Structural Failure of Black Diamond Ultralight Camalot Size 0.4 Resulting in Injury
== Summary ==
A confidence inspiring placement of a Black Diamond Ultralight Camalot Size 0.4 failed in an unexpected situation resulting in an injury. Given the circumstances and preliminary conclusion, anyone using smaller size dual axle cams may want to reconsider what cams to include in their rack, or reconsider how this gear is placed. In particular, tighter yet not over cammed placements will make use of a thinner and therefore weaker part of the lobe on dual axle cams, since a hole is needed in the lobe in order to accommodate the opposite axle while pivoting. This weaker section of the lobe deformed in the scenario outlined here, reducing camming action, which is the likely reason for failure.
== The Scenario ==
A Black Diamond Ultralight Camalot Size 0.4 was placed in a granite crack with good rock on the climb “Neat and Cool” in Squamish, just before the first leftward traversing crux. The placement seemed very confidence inspiring to a leader experienced in placing gear and who has fallen on cams countless times. The placement was deep enough to allow for some amount of sliding and movement before catching, the crack wasn’t particularly flared, the rock seemed of good quality and is clean due to the popularity of the route, and the cam lobes were somewhat tightly compressed but not what one would normally consider a risk for getting stuck due to over-camming. The surrounding rock is notable for having slightly more texture and shape than “standard” Squamish granite, but the placement in the crack seemed to fit well. The orientation of the cam was slightly left, which oriented it more towards where the fall would initially start to catch due to the left traversing nature of the climb, but not in the directly downward direction where the greatest forces would likely be exerted. This orientation was picked mainly to ensure the placement fit well to the shape of the crack while still being reasonably oriented.
== The Fall ==
A few seconds before falling, the climber communicated to the belayer that the fall would likely occur, which allowed the belayer to be ready to give a slightly dynamic catch. The fall was an intentional release from about 1m above the placement with about 10m of rope out and insignificant rope drag. The fall initiated slightly left of the cam placement but without significant pendulum risk. Upon falling, the size 0.4 cam failed and shot into the shin of the falling climber, resulting in injury requiring medical attention including stitches. A size 1 Black Diamond Ultralight Camalot caught the fall, keeping the climber several meters off the ground.
== The Failed Cam ==
Inspection of the failed cam showed that one of the lobes was stuck in the closed position due to a deformation, which caused the lobe to catch on the opposite axle preventing it from opening up. The deformation of the lobe occurred where the lobe is thinner due to the hole needed to allow the opposite axle to slide through while pivoting.
This cam was nearly brand new, purchased 2 months prior, receiving very light use, having caught either 0 or 1 prior lead falls. The manufacturing code is 7054-2.
== Theory of Failure ==
The theory discussed among the experienced climbers that witnessed the event is that the cam failed due to the weaker part of the lobe compressing and deforming, resulting in loss of sufficient camming action. The slightly left orientation of the placement may have caused it to move somewhat while catching, which could have oriented the deformed lobe into a position in which it received a pressure point rather than more evenly distributed pressure, but this is pure speculation.
== Conclusion ==
Based on the theoretical mechanism of failure, it may be reasonable to consider avoiding placing smaller sized dual axle cams tightly such that the thin part of the lobe is in contact with the rock. This reduces the effective range of the cam and makes one consider if it’s perhaps sensible to not use smaller size dual axle cams at all, since this diminishes their main advantage of increased range compared to single axle cams.