The Master Cam Issue

July 9th, 2009 - Metolius Climbing wrote:

It is our understanding that this forum is intended to be a venue for discussion by individual climbers. We feel it is generally inappropriate for us as a manufacturer to participate. Manufacturers, retailers, organizations (such as AAC), and guides are all great resources that can be contacted directly. When you contact us with a question about our gear, we will work with you one on one to provide answers. However, the moderator asked us to comment on this thread, so we are making an exception. To contact us directly, go to metoliusclimbing.com. You can call to talk to a live body, or send in a letter, and we will respond as soon as we can.

We would like to start by thanking everyone that contributed to this discussion. One of our main goals has always been to get climbers to look critically at all the gear they use. Every piece of gear has design limitations. Every piece of gear is subject to misuse, and every piece of gear can fail well below its rated strength. It is critical to personally analyze and inspect every piece of gear you use and understand its limitations. You cannot leave this up to someone else.

The ideal cam would have a trigger that would disappear after placement, to avoid accidental triggering of the cam lobes. While this is not possible, we feel we have used the best option for a flexible body, single stem cam.

When we first saw the images of our cam moving in the fixture during the horizontal test, we suspected there could be a problem with the test. We do horizontal pull testing as one of our standard tests, and have never seen this problem. However, we immediately attempted to duplicate the result we had seen in the video. We were unable to get the cam lobe to retract as it appeared to do in the video. Then we began looking more closely at the video, and noticed that the fixture was moving. We contacted the tester and informed them of the fixture problem. The tester agreed with us and created a new fixture that would not move. With the new solid test fixture, the tester was unable to duplicate the initial negative result. No problem, Mystery solved.

We would like to encourage the tester to keep testing, keep busting gear, and keep posting, but be a little more prudent about getting confirmation from another tester prior to releasing results. One positive thing these tests indicate is that cams don’t seem to work very well in expanding cracks. We will try to duplicate this expanding crack test, something we have never been able to do before.

There is also an image of a person holding a Master Cam head in one hand and bending the stem 180 degrees in an effort to demonstrate the trigger pulling on the cam lobes. We have been unable to reproduce this effect in any placement in the field. The tester was also unable to produce this effect in the horizontal test set up. The key to performing this trick is that the cam lobes have to be fully extended so there is no slack in the trigger cords. In any viable placement, the cam lobes must be in some degree of retraction, which creates slack in the trigger cords, which makes it all but impossible for them to pull on the cam lobes. We specifically chose a Kevlar core, nylon sheath trigger cord because it does such a good job of isolating the trigger mechanism, and allowing independent movement of each cam lobe.

I mentioned earlier that we do a horizontal placement test as one of our standard tests. This is not a standard UIAA test, but we plan to present it for discussion and consideration at the next UIAA safety committee meeting.

I would also like to mention that we do an off angle test, to try to evaluate a cams performance in a bottoming crack. In this test the cam is plugged straight into a crack fixture, and blocked from rotating and aligning itself with the direction of pull. The initial test results indicate that the cams performance becomes very unpredictable when loaded like this. We will continue to refine this test in hopes of getting a more consistent result, but preliminary results indicate that this should only be a placement of last resort, and should not be expected to hold a serious fall.

Thanks to all who have participated in this discussion, and thanks to the moderator for inviting us to contribute.

Doug Phillips

President Metolius Climbing