freeclimb9 Posted March 21, 2002 Posted March 21, 2002 I learned some valuable information from a recent lengthy thread on gear and webbing. Many of the posters --a consensus by some people's reckoning-- stated that nylon, or spectra, webbing over a wire rope (i.e. a cable) on a piece of protection would "cut like a hot knife through butter" if it sustained a fall. An "obviously stupid" combination. Couldn't hold a bag of rocks. Although no arguements of the importance of cable diameter (i.e. radius of curvature) in these claims were offered, or mention of the use of sacrificial webbing in sewn-gear designs was made, great anecdotal evidence was given: One case. I think that's a trend. Too bad there's not much empirical evidence, but the blanket statements from anonymous posters convinced me! My own paltry experiences and problem-solving abilities pale in comparison to the brilliant posters who've enlightened me. What an idiot I've been. I'm lucky to have lived so long because my rack has assorted examples of these booby traps. I should've been playing the lottery considering the odds I beat. I've now rethought some of the descriptive terms I'd used for these pieces (eg. stonker and bomber), and now suggest other names:crater fish dance death fersure And don't even think about girth hitching these things, or replacing the sewn sling with a tied sling or accessory cord: it reduces the strength of the webbing, or cord, by up to 30%. And a single sling over the cable is some kind of engineer's stupidity. I did find a quote from a one-time BS engineer, Chris Harmston: "Single loops cut on the wire of the Jr's. These loads range from 1500 to 2500 lbs. With the doubled loop the cable breaks at loads over 3000 lbs (rating is 12 kN = 2698 lbf.). We feel that the use of single loops is not sound advice. They are still strong enough for the vast majority of situations you could encounter. End BD recommendations. The following recommendation is my personal one and is not to be taken as recommendations by Black Diamond. I use single loops. I recognize the limitations of doing this. I know that these can fail at much lower loads. I never use these as the only piece of pro when there is the potential for a high fall factor. I use double loops so that the webbing can be extended. I also cover the wire with a 1/4" thick layer of fiberglass tape and athletic tape to help protect the web from the cable. Using tied slings is fine for many situations. I don't use them if I have a choice."But he's one crazy mo'fo with a death wish. Must be an academic type. Glad he doesn't climb in the PNW cause you guys would have to carry his mangled corpse away from a hideous --and, sadly, preventable-- fall. Girth hitch something, and you could, like, spontaneously combust, or something. And to think I've used the lethal girth hitch even on gear like .Must've been smokin crack (definitely not the BC chronic). Probably, with all the education I've had, my head is so full of facts, there's no room for thinking. Thanks to all for straightening me out. I'm gonna cut all that dangerous webbing off my gear and solely use carabiners to clip 'em.Got any comments, flame throwers? "Cuz the boyz in de hood are alwayz hard You come talkin' that trash we'll pull your card Knowin' nothin' in life but to be legit' Don't quote me boy, cuz I ain't sayin' shit ... --NWA Quote
Dru Posted March 21, 2002 Posted March 21, 2002 difference between a unpadded wire and padding and between sewn loop and girth hitch? or are you mad cause we all dont agree with you? if you and your partners are OK with it then go for it and dont make SAR come out to scrape up your splat when you splat. but i would not climb with someone who took less biners and then girth hitched slings straight thru a wire nut clip in point. although i would climb with a pot head like smoky mcpot, or with a guy who used a spectra cordelette...if they were cool. but not with no "legal speed" freek like you cause i can see you pitchin off when you get the shakes. Quote
Matt_Anderson Posted March 21, 2002 Posted March 21, 2002 Despite flaws in his argument, a well written and amusing diatribe. (I like sarcasm) [ 03-21-2002: Message edited by: Matt Anderson ] Quote
chucK Posted March 21, 2002 Posted March 21, 2002 I am wondering what is the flaw in the argument that compares slings through a wire with the slings through a metolius TCU? You guys can't possibly be thinking that that extra (.1mm thickness) colored tape is gonna make all the difference do you? Quote
lizard_brain Posted March 21, 2002 Posted March 21, 2002 If safety is a trend, then I'll be trendy. Quote
Dru Posted March 21, 2002 Posted March 21, 2002 quote: Originally posted by chucK: I am wondering what is the flaw in the argument that compares slings through a wire with the slings through a metolius TCU? You guys can't possibly be thinking that that extra (1mm thickness) colored tape is gonna make all the difference do you? Tape, no, but hard plastic, yup. 1mm thick on each side, on a 4mm wire, can make it 6mm diameter, or a 50% increase. But like I said, do the drop test experiments yourself, its a good way to waste a rainy day and check out the breaking strength of some of your gear. Quote
chucK Posted March 21, 2002 Posted March 21, 2002 Dude I don't know? We have to carefully budget our rainy days around here. Have you done it (your bag o' rocks 'speriment) yourself? If so, please present a report. Quote
Rodchester Posted March 21, 2002 Posted March 21, 2002 freeclimb9: I also find your mistatements amusing. You quoted "webbing over a wire rope (i.e. a cable) on a piece of protection would 'cut like a hot knife through butter ... '" If this claimed quote came from my post, I am calling bull shit on you. What I wrote was: "Is it a hot knife through butter? No...that is why I even said it can be done at times (in a pinch), but it GREATLY increases the risk." What part of "No" do you not understand? If you follow the general direction of the thread, it is apparent that what most of those opposed to your position were stating was that girth hitching directly to a wire cable is not a good idea. There was nothing stated or noted about cables coated in rubber and or plastic. Even when you implied it, (never actually just coming out and saying it) the general direction of thread stayed on point...that is cable...wire cable...not plastic coated cams and rubber coated nuts. Yopu wrote: "Although no arguements of the importance of cable diameter (i.e. radius of curvature) in these claims were offered" I guess my wording was not exact and maybe my calling it the rope bearing surface is not a term of art, but your assertion is nothing short of disengenous. I wrote: "Also most of your info as cited pertains to strengths, not rope bearing surface and or cutting ability? It doesn't matter how strong a rope or a draw is, it can still be cut. The smaller the rope bearing surface the greater the "cutting" effect on the rope or draw." Yet you never respond on point? Now you claim no one bought it up? Hmmm. My statement clearly put you on notice and implied a request for a response addressing the issue. Why didn't you just come out and clearly state that as with most "rules" there are exceptions. Point out the exceptions and everyone would have said, "oh good point." But I guess you still say this young Jedi should girth hitch wire cable whether it is encased or not. I agree the personal attacks are not proper. But bull shit is bull shit. Quote
cj001f Posted March 21, 2002 Posted March 21, 2002 quote: Originally posted by chucK: Dude! I think that is his point. The part about "quite a bit of practical measurements" that is. There are tons of posters who posted that it is obviously stupid to girth hitch a wire but it is doubtful that many have done any practical measurements. I have not. If anybody else has, they have not posted their findings. Dru is the only one so far, but I didn't see anything yet that talked about girth hitches through wires? AFAICT Dru's experiments blew out a copperhead. [ 03-21-2002: Message edited by: chucK ] I was responding to his quote of:"I did find a quote from a one-time BS engineer, Chris Harmston:"As last I checked Chris had a MS, this was either an insult, or a mistake. From what I've seen - Chris is one of the few sources of reputable, at least quasi-scientific experiments. Russ Walling being another. Going against popular opinion is all well and good. You need data to go against popular opinion and be accpeted. Freeclimb has no data, no analysis - and nothing to back his opinion up besides spray. Merely questioning the validity of peoples analysises does nothing to establish the validity of his own. Carl Quote
chucK Posted March 21, 2002 Posted March 21, 2002 Well one of us is mixed up then, because I thought he was using Chris Harmston's quote to further his argument. I think the "BS engineer" was a sarcastic response to Retro's dig on engineers. Quote
JoeTool Posted March 21, 2002 Posted March 21, 2002 Ok; If you take a 186 lb chunk of railroad track and hoist it 75 ft. up a tree and at about 50 ft up you anchor a old chounaird #8 stopper and too that you girth hitch a 24 in 1/2 in new dry nylon runner tied with a water knot with 4 in tails, and to that you clip an old chouinard oval, and you secure the 11mm dynamic rope (retired) to the base of the tree, and you drop the railroad tie,you get... a BIG PIECE OF STEEL EMBEDDED IN THE GROUND, AND A RUNNER THAT SNAPPED,YOU GUESSED IT, AT THE GIRTH HITCH! its not "scientifical", its REAL world!!! Quote
Nelly Posted March 21, 2002 Posted March 21, 2002 FreeClimb9 - Check out this site! A group of MIT PhD's have, indeed, performed a lot of drop testing. In fact, you can send inquireys via e-mail and they will test a system for you, time and money permitting. http://www.marlboro.edu/~mahoney/DropTest/DropProposal.html I still advise against using the girth hitch on a nut or sling unless it was my only option. Quote
imorris Posted March 21, 2002 Posted March 21, 2002 We have a drop test facility to evaluate various components of our anchor systems. I may be able to fit in such an experiment when we do our next suite of tests. Link: CMRU Drop Tests -Iain [ 03-21-2002: Message edited by: imorris ] Quote
Dru Posted March 21, 2002 Posted March 21, 2002 quote: Originally posted by Nelly: FreeClimb9 - Check out this site! A group of MIT PhD's have, indeed, performed a lot of drop testing. In fact, you can send inquireys via e-mail and they will test a system for you, time and money permitting. http://www.marlboro.edu/~mahoney/DropTest/DropProposal.html I still advise against using the girth hitch on a nut or sling unless it was my only option. Things they could droptest. A watermelon. Dick Cheney Dick cilley A hippopotamus. Blotter Quote
freeclimb9 Posted March 21, 2002 Author Posted March 21, 2002 flame on! BTW, Harmston (used to work for Black Diamond) has done testing on single strips of nylon webbing over the cables they use for MicroCamalots. They broke at strengths all over the place (down as low as 1,000lbs but mostly from 1,500 to 2,500), and no standard deviation was given. No testing was done with spectra. Bluewater did similar tests back in the 80's when they started selling sewn spectra. They break (cut, more accurately) at over a ton and a half. I've personally caught a fall of factor 1 (about a 25' fall) where the piece was a #4 metolius TCU slung over the wire with 5mm spectra cord tied with a double fisherman's knot. It distorted the shit out the the wire, but no harm was noticeable on the cord. That's one example. The girth-hitch testing done suggests that their breaking strength is comparable to that of tied webbing. So a section of girth-hitched cord might not break either.There are no tests of webbing girth-hitched over wires that I know of. I think it's possible that they'd break at a higher strength than single webbing since the area of contact between the sling and wire is greater. Speculation. Does this help anyone? Probably not. Obstinate crowd, maybe. Throw some bags of rocks. Get out the funkness device. But don't claim absolutes. And don't assume that I don't know the strength limitations of the gear I use especially when I offer empirical support. Or just stick to the roadside Quote
erik Posted March 21, 2002 Posted March 21, 2002 i think freeclimb eluded to the real issue when he was suggesting the use of stimulants.... carry on boyz and gurlz Quote
erik Posted March 21, 2002 Posted March 21, 2002 here is couple other dangerous setups i wouldnt want to use Quote
imorris Posted March 21, 2002 Posted March 21, 2002 quote: Originally posted by erik: here is couple other dangerous setups i wouldnt want to use Quote
freeclimb9 Posted March 21, 2002 Author Posted March 21, 2002 My horoscope for today (Leo)"The new Aries Sun burns away the last of your inhibitions. Leo has the strength to turn the tide single-handedly, if necessary. Leadership fills a void instead of just inflating another ego. Others will thank you for this." I'm thinking this full-strength Idaho beer I'm drinking to celebrate Spring is some dope shit. And it's over 40 outside right now. This hasn't happened in weeks. I have to admit that the beer yesterday might have got on top of me. Who cares when you're having fun? Where's the tequila? Damn, the ice is melting fast. But the alpine routes will be getting in shape after mud-month.later Quote
Dru Posted March 22, 2002 Posted March 22, 2002 quote: Originally posted by freeclimb9: I'm thinking this full-strength Idaho beer I'm drinking Utah must suck, dude. Quote
freeclimb9 Posted March 22, 2002 Author Posted March 22, 2002 quote: Originally posted by Dru: Utah must suck, dude. You have no idea. If it weren't for the outdoor recreation opportunities, there'd be wall to wall fuck all. Quote
Dru Posted March 22, 2002 Posted March 22, 2002 quote: Originally posted by chucK: Dude I don't know? We have to carefully budget our rainy days around here. Have you done it (your bag o' rocks 'speriment) yourself? If so, please present a report. I did a similar test with some copperheads a few years ago finding out how much force it took to blow em out. woo hoo! basically it took a 40L pack full of rocks, taking a factor-1, from about 20 feet, on a #4 alumahead.. i dunno what exactly that was in kN. Quote
chucK Posted March 22, 2002 Posted March 22, 2002 quote: Originally posted by Dru: I did a similar test with some copperheads a few years ago finding out how much force it took to blow em out. woo hoo! basically it took a 40L pack full of rocks, taking a factor-1, from about 20 feet, on a #4 alumahead.. Static or dynamic rope? I'm sure there's a geek or two on rec.climbing who would convert it to KN for you. Quote
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