Gear failure (small cam)
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if a crack tapers ... use a nut ... |
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Surprised no one has mentioned Ball Nuts(z) yet. |
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Allen Corneau wrote:Surprised no one has mentioned Ball Nuts(z) yet. - Nearly a 2:1 expansion range - Smaller "head width" than micro cams - Stronger than the same size in micro cams (7-8kN) - Less expensive than cams (~$30-35 each)I love me some ballnuts. I have yet to fall on one and hope I really don't. The #1 is awfully slim. |
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bearbreeder wrote:if a crack tapers ... use a nut ... and itll take up less space for your fingerlockhaven't climbed at the gunks much eh? |
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Garret Nuzzo-Jones wrote: I love me some ballnuts. I have yet to fall on one and hope I really don't. The #1 is awfully slim.I've fallen on all of mine multiple times. They are incredible pieces when properly placed. The one thing that I have noticed is that they can be very difficult to remove after falling on them. |
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JSH wrote:If it umbrella'd out ... it had room to umbrella.Simple as that. It might have looked like a good placement, but it's not rubber. It didn't compress past a certain size and snap back after the cam inverted - it rolled through a placement. Perhaps it walked after he examined it, or his eye for "perfect" is imperfect. |
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This is only true if the rigid stem doesn't snap when it's loaded against the bottom of a pin scar. I've personally seen a C3 snap in a pin-scar where aliens hold perfectly. rgold wrote:Folks who doubt my comment ought to read the BD engineering account just above posted by John Peters. Although theoretical in nature when I made them, there seems to be confirmation from testing. I don't know if I can say it any better, but I think the BD comment about "needing torque" is a misleading. It is true that a more rigid stem creates torque, but it isn't the presence or absence of torque that affects the cam's resistance to extraction. In order to function, cams have to be loaded along the axis defined by an unbent stem. With a rigid stem sticking straight out from the cliff face, you get a vector component along the stem as the stem is forced down off the horizontal, a component which grows as the stem moves further down. This vector component, although small, is nonetheless the load that activates the cams. The other component, perpendicular to the stem, rotates the cams but doesn't do anything to engage them. What happens then depends on the internal configuration of the crack. If it tapers as it gets deeper, then the rotation could also compress the cams. But if the crack is uniform or flares as it gets deeper, then the load necessary to keep the piece in may not be present. If the crack tapers down very quickly or if it is shallow and the ability of the lower cams to pivot in is blocked, then the unit will pivot around the lower cams rather than around the upper cams, and, since the crack is shallow, this could force the upper cams entirely out of the crack. In this case, the increased torque from a rigid stem might be a disadvantage, although the entire situation presents nothing but bad outcomes: cams not loaded so as to engage and rotation popping upper cams out of the crack. (Note, by the way, that this could be a mechanism for perceived "umbrella'ing out" that doesn't involve some portion of the crack being too big for the cam expansion range.) With a flexible stem, you get little or no loading in the direction needed to force the cams against the rock walls, which is why such cams pulled under low loads in the BD tests. By the way, a tied-off rigid-stem cam in a horizontal crack is likely to be to be considerably stronger than a modern flexible-stem cam for analogous reasons. An interesting question is whether Totem cams would be subject to the drawbacks of flexibility mentioned above. The Totem system transmits loads directly to the cams in a way which, it seems, would still function even with the stem in a bad position. |
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Taken about 7 consecutive 10 footers onto an "okay" #1 TCU never moved at all. |
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Thought this was a pretty neat video. youtube.com/watch?v=iM6D8Kw… |
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Garret Nuzzo-Jones wrote: I love me some ballnuts. I have yet to fall on one and hope I really don't. The #1 is awfully slim.Shhh, that's my run-out piece |
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Garret Nuzzo-Jones wrote: I love me some ballnuts. I have yet to fall on one and hope I really don't. The #1 is awfully slim.I had a friend whip on a #1 ballnut that I placed. He took a 30' fall and weighs over 200lbs. It took a couple of really cold days before the ballnut finally came out. A good small cam placement relies on a near perfect fit. This means you need many different brands since one brand does not overlap well enough to be sufficient as the only small cams you carry. |
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I've been climbing with people lately that love the micros, and they use them often on 5.easy-5.easy-moderate climbs, something I don't understand. When I started climbing trad, I was told on the lower grade climbs there was no reason for small (micro) cams, and that they were hard to place. Of course, I carried the blue and green alien for a while anyway, because I was convinced having some gear was better than no gear. |
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J. Serpico wrote:I've been climbing with people lately that love the micros, and they use them often on 5.easy-5.easy-moderate climbs, something I don't understand. When I started climbing trad, I was told on the lower grade climbs there was no reason for small (micro) cams, and that they were hard to place. Of course, I carried the blue and green alien for a while anyway, because I was convinced having some gear was better than no gear. The yellow is borderline micro, not as finicky as green or blue, but still harder to gauge. If the crack isn't perfectly parralel, or better, if you can't find a bottle neck, it's probably worth rethinking the placement of that piece. Anyway, unless I need a rest, or I'm climbing on doubles, I rethought the whole any gear is better than no gear thing. Marginal gear just stresses the system and mental pro is great as long as you don't actually fall on it. The advice I was given was sound because if you have a green alien, you will find a spot to use a green alien, and unless you place it perfectly and attach a screamer, it might not be worth placing a marginal micro cam.A screamer on a green alien? Really? If you are halfway competent at placing gear you should be able to place finger/tips sized cams that will hold a fall. |
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Maybe, but there isn't much room for error on placement or quality of rock. |
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You really should change the title. Not that most of us didn't already know that this was going to be a case of user error. |
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While aiding on cams in sandstone I have ripped out more than I can remember sometimes two or three in one go.Some I could blame on the rock others seem to be in good hard wingate simular to Indian Creek. Personally I always feel much more comfortable with nuts more so wire stoppers. No one seems to mention the rope stretch theory that I have often thought about . When a fall occurs the rope stretches then retacts taking the shock away from the can for a split second and perhaps loosening it...then it is re-shocked ??. I have often wondered if this could affect the holding power of a cam placement this being regardless of the cam size.Perhaps the cam experts can refute this theory. |
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BrianKostelnik57 wrote:I place a lot of small cams. I'll admit, I'm trigger happy sometimes, but I recognize a good passive placement and opt for that when I can get it. It's important to remember to opt for the bigger size when the placement seems borderline. In other words, if the placement is between a green alien and a yellow alien, I opt for the yellow, even if it's up against the smallest margin of its range. Yep, it might walk and become difficult to clean, but that's my second's problem. He/she can hang on the rope or finagle a way to get it out. When it comes down to it I really don't care. I protect myself, and don't care if the gear is difficult to clean gear blows my follower's "send". Of course I don't go stuffing cams haphazardly into too-small placements and leaving booty everywhere, but I do make sure I'm protected and pay special attention to the size choice of smaller gear.Probably important to note that you wouldn't just cram gear in w/o thinking about it's removal if you are planning on moving efficiently in the mountains. Cragging at your limit, that's a different story ;-) |
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J. Serpico wrote:Maybe, but there isn't much room for error on placement or quality of rock. Before attacking people, very carefully go back and read what I wrote. I noted people climbing 5.easy shouldn't be placing these pieces. I also noted that beginning leaders shouldn't be. I didn't say nobody should. So yeah, if your not experienced or your about to shit your pants while placing a microcam, probably tossing a screamer on isn't going to be a bad idea.Not trying to attack you but I don't believe the intended purpose of screamers is "I don't know how to place gear, so I'm going to throw this on there and hope it helps". Also idk what you are calling 5.easy, but I can think of plenty of stuff under 5.10 that would be significantly more difficult / dangerous without a green alien sized cam. |
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Ryan Watts wrote: Not trying to attack you but I don't believe the intended purpose of screamers is "I don't know how to place gear, so I'm going to throw this on there and hope it helps". Also idk what you are calling 5.easy, but I can think of plenty of stuff under 5.10 that would be significantly more difficult / dangerous without a green alien sized cam.Yup. Go do Drunkard's Delight (easy 5.8) without a green alien and then tell me you don't need small gear below 5.10. In the end these things are all guidelines. If I can get in a good #2 Camalot, I'm going to use it instead of a blue alien. But sometimes that blue alien is all you can get. In which case you accept your margin of safety just went down sharply and you act with that in mind. |
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I think Ryan Williams summed my thoughts up. Basically he wrote what I wrote minus the screamer. Sorry adding a little extra margin makes people foam at the mouth. Again, if you read my post I was all about placing good gear, and gear you can verify is properly placed. I wasn't advocating being sloppy and making it all good with a screamer. But certainly a screamer on a micro cam isn't going to hurt. |