the tested bolt with the tested hanger.
For comparison, Black Diamond lists the following:
Camalots: [0.3] 8 kN
[0.4] 10 kN
[0.5] 12 kN
[0.75-6] 14 kN
Stoppers: [size 1-2] 2 kN
[size 3] 5 kN
[size 4-5] 6 kN
[size 6-12] 10 kN
Wired Hexes: [size 1] 6 kN
[size 2-3] 6 kN
[size 4-11] 10 kN)
It seems to me that a good 1/4" anchor is probably stronger than a small cam and most if not all chocks and that a 1/4" anchor is viable protection in the right situation. Climbing on a route with 1/4" anchors requires a different level of commitment than a route with big, fat, new 1/2" bolts does so perhaps in preserving a climb maintaining the original type of protection should be considered.
Government agencies in Europe are beginning to regulate rock anchors. I hope we never go that route but it may be inevitable. Probably end up with code approved guard rails on El Cap bivy ledges.
John Krakauer has quoted Jon Barry as saying "If climbers didn't die, climbing would." I think it is true that the risk, and the fear, are part of the true game. If you want simulated risk, go to Six Flags. The quote comes from page 185 of Barry's book The Great Climbing Game which is a very good read. On page 186 Barry writes "If we choose this game and its dangers we should not complain if we, our friends or others fall victim to 'the fell clutch of circumstances'." Barry's quote 'the fell clutch of circumstances' comes from Henley's poem Invictus which ends:
I am the master of my fate:
I am the captain of my soul.
Climbing is dangerous. Climb at your own risk. Know your equipment and how to use it. Accept responsibility for your own safety.
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thebravecowboy
climber
The Good Places
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Nov 17, 2015 - 10:01am PT
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You make a solid argument for hardware in the same girth and style as the FA. I can dig it. But how does one address the presumably shorter life of 1/4"ers wrt rust, etc?
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SteveW
Trad climber
The state of confusion
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Nov 17, 2015 - 10:14am PT
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Back in the '60's and '70's!
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Vitaliy M.
Mountain climber
San Francisco
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Nov 17, 2015 - 10:31am PT
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Thank you for the info! Helpful stuff!
And a good question. How does the strength diminish over time? How many years have to pass for these anchors to become a real hazard vs something that is clipped for protection?
Interesting especially when there is a concern about old rivets on big walls. When they were placed they were protection. With time they become hazard. So when replaced, should they be replaced with new rivets or 3/8 bolts for the long term benefit?
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JimT
climber
Munich
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Nov 17, 2015 - 10:42am PT
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The UIAA Standard calls for 25kN radial and 20kN axial. The European Standard requires 25kN radial and 15kN axial.
Government agencies in Europe are beginning to regulate rock anchors. I hope we never go that route but it may be inevitable. Probably end up with code approved guard rails on El Cap bivy ledges.
te Here
The sale of anchors in the member states of the European Union has been controlled by means of the standard EN959 since 1996. This is in place to ensure the manufacturing of higher quality safety equipment is not undermined by cheaper, low-quality imports. You may install any garbage you like but selling it is illegal.
1/4" bolts come under "garbage" wherever they are :-)
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Clint Cummins
Trad climber
SF Bay area, CA
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Nov 17, 2015 - 11:18am PT
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How about for rivet ladders on aid routes?
1/4" hole, but probably not a deep hole, and something minimal that is not high strength.
Unrelated to the above -
You described SS bolts, but the Powers Drive is carbon steel.
The Powers Spike is available in both SS and carbon steel.
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Banquo
climber
Amerricka
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Topic Author's Reply - Nov 17, 2015 - 11:50am PT
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1/4" bolts come under "garbage" wherever they are :-)
That go for small cams and chocks too? Yes, I understand what standards are and what their purpose is. In fact I am on a standards writing committee for ASTM that is safety related but it isn't related to climbing. I have no problem having a standards based capacity stamped on a 1/4" anchor, in fact I would support it. I'm not sure the UIAA load standards are entirely rational. 2 kN for a chock, 5 kN for a cam and 25 kN for a rock anchor seems inconsistent. I do think that regulation has the potential to kill the spirit of climbing as I know it.
Powers Drive is carbon steel
Yes, I would only use carbon steel for temporary placements even though I've depended on some pretty old ones.
How does the strength diminish over time? How many years have to pass for these anchors to become a real hazard vs something that is clipped for protection?
Like any climbing gear, it won't get stronger with time. Stainless steel should last a long time here in California but I don't think anybody can say how long.
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cragnshag
Social climber
san joser
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Nov 17, 2015 - 12:12pm PT
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I am the master of my fate
Not for long. The government wants to be master of your fate, because it knows what's best for you. And the government gets bigger every year...
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JEleazarian
Trad climber
Fresno CA
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Nov 17, 2015 - 01:10pm PT
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Not for long. The government wants to be master of your fate, because it knows what's best for you. And the government gets bigger every year..
I would expand that, based on personal experience and reading threads on ST -- we all know what's best for everyone else. Just ask us.
I've placed my share of 1/4" Rawl split-shaft bolts in the early 1970's, when we considered them the standard - and Leeper hangers the most reliable. Mea culpa. I certainly see no reason why long bolt ladders in Yosemite need to be a succession of 3/8" bolts, but sometimes bitter experience has caused me to beware of any ancient bolts I find that look like the ones I placed 40+ years ago. I can usually remove them with my fingers.
At least one regular angle I overdrove in 1969 is still in place, however.
John
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Banquo
climber
Amerricka
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Topic Author's Reply - Nov 17, 2015 - 01:26pm PT
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we all know what's best for everyone else. Just ask us.
As far as climbing gear goes we are letting Europe tell us what's best.
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Steve Grossman
Trad climber
Seattle, WA
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Nov 17, 2015 - 01:35pm PT
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Well, you certainly see CE all over gear these days and I don't believe that is originally an American standard so the answer may be "Yes".
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Banquo
climber
Amerricka
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Topic Author's Reply - Nov 17, 2015 - 02:07pm PT
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Other than rusty or cracked anchor components, How many accidents involve rock anchor failure? If regulators want to reduce climbing injuries, training and education would be the route to go - or simply ban climbing like BASE jumping basically has been. Belay and rappel errors are the most common cause of climbing injuries.
Anchor failure contributed to just 2.5% of technical roped climbing victims for the RMRG. Notable anchor failures include the movement of an approximately 250-kg boulder that had been slung with webbing, the failure of a top-rope anchor as a result of the climbing rope being threaded directly through the anchor webbing, and the failure of an anchor built from webbing spliced together using masking tape, a common method used by manufactures when linking two ends of webbing together on a spool. The RMRG does not have any records of bolted anchor failures, although one incident involved the failure of rock surrounding a removable mechanical device used as an anchor. Data from both Yosemite National Park and Australia report anchor failures as the cause of climbing incidents as 1% or less.
Emphasis added.
http://www.wemjournal.org/article/S1080-6032%2812%2900109-3/fulltext
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looks easy from here
climber
Ben Lomond, CA
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Nov 17, 2015 - 04:01pm PT
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Always love your science threads, Banquo.
the failure of a top-rope anchor as a result of the climbing rope being threaded directly through the anchor webbing, and the failure of an anchor built from webbing spliced together using masking tape
Can't ban stupid...
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Banquo
climber
Amerricka
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Topic Author's Reply - Nov 17, 2015 - 04:35pm PT
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Always love your science threads, Banquo.
Thanks
The article above referenced a Yosemite specific (1987) article.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1026367/pdf/westjmed00132-0042.pdf
Mechanism of Injury
Falls suffered by the lead climber were responsible for the majority of injuries (66%, P < .05) (Table 1). Length of falls ranged from 0.6 to 244 m (2 to 800 ft; mean 13 m [43 ft], median 8 m [25 ft]). On 29% of leader falls, "protection" pulled out of the rock during a fall, resulting in a longer fall (mean fall length 17 m [55 ft]; P = .05). Only 12% of injuries occurred while "aid" climbing. Six climbers were injured (one fatally) while climbing without a rope, and seven were injured while descending without a rope. Rappelling contributed only 1 % of all injuries. There was one case of equipment failure when a protection bolt drilled previously into the rock pulled out under the force of a fall.
The paper reports 144 leader falls so that would be about 42 protection pulled out to 1 bolt failure. Generally there are multiple pieces pulled on a long fall so the number of pieces pulled might be much higher.
So, if standards writers want to improve climbing safety, perhaps chocks and cams are the place to start. The accidents occurred in the mid 1980's so gear and bolts (even 1/4" bolts) have improved since then.
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donini
Trad climber
Ouray, Colorado
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Nov 17, 2015 - 07:52pm PT
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I've found a place for three or four of them over the years. Had three climbers hanging from one in a brutal storm thirty feet below a Patagonian summit. Given certain circumstances there is a place for everything.
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bhilden
Trad climber
Mountain View, CA/Boulder, CO
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Nov 17, 2015 - 08:43pm PT
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Feel the love!
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Steve Grossman
Trad climber
Seattle, WA
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Nov 17, 2015 - 08:57pm PT
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Not for those pups...
WHY?
The responsible thing to do is clear. Phat stainless on freeclimbs.
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JimT
climber
Munich
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Nov 18, 2015 - 01:19am PT
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That go for small cams and chocks too? Yes, I understand what standards are and what their purpose is. In fact I am on a standards writing committee for ASTM that is safety related but it isn't related to climbing. I have no problem having a standards based capacity stamped on a 1/4" anchor, in fact I would support it. I'm not sure the UIAA load standards are entirely rational. 2 kN for a chock, 5 kN for a cam and 25 kN for a rock anchor seems inconsistent. I do think that regulation has the potential to kill the spirit of climbing as I know it.
The difference is a 2kN nut is your personal equipment and you know it may be of marginal use when you place it. A bolt is just a bolt and for the average climber they are all the same. Marking the strength assumes climbers can read, will read and are capable of understanding what they read, all of which seem optimistic considering some of the people out there.
The standards are rational though the numbers may not appear to be, they are based on what works most of the time from our experience.
Obviously rivet ladders and aid climbing are different but then they are no longer rock anchors anyway under the normal definition, personally I think rivet ladders are just aid-lite and would prefer they were replaced by hooking but thatīs just me.
Since the standard was introduced in Europe rock climbing has exploded in popularity, as it has in the USA since 1/4" bolts were no longer popular and replaced with something more substantial, some part of the "spirit" of climbing may have suffered but clearly as a sport it is moving on to new levels and appears to be alive and kicking.
From my experience of climbing in the USA compared with Europe Iīd say the spirit of climbing is more under threat from the land resource managers like the BLM, your grasping legal system and so on rather than a few useful standards regarding the strength of safety equipment which were anyway introduced by the climbing community rather than the regulators.
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HighDesertDJ
Trad climber
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Nov 18, 2015 - 06:15am PT
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Placing 1/4" bolts gives future generations service projects to make them feel useful and important. They are a gift to tomorrow's climbers.
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Banquo
climber
Amerricka
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Topic Author's Reply - Nov 18, 2015 - 07:24am PT
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The difference is a 2kN nut is your personal equipment and you know it may be of marginal use when you place it. A bolt is just a bolt and for the average climber they are all the same. Marking the strength assumes climbers can read, will read and are capable of understanding what they read, all of which seem optimistic considering some of the people out there.
I think that anybody who is too stupid to see the difference between a 3/8" bolt and 1/4" bolt is probably too stupid to understand what a 2 kN chock is good for.
JimT knows what 2 kN is but for the rest of you dum-dums, 2 kN is about 450 pounds. I can bounce test 450 lbs. 450 lbs is so small that it won't catch any realistic leader fall. Fall factor and anchor force are not directly related but 2 kN probably wouldn't be reliable for a fall factor greater than 0.01.
Anyway, if the concept behind any climbing gear is to protect the stupid, all lead protection should catch any imaginable fall. And we should have guard rails on belay ledges.
DMT-
If you ever want to do some remote FA's and set a few 1/4" bolts, I have lots of projects to do.
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