[mrjonathanr]

My second fumbled a cam from the top of Suicide Wall at Cratcliffe.

Now I've considered retiring the thing. No newly visible damage (it's always looked battered). A 40' fall-  I wouldn't consider it. But 80' directly onto rock...wondering if the axle - which isn't visible- might potentially be weakened.

 It's a very old HB, its  time may have come. Or then again, not. Any thoughts, oh wise heads of ukb? Sensible precaution or unnecessary fussing?

Thanks 

[dunnyg]

I would probably keep it. I only very reluctantly retired a cam, after being told if I fell on it then it would rip apart. That was with a fracture round some rivet, which wasnt overly obvious. It was a friend who inspects metal work as a job who pointed it out, and I didnt really trust it after that.

Maybe use it as an excuse to get a new one, but keep the old for when you need all the cams you can get when you go to the states and something is better than nothing?

In conclusion to the ramble, it will probably be allright, maybe stick it in somewhere and hang off it/test it to restore faith...

Disclaimer- you will probably die if you take any of this advice, I am in no way an outdoor professional and  my advice is entirely anecdote based

[TobyD]

bin it.if in the slightest bit of doubt, bin it.

[DAVETHOMAS90]

There are a lot of moving parts in a cam, aren't there? Just thinking about the impact, and the likelihood of the shock being dissipated. I can imagine it being more potentially damaging to a krab. You could contrive a drop-test. I've never understood the logic of body-weight testing placements. I'd probably keep it.

What's there to hit beneath Suicide Wall?

Hope you had a good time, bet it was lovely!

[deacon]

It doesn't really matter wether it's still strong or not, you've already doubted it and the thought of it'll come back to haunt you every time you use it.
Having some nice new cams does wonders for your confidence and tbh if they're HB's you must have had your money's worth by now

[Muenchener]

You could contrive a drop-test. I've never understood the logic of body-weight testing placements. I'd probably keep it.

I read on American forums, where they obsess about this sort of thing, that if a cam holds bodyweight or a firm pull with a hand, then it should hold a fall too. To do with the physics of how the camming works. But that's more about testing the placement than the mechanical strength of the cam itself.

I'd probably keep it too. I still have the first Friend I ever bough, a rigid stem 2.5 vintage ca 1980. It probably wouldn't work that well any more though - it's never been dropped but several spots on the lobes are worn flat.

[Fultonius]

Get on a rope on a short climb, place the cam, clip to it with a sling, give a decent bounce test. As Muenchener says, if it holds that it should hold a fall. The metals used for cams etc. are not brittle so if it isn't obviously bust then it should be fine.

I dropped my brand new #4 camalot about 150m (not that it matters much beyond 75m or so due to reaching terminal velocity - once upon a time I'd have been able to construct the equations of motion from scratch and actually work that out, it's funny what you quickly forget after passing the exams.)

Anyway, back to the story - dropped it from 150m onto a big sloping slopey slope and was sure it was lost to the glacier below but my mate Sandy went in search and came up trumps - a few dings and the cam lobes are a wee bit more shoogly than when new but it functions fine so it still goes on my rack.

Shoogly, what a wonderful word.

[Muenchener]

I dropped my brand new #4 camalot about 150m (not that it matters much beyond 75m or so due to reaching terminal velocity - once upon a time I'd have been able to construct the equations of motion from scratch and actually work that out, it's funny what you quickly forget after passing the exams.)

The only bit of school physics I have retained is the ability to calculate how long it took me to fall a given distance.

[mrjonathanr]

Thank you for the replies.

S= ut+0.5 x at x t iirc

[Muenchener]

Precisely. And if you know S (roughly) and U is approximately zero (fractionally negative if you happened to be dynoing upwards?) then you can derive T

[Johnny Brown]

There is no simple answer. It might be damaged, it might not be. I've seen stress fractures in ice axes but not trad gear, so there is unlikely to be a way of knowing without pull testing to destruction. If it landed on rock I would retire it.

The stuff about holding bodyweight sounds like bollocks. You can generate 3-4 kN bounce testing but that is a fair bit short of what it might be subjected to in a fall - the top piece gets close to double the normally quoted force remember.

I'm not an engineer but I have been teaching this stuff for a living for fifteen years.

[andyd]

bin it.if in the slightest bit of doubt, bin it.

+1

[danm]

Johnny is about right. You're not going to generate enough force in a bounce test to find out anything meaningful, other than whether the placement is any good or not. If there are no visible impact marks, and no evidence of distortion of any of the parts, and the cams still operate smoothly, then it's almost certainly going to be OK. It is however a great excuse to go and buy a shiny new cam - go on, you know you want to. Nice new kit and piece of mind, win win.

[Snoops]

As others have said, retire it. It's old and now your concerned. To climb well, you need gear confidence - get a new one.

[Obi-Wan is lost...]

Try and imagine how you'd feel if it fails and you or someone else gets hurt? Still too tight/skint to drop £50 on a shiny new one? If you're questioning it you need to replace it, degree in metallurgy or not. Also I would dismantle it so someone else can't start using it not knowing it's history.

[Will Hunt]

Obviously it should be replaced. The stuff about testing cam placements by a pull/bounce is complete and utter horse shit (of course). A friend imparted this advice to me once and I told him such. He continued to take it as gospel. He's since had a trip to the hospital and I don't believe he puts any store by that little chesnut anymore.

[Fultonius]

Do you lot ever actually get out in the real world or are you safe and sound in a padded cell?

Clearly a bounce test doesn't test it right up to the rated limit, but I very much doubt a damaged cam that can hold 3kn is suddenly going to fail at 5kn. Each to their own, I'm happy enough using it but wouldn't sell it.

. He's since had a trip to the hospital

Due to a dropped piece failing? If so, inform the UIAA and BMC because that's quite important information!

[mrjonathanr]

Thanks all, interesting to hear your views, especially those with relevant experience.

I think the reason this gets periodically debated is that there is no way of providing a definitive answer except retrospectively.

I think the cam is probably okay, but it could also quite possibly be compromised after falling ~25 metres onto a slab. I would never consider relying on it as a key piece of (non redundant) gear now.

It needs retiring.

Btw it was a nice end of day route Dave, but not quite the romp I expected after 4hrs bouldering and a month off getting fatter not fitter. May need help reversing that equation

[Will Hunt]

. He's since had a trip to the hospital

Due to a dropped piece failing? If so, inform the UIAA and BMC because that's quite important information!

Due to a cam ripping, presumably which had withstood a cursory tug and was therefore "bomber"

[Fultonius]

Well the guy's a muppet then.

As everyone has said, if you're not happy with it then it needs binned. End of story.

It's a shame there's not a definitive test, but there's not. Well, certainly not one that leaves the piece usable. 

[dunnyg]

Why is testing a cam horseshit will? Get off your bullshit high horse. When was the last time you saw a cam, I didnt think you would need them on all those highball LGP's you have been despatching recently...

[Falling Down]

I'd use it carefully, safe belays, easy ground, back up placement etc. certainly not as the last piece of gear before a crux runout. 

[Johnny Brown]

Do you lot ever actually get out in the real world or are you safe and sound in a padded cell?

Clearly a bounce test doesn't test it right up to the rated limit, but I very much doubt a damaged cam that can hold 3kn is suddenly going to fail at 5kn.

I get out a lot in the real world, but I rarely take a test rig or a load cell with me. Having done lots of testing in the lab, I know it's very common for metal items to show no problems at one load but suddenly fail at less than double that load. That's the nature of the metals used in climbing gear.

What 'real world' experience are you basing your presumption on?

[Fultonius]

I wasn't so much aiming at you Johnny -  your points seem valid.

I remember when I was at uni (Mechanical Engineering, Strathclyde) my supervisor had a few projects running when I was doing my 4th Year thesis. One of them was "testing the breaking strength of climbing karibiners" which I thought was totally pointless, as they're very well tested in industry. It's a shame he didn't go for "failure strength of cams dropped from various heights".

Who do you do testing for? Could be a worthwhile project.

[Johnny Brown]

I don't have access to a proper rig any more, though I could break the odd thing if required. I did some contract research for the HSE when they first looked at rope access, and then teaching PPE we usually break a few things.

Gear is only well tested at the point of sale. As they age they generally do quite well but you get exceptions, especially when abused. Which are interesting, and rarely reliably predictable.