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PostPosted: Thu Nov 28, 2013 8:24 am 
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In the early 1970’s Ray Jardine conceptualised a spring-loaded camming device as a means of protecting rock climbs; within the same decade Mark Vallance formed Wild Country and with Jardine’s input they took the prototype ‘camming device’ they affectionately named the ‘Friend’ into production. Other manufacturers soon caught on and began producing a range of camming devices with subtle differences but essentially the same primary function. These innovative pieces of equipment revolutionised the way we protect ourselves whilst climbing and the versatile camming device (often abbreviated to cam) is now commonplace on climbing racks around the globe!

In 2012, two camming devices were returned to the manufacturer after they failed the owner’s routine inspection. The manufacturers kindly forwarded the remains of the devices to the BMC Technical Committee for a further independent analysis and the dissemination of this information to BMC members.

On occasions, equipment fails. Even the high quality precisely engineered camming devices on the market today are prone to degradation and eventual failure. It is the aim of this article to investigate one aspect of camming device failure and to draw a number of key learning points along the way.

Have you checked your camming devices recently?

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PostPosted: Thu Nov 28, 2013 1:18 pm 
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Alarming indeed.
I have often though that the point that the flexible stem enters the rigid part of the cam would be a weakness and that manufacturers should do something to reduce the repeated bending load at such an acute point.
eg a semi flexible collar at the point of attachment


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PostPosted: Thu Nov 28, 2013 2:23 pm 
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I have had the unpleasant experience of taking a relatively soft fall onto a "camming device" only to have the cable pull straight out of the sleeve. My belayer said that the rope was barely tight when it happened. So, these things can, and do, fail. No visual inspection would have given any clue in this case.


Last edited by Richard on Fri Nov 29, 2013 5:37 pm, edited 1 time in total.

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PostPosted: Thu Nov 28, 2013 2:37 pm 
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Jeez Richard, you really do break everything ;)

I recall hearing a story many years ago about a cam failing under minimal load... what year did this happen?

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PostPosted: Thu Nov 28, 2013 5:47 pm 
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Richard wrote:
only to have the cable pull straight out of the sleeve


The cams end, or the rope end? How old was it and what type? Be interested to see pi of failure point.


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PostPosted: Fri Nov 29, 2013 9:26 am 
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I imagine nuts and wired hexes are subject to the same problems regarding bending of the wire. Also slings on normal hexes.

Something that has always worried me about cams - I always am slightly fearful of the fact that reliance is placed on a spring. This and the fact that the last time I placed a cam was near the top of Adam's Apoplexy at Monteseel, in the top crack where there isn't (as) much pro aside from cams in the 7cm crack. While placing the cam the one spring broke. Its a 15m route and I placed 20 pieces between the 2 ropes, so I don't think gear failure would have caused major injury, I also got a 10 BD nut in 1m higher in a real bomber - but still worrying.

There is no gear I feel more confident about than hexes - when I twist a size 10 into a deep crack I feel like it would only fail if the rock failed...

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PostPosted: Fri Nov 29, 2013 11:02 am 
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Sorry Gaz but the load is meant to go through the lobes into the stem area & the geometry is meant to ensure that in fact the force you pull on the stem is the force that is transferred through the lobes into the rock. The spring serves no function with regards the forces - only to hold the lobe in place.

The new X4 in fact has little rings to protect the stem. Personally anyone who knows about this stuff should not be surprised those cams in the article failed where they did - at the stress raiser - so no surprises there. Also those were very old technology (I have used cams like those but nothing nowadays is made like that). So I agree with keeping an eye on all of your gear but lets not have creeping paranoia about Cams. Frankly we are very fortunate that the climbing industry is one where safety comes first & greed (to a large extent) second - pity about all the cheap biners of dubious quality from China though (that's where I would direct all my paranoia...)

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PostPosted: Fri Nov 29, 2013 11:07 am 
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Old Smelly wrote:
Sorry Gaz but the load is meant to go through the lobes into the stem area & the geometry is meant to ensure that in fact the force you pull on the stem is the force that is transferred through the lobes into the rock. The spring serves no function with regards the forces - only to hold the lobe in place.


I do understand that - my point though is that if the spring fails the device fails. Perhaps as you fall you pull the cam sidewards and the connection between the spring and the lobe fails the device could fail (although the opposing side presumably would hold). By definition a spring is pulled tight and loose through use - thus wearing the metal.

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Last edited by Ghaznavid on Sun Dec 01, 2013 7:05 pm, edited 1 time in total.

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PostPosted: Fri Nov 29, 2013 4:46 pm 
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Ok let me get this right...buy Hexes because when the Camalot wears out it will break? Can you get a picture of the spring that broke? I have seen a trigger wire fail but a cam spring? How old was that Cam?

Hmm I dunno if you got the point of the article Gaz. The real point is that those really old cams broke because that is what stuff does when it wears out or to put it another way - we are lucky that the Engineering that goes into the design of Cams is generally done by people who know what they are doing & so do not put springs in that break long before the rest of the product wears out...The trigger wires are another story but they are not safety critical...but the springs pulling out at funny angles...too much "Vertical Limits" in your diet I think...

All quality Cams are tested to a rated strength that they pull at. Ok this varies but even then the unit does not generally fail because a spring breaks. If this was the case you would hear of these springs breaking all the time. There must be more to your story (sounds scary all the same).

What I am getting at is if you don't trust the Engineering & the tests then certainly do not use Cams, otherwise do not worry about the spring as it will have been designed not to fatigue & break (and there must be an explanation or inquiry regarding the spring that did fail on you). Personally I think your paranoia is misplaced considering the horrible Drakensberg rock you climb on... that will fail long before any cam :thumright

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PostPosted: Fri Nov 29, 2013 5:35 pm 
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I can't recall exact date. Sent it back to Wild Country. Probably early 90's. Came out at cam end. Cams were still perfectly placed in a rail (0.5 Flexi Friend) and I was on the ground about 10m below! A nut took most of the impact as I hit the ground. Hobbled down from Tafelberg. Wild Country replaced the cam but were quick to suggest, despite accompanying photos of placement, that I must have used it incorrectly. Needless to say, I lost all faith in Wild Country flexible cams, and have used BD and Metolious ever since!


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PostPosted: Sun Dec 01, 2013 7:08 pm 
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Old Smelly wrote:
Hmm I dunno if you got the point of the article Gaz.


I think that is a fair assessment :lol:

The cam was old and I take the point that no gear is any use if you don't inspect it.

Forgot rule no 3 of online forums - don't post when you are busy packing for a hike. Just got back from a monster 2 day hike at Mnweni, about 40km long and 2km up and 2km down. Epic but tiring...

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PostPosted: Mon Dec 02, 2013 8:58 am 
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Richard wrote:
Probably early 90's. Came out at cam end. Cams were still perfectly placed in a rail (0.5 Flexi Friend)


Hey Richard,

I assume it was one these then (below - it used to have a pink sling). I recall hearing about your incident.
There is a resin/glue over where the cable inserts into the metal (on both sides). If there was any wear, I doubt very much that you would see it during an inspection!

Here is a report on WC cams that have broken at the cable/stem connection point Wild Country Technical Friends stem cable failures Incident Ref.07/12/L.HEI
The thing to remember is that trad gear does have a limited life!

My cam has just gone into permanent retirement :salut: (although I still trust my old solid stem friends :)


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File comment: Wild Country Flexi Friend 1990's
wild_country_flexi_old.jpg
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