Mountain Project Logo

Structural Failure of Black Diamond Ultralight Camalot Size 0.4 Resulting in Injury

rocknice2 · · Montreal, QC · Joined Nov 2006 · Points: 3,847

If you look closely there are gouges on two lobes. Both the inner and outer on the one side.

Furthermore, it's tough to flat out say that there is a design flaw. The gouges indicate an off axis pullout. Either sideways or a rotational one. It really hard to say how much force the cam experienced. Did it deform because it was gouged or was it gouged because it deformed? Chicken or egg?

Also the crack in that spot isn't plug and play. It's good but there are definitely spots where it flares, especially in the back and top and bottom. I seem to recall a .5 going in there but I'm not sure and could be wrong on the size.

To the OP, can you post some photos of the other lobes? And maybe higher resolution.
Healyje · · PDX · Joined Jan 2006 · Points: 422
slim wrote: i don't really agree with attributing all of this to a design flaw.  the cam isn't designed to be loaded on one lobe, which is fairly apparent in this case.
Well, that's certainly in the eye of the beholder - in the software world, some people would consider this a design feature as opposed to a bug.

Either way, it's hard to avoid on smaller double axle cams given the second axle has to have a travel path.
rocknice2 · · Montreal, QC · Joined Nov 2006 · Points: 3,847
Healyje wrote: Well, that's certainly in the eye of the beholder - in the software world, some people would consider this a design feature as opposed to a bug.

Either way, it's hard to avoid on smaller double axle cams given the second axle has to have a travel path.

I don't think a single axle cam would have faired any better considering the angle of was ripped out at. It obvious the cam was not aligned with the direction of the fall.

For a true design flaw your need to show this occurring at more realistic pullout angles.

I could argue that if placed in a flaring crack, at maximum retraction and aligned reasonably. The deacresed camming angle (due to flare) would increase the forces on the lobes. Causing them to deform, thereby increasing the camming angle to hold better in the flaring crack. I know this is a stupid argument but so is calling out design flaws for things they are not designed for.

I don't know how many C4 .4's have been sold but I imagine a huge amount. There's many many that have been whipped on even at full retraction. If there was a serious weakness you see this of evidence. I realize there is some that have experience deformation but not nearly to the extent that one would expect it it were a flaw. Plus you'd need to show that the dual axle cams failed to hold when they deformed, more often than Single axle cams get crushed and fail. Cams that hold but get damaged sometimes. The cam did their job and now it's time to retire it.
patto · · Unknown Hometown · Joined Jul 2012 · Points: 25
rocknice2 wrote:

I don't think a single axle cam would have faired any better considering the angle of was ripped out at. It obvious the cam was not aligned with the direction of the fall.

For a true design flaw your need to show this occurring at more realistic pullout angles.
That is a big call.
Healyje · · PDX · Joined Jan 2006 · Points: 422
rocknice2 wrote:

I don't think a single axle cam would have faired any better considering the angle of was ripped out at.

A single axle cam probably would have lost some metal off the cam lobe, but that's entirely different than the cam lobe collapsing.

rocknice2 wrote: It obvious the cam was not aligned with the direction of the fall.
Exactly, but irrelevant.

rocknice2 wrote:For a true design flaw your need to show this occurring at more realistic pullout angles.
All that matters is the cam lobe collapsed under compression, it doesn't matter how or why.
Rob warden The space lizard · · Now...where? · Joined Sep 2009 · Points: 0

So 9 pages later we can agree that finger sized cams somtimes break?  That ultralight gear has a more limited lifespan, and that more metal is in fact better on small cams? 

slim · · Unknown Hometown · Joined Dec 2004 · Points: 1,103
Healyje wrote: A single axle cam probably would have lost some metal off the cam lobe, but that's entirely different than the cam lobe collapsing.

Exactly, but irrelevant.

All that matters is the cam lobe collapsed under compression, it doesn't matter how or why.

but it does matter how or why.  if the cam failed (and by failed i mean pulled) when it was loaded in a manner that isn't consistent with how it was intended to be loaded then all bets are off.  it seems like folks are somehow thinking a single axle cam wouldn't have failed in this situation, but there are reports of single axle cams pulling at this location. having climbed this route, i know that the gear at this location is sub-optimal.  would i be surprised if i fell on a piece at this location and had the same outcome?  not overly.

i have a dozen .3's and a dozen .4s that have been abused for years and none of them show any signs of the excessive deformation of the lobes in this area.  sure, i have heard of this (i think tbubb had brought it up a long time ago).  i generally place small cams pretty tight, so i would guess that most of the time my placements have the contact patch in this general area.

i am still curious to see if there was any bending in the lobe or the axle.
phylp phylp · · Upland · Joined May 2015 · Points: 1,097

Wow, ten pages of discussion based on one post by the OP with a not very good picture.
I think it's time for an executive summary:
A climber voluntarily jumped onto a smaller piece in a possibly sub-optimal location. It popped, and sacrificed its life while trying not to pull. The climber flung himself into the path of the dying ultralight cam, which despite being ultralight, impaled the soft flesh of the climber, causing grievous bodily harm requiring stitches.
A larger cam, placed a few feet below in a universally acknowledged good placement, kept the climber from decking.  All things considering, a not so bad outcome.
At this point it is unclear whether the OP is going to ask Black Diamond to do some kind of analysis to try to figure out why the cam got mangled.
At this point it is unclear if these ultralight cams do perform according to specs, even though BD probably tested the F*&k out of them before putting them on the market.
At this point it is clear that some people like other smaller cams, like Totems and Metolius, better than Black Diamond (breaking news!).

Healyje · · PDX · Joined Jan 2006 · Points: 422

I wouldn't necessarily agree with any consensus on your first statement.

I'd agree with the second statement.

The third statement is more a matter of design - dual axle cam lobes are just going to have a different configuration than single stem cam lobes by design which clearly isn't an issue until you get down into small cam sizes where dual axles make less sense.

phylp phylp · · Upland · Joined May 2015 · Points: 1,097

Yes, Jake, I agree with what you said, it was just my attempt at a little humor.  I do think there has been a lot of good discussion and it's been quite interesting to read people's opinions.  And I have been impressed by how civil the whole discussion has been.  
Carry on!

cyclestupor · · Woodland Park, Colorado · Joined Mar 2015 · Points: 91

For what it's worth here's my takeaway from this thread....

#1 First and foremost, although rare, smallish double axle cams can and do deform when catching a fall due to the cutout in the lobe.  The cam must be retired if this happens.  According to the OP the inside of the cutout on his cam was rubbing on the axle.  The pictures posted by the OP are irrelevant and too low resolution to judge the deformation.  But if you believe what the OP has said, then the only way that can happen is if the lobe has deformed.  Even if you don't believe the OP for some reason...  There are others who have observed the same deformation of small double axle cams.

#2 We don't know how much force it takes to cause the deformation, or if the deformation reduces holding power.  The standard testing procedure doesn't require that cams are tested in the small part of their range, and they are tested in perfectly parallel cracks.  But this doesn't change #1.

#3 There is no way to know if the deformation caused the placement to fail.  The lateral gouges in the surface of the cam are evidence that the placement was probably marginal.  But this doesn't change #1.

#4 Single axle cams don't deform in the same way since they don't have a cutout.  There are of course other ways a single axle cam can break when it pops.  e.g. lobes umbrella causing trigger wires to break, springs to break... etc.  And of course any cam can develop gouges, or surface deformation if it pops (Aliens are notorious for this).  But in all likelihood, a UL C4 .4 will be permanently damaged with less force than it would take to permanently damage a comparable single axle cam (yes, this is pure conjecture).

In my mind, it doesn't matter if the cam failed because it deformed.  Hell it doesn't even matter if the OPs cam actually deformed or not.  The only piece of valuable information I am taking away from this thread is that deformation is a possibility.  I wasn't a fan of small double axle cams anyway and I am even less of a fan of UL C4s, so this fact doesn't really change anything for me.  I am still happy that I know of this possibility though.  Does anyone wish the OP had never started this thread?

Again...  Thank you for posting Brian.

Pavel Burov · · Russia · Joined May 2013 · Points: 50
Brian Braunstein wrote: Conclusion
Despite the fact you have gracefully ignored my previous question I am to ask yet one more. Have you sent the failed cam to the manufacturer?

To clarify. We are climbers. We want to know how solid and functional those little shiny pieces we rely on. We want to learn from any and every gear failure. 'cause we want to get back home from our climbing trips.
Healyje · · PDX · Joined Jan 2006 · Points: 422
slim wrote:

but it does matter how or why.  if the cam failed (and by failed i mean pulled) when it was loaded in a manner that isn't consistent with how it was intended to be loaded then all bets are off. 

We're talking two different things: a) the placement failing and b) the cam lobe 'failing' due to deformation under compression. The former is irrelevant whereas the latter is of some concern.

it seems like folks are somehow thinking a single axle cam wouldn't have failed in this situation, but there are reports of single axle cams pulling at this location. having climbed this route, i know that the gear at this location is sub-optimal.  would i be surprised if i fell on a piece at this location and had the same outcome?  not overly.
Again, the discussion isn't about the placement failing.

i have a dozen .3's and a dozen .4s that have been abused for years and none of them show any signs of the excessive deformation of the lobes in this area.  
Are they the new UL's? That's what's being discussed here.

i am still curious to see if there was any bending in the lobe or the axle.
There was compression 'bending' or deformation of the lobe which resulted in obstruction of the second axle's travel under that part of the lobe.

The OP didn't speak to any damage to either axle.

The incident could be a statistical fluke and there are just some circumstances where small BD UL cams will deform and pull. And those may be placements where a single axle cam could lose some metal off the cam lobe and also pull. The former may be of some concern to BD UL owners or not, but it's probably a good idea to back up any such placements.
NateGfunk · · Unknown Hometown · Joined Apr 2013 · Points: 50
Rob the tricam wrote: So 9 pages later we can agree that finger sized cams somtimes break?  That ultralight gear has a more limited lifespan, and that more metal is in fact better on small cams? 

Jfc yes exactly.

Bug Boy · · In my car · Joined Aug 2017 · Points: 81

If people want more techy climbing stuff to talk about here’s a single axle cam my friend also busted in Squamish. He believed the placement to be good and didn’t thing there where any crystals on the lobes. Ripped on a small (8feet total) whip. (Not a recall)


that guy named seb · · Britland · Joined Oct 2015 · Points: 236
Evan Mann wrote: If people want more techy climbing stuff to talk about here’s a single axle cam my friend also busted in Squamish. He believed the placement to be good and didn’t thing there where any crystals on the lobes. Ripped on a small (8feet total) whip. (Not a recall)

obvious partial umbrella, looks like the guy put it straight in and torqued it straight out.

grog m · · Saltlakecity · Joined Aug 2012 · Points: 70

Sandstone splitter
Phil Sakievich · · Unknown Hometown · Joined Aug 2014 · Points: 131

k I’ll weigh in.  IMHO the OP has made some pretty sweeping judgements about the quality of double axel cams off insufficient evidence. This single failure merits an investigation but not a conclusion. Especially such a sweeping, generalized one. If you want more evidence then you could go back up the route and try to recreate your failure by tossing a weighted pig onto the cam and document the placements before hand, and/or video them so they can be analyzed. If it’s really an issue with the structural design they should fail again or show evidence of the same failure mode post drop. The rest of this is pretty much pure speculation. We can he said she said all day long making estimates with one eye closed and our thumbs in the air, but it’s not a real investigation.

that guy named seb · · Britland · Joined Oct 2015 · Points: 236
grog m aka Greg McKee wrote:

Sandstone splitter

Tipped out cam pulverised rock causing it to umbrella.

patto · · Unknown Hometown · Joined Jul 2012 · Points: 25
Evan Mann wrote: If people want more techy climbing stuff to talk about here’s a single axle cam my friend also busted in Squamish.
grog m aka Greg McKee wrote:Sandstone splitter

Oh dear...  Apples and Oranges....

Cams without cam stops are not at all rated to hold ANY load in a fully open position.  In fact most will break at a fairly negligible, less than body weight load.  (Cams with cams stops are almost certainly also going to fail in the same placement, they just are much less likely to break.)

I can recognise that some people who are less engineeringly adept may struggle to see the distinction.  If you are one of those people then maybe try reading a bit more.  Or asking questions rather than making simlplistic statements like "So 9 pages later we can agree that finger sized cams somtimes break?".

Short of quality control issues (cough CCH).  Cams don't just "break".  Most broken cams are going to be from suboptimal placements.  Some design aspects will make cams more fragile to suboptimal placements.  The most obvious ones would be Omega Link cams.
Guideline #1: Don't be a jerk.

Climbing Gear Discussion
Post a Reply to "Structural Failure of Black Diamond Ultralight…"

Log In to Reply

Join the Community

Create your FREE account today!
Already have an account? Login to close this notice.

Get Started.