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mmeyers

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Everything posted by mmeyers

  1. I wear a street size 9. My TC Pros are size 41, and I fit them for all day use and for my toes to be flat for more comfortable crack climbing. Not awesome for thin edging, but OK. size 40.5 would be better for edging, slightly less comfortable. IMO, based on your description, a size 42 for you would fit like my 41 does. They hardly stretch at all, but they did become more comfortable after a while. So, yes, more like a 'break in'. They will not stretch anything like a mythos or mocassym, not by a long shot.
  2. http://www.popsci.com/science/article/2013-06/super-hydrophobic-spray-makes-all-your-stuff-liquid-proof?src=SOC&dom=fb anybody see this yet? DWR? Matt
  3. Thanks. As an added note, I love it when someone proves my internet searching skillz inadequate, despite my best efforts
  4. Can anyone tell me if any of the bigger WA ski resorts (Snoq, Stevens, Crystal - although I'm mostly interested in the rules for Snoq) allow you to skin up and ski down, or do you have to take the lift up? (I'm looking for options for me during ski trips with the fam) Matt
  5. I'm sure some people do. As for me, I run to stay in shape for the mountains. When I run it's on hills or stairs or trails every time, so whatever pace I may or may not have is meaningless in comparison to what I think you're asking.
  6. if you haven't already, check wta.org here's a 5/4 report: http://www.wta.org/go-hiking/trip-reports/trip_report.2013-05-04.5073389181 if you're concerned about avy danger, you could shake your cobwebs off at Mailbox peak
  7. Something else to consider when hangboarding: hanging straight down with fully relaxed shoulders is not the best position for your shoulders. It seems more pronounced for me, but that position can act to put a prying force on your shoulder socket. I largely blame my prior hangboarding technique for my shoulder injuries. I ended up cutting my board in half and spreading them further apart, so my hands are not straight above my shoulders, and I keep my shoulders slightly tensed. Anyway, it's important to keep your arms and shoulders slightly tensed when doing that type of exercise repeatedly, especially weighted hangs. of course, ymmv. cheers!
  8. nice. I remember the first time I read about that climb. sounds like fun.
  9. it's like an "I Saw U" ad on the Stranger's Lovelab.
  10. aw, c'mon. anybody? I don't really want to solo.
  11. I've noticed this too, but I never knew it was isolated to the NW. For me, well, it's not for lack of wanting to project alpine routes, that's for sure. I'd rather be there.
  12. that's a good paper, imo. here are some more interesting ones as well: http://web.mit.edu/sp255/www/reference_vault/second_order_rope_fit.pdf http://www.caves.org/section/vertical/nh/51/Multi-point%20pre-equal%20anchors.pdf http://web.mit.edu/sp255/www/reference_vault/ITRS_02_force_eqn_analysis.pdf if you're into that sort of thing....
  13. we're headed straight into Nerdville! and BD2510 has it right. ('sup, I got my MS at RPI, too). so, let's play around with this: http://hyperphysics.phy-astr.gsu.edu/hbase/flobi.html if you put 100kg and 5m height, you'll get 4900J for impact energy. the impact *force* is calculated using the distance to stop, and you'll see how much it changes when you change the stopping distance. this is why rope stretch is so important, since this is the single largest component of elasticity (and hence stopping distance) in the system. the more the rope stretches (analogous to increasing the stopping distance), the lower the impact *force*. the elasticity in the system defines the impact force. but we all know that already. let's say your system can only stretch the equivalent of 1m (I'm simplifying a lot here, but that includes the rope, slings, the elasticity in the pro that's being loaded, your body, etc). the *average* impact force is 4.9kN. this is *average*, not peak. impact force looks like a bell curve with respect to time and distance. here is a highly simplified example: http://imageshack.us/photo/my-images/834/48273249.jpg/ as you can see, the average force (what's calculated above) will be *less* than the peak force. the less the system stretches, the higher the peak force is, and the higher the average force is. BTW, all of this crap is nonlinear. so, if your piece is rated at 5kN, it has probably blown, b/c the peak load is higher than the average of 4.9kN. so now what happens? well, we can make some simplifying assumptions (ie, make up some bullshit numbers) about the elasticity of the system. we'll assume linear elasticity (not realistic), and an impact profile similar to what is above (laziness mostly), and some other bullshit assumptions I've made, plus we know that the deceleration would occur in 0.2 sec (to reach 1m). we could then estimate that the peak force is 7.3kN (which is entirely dependent on the impact profile and my other made-up numbers). 5kN is reached in about 0.06s (again, entirely dependent on my assumed impact profile), or maybe about 0.3m (ditto), at which point your velocity has decreased to about 6.8m/s (ditto), which means you lose about 3m/s, and about half of your kinetic energy (ditto). see? it's all dependent on making up numbers (when you don't have real data to use), which is why no one wants to (or can) give anyone a specific answer, because even rules of thumb in dynamic systems are hard to come by. and that's why John Long's study is an interesting discussion starter, but not worth analyzing in detail, because in reality, gear is robust enough and over-engineered enough that it's pretty non-critical as long as you know what you're doing and you use a dynamic rope! so, to answer the questions directly, as well as I think I can: yes, gear blowing during a fall will reduce energy in the system, and therefore slow your fall. obviously, the more marginal it is, the less effect it will have. and an unequalized anchor of crappy pieces is better than no anchor at all, yes? yes to the first part (reduced properties), and no to the second (more force). I read somewhere that it takes a dynamic rope about 5-10 minutes to shrink back to its original length after a hard fall. so, the rope is viscoelastic, which in this case means that it takes measurable time for the rope to regain it's initial elasticity state. the time between blowing out one piece and hitting the next piece is small enough that the stretch will not rebound. the impact on the second piece will not be the *same* as the impact on the first piece, but that definitely does not mean that the force on the second piece will be higher than if the first piece did not exist. this is because, in typical situations (aha, more assumptions!) the rope will still retain a lot of it's elasticity (you're not going to max out the elasticity in one fall on one piece that rips out). hopefully I'm able to explain my thinking clearly here, and that I'm making sense.
  14. I'd say no, with one caveat. if the piece that pulls is complete crap (ie, a piece of scotch tape or something), then yes, pulling that piece will not reduce the fall energy by any significant degree. you'd basically have a 2-piece anchor with a bit extra slack in the system. however, duct tape is a different story. IMO, "momentary relaxing of tension" is meaningless. If you assume that the rope and slings are perfectly inelastic, then pulling a piece will still result in energy loss, and will reduce fall energy. the measure of his use of the word "significant" is proportional to the quality of the placement of the piece that fails. I expect tvashtarkatena to weigh in on this.
  15. I think he's talking about 3 pieces placed horizontally, and tied together, such that the middle arm is the shortest. assume an ideal knot, and ideal arm lengths. if we assume good equalization, then we can reasonably assume that the middle arm already has a higher load than the outer ones. if, under load, one of the outside pieces failed, then yes, the middle piece would take most of the load because it still has the shortest arm. where he's wrong is that the the 3rd arm would still carry some load, assuming elasticity in the arms, and it would be more than it was carrying when all 3 pieces were intact. the error in his logic is that he says the 3rd piece isn't carrying any load until the 2nd piece blows. if it was all "equalized", and the 3rd piece is not seeing any load, then the 1st piece would not see any load either, and therefore would not blow. all the load would be on the middle piece. what he's describing would happen if there were 3 totally unequalized pieces in series. I think.
  16. haha. a PhD in physics will mostly likely be able to explain to you the behavior of the wave function of particle colliding with your gear placement. no offense to any physics PhDs out there I have a masters in mechanical engineering, and I approve the basics of what Rad is saying. pulling gear transfers energy from kinetic (falling) to other forms (thermal, material deformation, noise, etc). lower kinetic energy means lower velocity.
  17. when I've been trying to move fast cleaning a traverse, I have had success balancing the aiders (and my weight) on each side of the piece, and then hopping and pulling the piece in one move. it can be a bit violent when the piece comes out and you swing a good bit, but it's fast.
  18. I was comfortable placing pro, until I started aiding and had a few brass offsets and small cams pull out on me I asked about the bolt ladder b/c it's a good way, IMO, to get your form down, and learn to top step (which is not necessary, per se, but makes it more efficient), and get the feel of the fifi sliding when you do so, and basically decide how you want to arrange your gear. that's what I did, but I'm sure lots of others here learned differently. I did some of that at the gym, and on the N side of the new location of the mountaineers building. if you're comfortable climbing a bolt ladder and have all of that stuff basically sorted (not dialed, just comfortable), then you just need to get a belay partner and get outside and get some practice. I don't think there's much more to it. city park is a good one, as is iron horse. another option is to climb godzilla, and set up a TR on city park, and then mock-aid. I've heard of people doing that, too.
  19. have you done any aid? ie, forget about protection, could you climb a bolt ladder? or are you looking to gain experience placing protection? Matt
  20. ascending a vertical/overhanging fixed rope without having to clean: frog system. doing lots of aid, cleaning lots of pitches, esp if there's any traversing to be done: 2 ascenders, 2 aiders short aid pitches, or low angle stuff: 1 ascender + aider, 1 progress capture device (grigri, minitraxion, ascender) on belay loop or chest sling (which is really just the frog system, slightly modified) Matt
  21. Anybody interested in getting some climbing in at WA Pass? I'm free 10/6-7. In Seattle, I have car and gear.
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