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majid_sabet
Feb 13, 2008, 7:41 PM
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1-You and your partner found a 50 feet rock to do some face climbing but the desired anchor was few feet away from the edge however, you noticed a closer natural anchor (tree) near the edge but questionable . You decided to use the tree as a redirect since it was closer to where you wanted to climb and then you setup your main anchor in the back some distance away. Based on how you rig this TR, if your main anchor is rated to 18 KN, how strong your redirect anchor should be ? A-Less than 18 KN B-18 KN plus an additional (40%+) but no more than 36 KN C- up to 2X of the original belay anchor D-18 KN plus an additional 10 % = 19.8 KN E-Same as main anchor or 18 KN [URL=http://imageshack.us] 2- Your partner was up 10 feet when he lost his footing and since you did not do your TR redirect calculation correctly, the whole redirect was gone. Based on what you knew a typical dynamic 10.5 mm rope and since you had 90 feet of rope in service before your belay device cached, Your TR rope is going be stretched to; A- No more than 2 additional feet B- An additional 20% - 40% rope stretch C- An additional 60% rope stretch D- 90 feet plus an additional 2.5 % rope stretch E- Partner may hit the ground [URL=http://imageshack.us]
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glytch
Feb 13, 2008, 7:56 PM
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... question 1 is meaningless without angles. Also, sort of meaningless in general... question 2 also meaningless without specific dimensions. Majid, man, this isn't your day.
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onceahardman
Feb 13, 2008, 7:58 PM
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In picture #2, the combined weight of the tree+ climber, dragged across the edge of the cliff, will saw through the rope, dropping the climber to the ground, where (Wile E Coyote-like), he will then be struck by the falling tree!
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majid_sabet
Feb 13, 2008, 8:05 PM
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glytch wrote: ... question 1 is meaningless without angles. Also, sort of meaningless in general... question 2 also meaningless without specific dimensions. Majid, man, this isn't your day. Every thing is right there may be you should respond after your PMS is over
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glytch
Feb 13, 2008, 8:12 PM
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majid_sabet wrote: glytch wrote: ... question 1 is meaningless without angles. Also, sort of meaningless in general... question 2 also meaningless without specific dimensions. Majid, man, this isn't your day. Every thing is right there may be you should respond after your PMS is over aww shucks. Well, let's make a deal: I promise I won't comment on your asinine threads if you learn high school physics and middle school trigonometry. Deal?
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tuna
Feb 13, 2008, 8:25 PM
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This is really fucking stupid. The whole setup is fucking stupid OR MAYBE THAT IS THE POINT. ciao Santana
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theShiba
Feb 13, 2008, 10:13 PM
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How is the tree the "redirect" anchor? If you know anything about physics, the greater percentage of load is on the tree, as pictured. As for #2... does it really matter when there is a tree falling on top of you?
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majid_sabet
Feb 13, 2008, 10:43 PM
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theShiba wrote: How is the tree the "redirect" anchor? If you know anything about physics, the greater percentage of load is on the tree, as pictured. As for #2... does it really matter when there is a tree falling on top of you? No tree is not falling on you, you just lost your redirect anchor( broken webbing, biner, tree, etc). Also, may you want to teach some basic physics to glytch
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theShiba
Feb 13, 2008, 10:52 PM
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No, I get it... the problem is: the. tree. broke. Now it's falling. Down. Onto the climber. Look at the picture. Maybe the rope will act as a pendulum and swing the climber out of the way of the falling tree... I honestly don't know why I am keeping this going. I guess I am just getting sick of these asinine TR tests that make absolutely no sense whatsoever.
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majid_sabet
Feb 14, 2008, 1:34 AM
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theShiba wrote: No, I get it... the problem is: the. tree. broke. Now it's falling. Down. Onto the climber. Look at the picture. Maybe the rope will act as a pendulum and swing the climber out of the way of the falling tree... I honestly don't know why I am keeping this going. I guess I am just getting sick of these asinine TR tests that make absolutely no sense whatsoever. Ok, since you are bored I will give your TR final exam right now; Assuming you find a solid tree and I give 30 feet of webbing, one biner and a 60 meter rope and I ask you to setup the strongest and the safest anchor with minimum failure for a straight 50 meter long rappel. How do you rig your anchor?
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tolman_paul
Feb 14, 2008, 1:37 AM
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Tie the rope to the tree, assuming no ginsu edge for the rope to run over.
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majid_sabet
Feb 14, 2008, 1:40 AM
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tolman_paul wrote: Tie the rope to the tree, assuming no ginsu edge for the rope to run over. how do you tie it ?
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skinnyclimber
Feb 14, 2008, 1:47 AM
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Answer to question 1. Place gear in a crack, place a bolt (if local ethics allow) or climb somewhere else. Answer to question 2. The gear / bolt you placed as a redirect doesn't fail and you are fine. Or you climbed somewhere else and you are fine.
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theShiba
Feb 14, 2008, 2:30 AM
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Underhand monkeyfist.
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no_email_entered
Feb 14, 2008, 3:10 AM
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did you give up on TR test part III? I still didnt get where the top ropeing was taking place. i really like this one tho.
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hugepedro
Feb 14, 2008, 4:50 AM
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The answer to question 1 is F - none of the above, because as long as your "main anchor" and your "redirect anchor" are each good for, oh I don't know, let's say 10kn, you'll be plenty safe, because ain't no way a tope rope fall will generate that much force.
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itstoearly
Feb 14, 2008, 9:47 PM
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Question 1: Rope breaks from rubbing that nice sharp edge. Question 2: The tree is about to kill your climber, so how far he falls is irrelevant.
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tuna
Feb 14, 2008, 10:49 PM
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How about who gives a damn about your stupid test. Just walk off the top of the choss pile. ciao Santana
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drector
Feb 15, 2008, 12:05 AM
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majid_sabet wrote: few feet away from edge Is this 30 feet or three feet? What does "few" mean here? Not that it matters but the question looks ill-conceived without sticking in real numbers even if they don't matter in the end.
majid_sabet wrote: ...in the back some distance away... Do you mean directly in line with the climb and 3000 feet behind the tree or at a 90 degree angle (rope redirection) but six inches from the tree? Again, the question looks pretty lame without this information. It makes it look like you are not competent even if the numbers don't affect the answer.
majid_sabet wrote: A-Less than 18 KN Why would anyone ever say that an anchor SHOULD be less than any specific value. That's just stupid. Also, zero is less than that and zero is not really acceptable, is it?
majid_sabet wrote: B-18 KN plus an additional (40%+) but no more than 36 KN Completely unnecessary for a TR anchor.
majid_sabet wrote: C- up to 2X of the original belay anchor What the hell does "up to" mean? 0.00001kn qualifies as being "up to" 2x of the original belay anchor. This is a gibberish answer without giving both ends of the range. Or maybe zero, as the assumed lower end of an "up to" range is what you meant like in the "lower than 18kn..." answer. That's pretty dumb. BTW, I'd like to mail you up to 2 million dollars. What is your address.
majid_sabet wrote: D-18 KN plus an additional 10 % = 19.8 KN At least this is a reasonable choice since it's not a range from zero to 2000000kn or anything dumb like that. Still, This is getting tiring.
majid_sabet wrote: E-Same as main anchor or 18 KN Ah. Less gibberish. My guesses are: 1. If the rock is close to the tree and when the tree falls off the cliff such that the climber will get dropped less than 1 foot from the event, the tree is pointless as part of the anchor. or 2. If the rock is far enough from the tree that when the tree falls, the climber hits the ground regardless of where he/she is on the climb then the tree needs to BE the anchor and the rock is useless. It must hold the full force and the anchor must be appropriate for any TR situation. Of course if this is the real question then the force the tree must hold will be more than the rock must hold based on the angle of the rope through the tree anchor carabiners. So what is that angle? or 3. If the rock is far enough to the side but close enough to the tree that the climber won't hit the ground when the tree fails but will swing to the side and hit the death-sticks that protrude from the side of the climb then the tree again must be the anchor and the rock is pointless. or 4. If the rock is lined up with the tree and the climber then what is the tree use for again? Maybe keeping the rope from rubbing on the edge of the cliff then it needs to hold some reasonable TR fall. If the edge is sharp then we're back to the tree needing to hold the full force and the rock is no longer useful again. On the other hand, another possible answer is that this is a deep-water free-solo type of climb and as long as the tree won't hit the climber, the anchors are not necessary. The climber simply falls into the water then swims to shore at which point eh tree falls on him there. Dave
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majid_sabet
Feb 15, 2008, 1:59 AM
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drector wrote: majid_sabet wrote: few feet away from edge Is this 30 feet or three feet? What does "few" mean here? Not that it matters but the question looks ill-conceived without sticking in real numbers even if they don't matter in the end. majid_sabet wrote: ...in the back some distance away... Do you mean directly in line with the climb and 3000 feet behind the tree or at a 90 degree angle (rope redirection) but six inches from the tree? Again, the question looks pretty lame without this information. It makes it look like you are not competent even if the numbers don't affect the answer. majid_sabet wrote: A-Less than 18 KN Why would anyone ever say that an anchor SHOULD be less than any specific value. That's just stupid. Also, zero is less than that and zero is not really acceptable, is it? majid_sabet wrote: B-18 KN plus an additional (40%+) but no more than 36 KN Completely unnecessary for a TR anchor. majid_sabet wrote: C- up to 2X of the original belay anchor What the hell does "up to" mean? 0.00001kn qualifies as being "up to" 2x of the original belay anchor. This is a gibberish answer without giving both ends of the range. Or maybe zero, as the assumed lower end of an "up to" range is what you meant like in the "lower than 18kn..." answer. That's pretty dumb. BTW, I'd like to mail you up to 2 million dollars. What is your address. majid_sabet wrote: D-18 KN plus an additional 10 % = 19.8 KN At least this is a reasonable choice since it's not a range from zero to 2000000kn or anything dumb like that. Still, This is getting tiring. majid_sabet wrote: E-Same as main anchor or 18 KN Ah. Less gibberish. My guesses are: 1. If the rock is close to the tree and when the tree falls off the cliff such that the climber will get dropped less than 1 foot from the event, the tree is pointless as part of the anchor. or 2. If the rock is far enough from the tree that when the tree falls, the climber hits the ground regardless of where he/she is on the climb then the tree needs to BE the anchor and the rock is useless. It must hold the full force and the anchor must be appropriate for any TR situation. Of course if this is the real question then the force the tree must hold will be more than the rock must hold based on the angle of the rope through the tree anchor carabiners. So what is that angle? or 3. If the rock is far enough to the side but close enough to the tree that the climber won't hit the ground when the tree fails but will swing to the side and hit the death-sticks that protrude from the side of the climb then the tree again must be the anchor and the rock is pointless. or 4. If the rock is lined up with the tree and the climber then what is the tree use for again? Maybe keeping the rope from rubbing on the edge of the cliff then it needs to hold some reasonable TR fall. If the edge is sharp then we're back to the tree needing to hold the full force and the rock is no longer useful again. On the other hand, another possible answer is that this is a deep-water free-solo type of climb and as long as the tree won't hit the climber, the anchors are not necessary. The climber simply falls into the water then swims to shore at which point eh tree falls on him there. Dave Dave You confused yourself. At 9 KN the tree starts to see some action . This is due to MA created by redirect. at 18Kn one of those anchor will pop cause the main in rated at 18. For redirect to survive and not to fail before main anchor, it must take min of 2X of the main anchor. At 90 degree angle (what you see out there) it could see additional 40% + extra forces . Next; when you have 90 feet of rope in service (as I was shown) and you are 10 feet up and loose your redirect, you are guaranteed up to 40% extra stretch in your rope length. At 10% rope stretch (9+ feet drop) your partner will deck not counting amount of pendulum to one side. When you have 40 feet of rope distance to redirect and another 50 feet of rope to climber, hitting the ground is guaranteed 100% even without a rope stretch with such pendulum .
(This post was edited by majid_sabet on Feb 15, 2008, 2:01 AM)
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yokese
Feb 15, 2008, 2:36 AM
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If I were a mod I'd consider to move all this bull$hit of "TR tests" from the beginners forums before someone takes them seriously. Unfortunately this self-appointed "rope master" can create quite a bit of confusion. With 90º angle you get 40%+ forces?? Check your basic trigonometry: F_anchor = 2xFxcos(45) = 1.05xF --> an extra 5%, not 40% (and that would be without friction in the biner) Stretch of 40%?? That's a bungee, not a climbing rope. Top ropes generating 18kN??? Please....
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tuna
Feb 15, 2008, 2:51 AM
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yokese wrote: If I were a mod I'd consider to move all this bull$hit of "TR tests" from the beginners forums before someone takes them seriously. Unfortunately this self-appointed "rope master" can create quite a bit of confusion. Yes you hit the nail on the head about the idiot being a self-appointed rope master. ciao Santana
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Drjellyfinger
Feb 15, 2008, 3:44 AM
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tuna wrote: yokese wrote: If I were a mod I'd consider to move all this bull$hit of "TR tests" from the beginners forums before someone takes them seriously. Unfortunately this self-appointed "rope master" can create quite a bit of confusion. Yes you hit the nail on the head about the idiot being a self-appointed rope master. ciao Santana You aren't kidding tuna! it's clear that if you tied a full douche bag (or the poster) to the climber in the CARTOON, the whole system would fail.......
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majid_sabet
Feb 15, 2008, 4:56 AM
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yokese wrote: If I were a mod I'd consider to move all this bull$hit of "TR tests" from the beginners forums before someone takes them seriously. Unfortunately this self-appointed "rope master" can create quite a bit of confusion. With 90º angle you get 40%+ forces?? Check your basic trigonometry: F_anchor = 2xFxcos(45) = 1.05xF --> an extra 5%, not 40% (and that would be without friction in the biner) Stretch of 40%?? That's a bungee, not a climbing rope. Top ropes generating 18kN??? Please.... three anchors, same forces applied as load = 10kn.how much forces each redirect anchor will see ? get on it [url=http://www.freeimagehosting.net/]
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majid_sabet
Feb 15, 2008, 5:13 AM
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yokese wrote: If I were a mod I'd consider to move all this bull$hit of "TR tests" from the beginners forums before someone takes them seriously. Unfortunately this self-appointed "rope master" can create quite a bit of confusion. With 90º angle you get 40%+ forces?? Check your basic trigonometry: F_anchor = 2xFxcos(45) = 1.05xF --> an extra 5%, not 40% (and that would be without friction in the biner) Stretch of 40%?? That's a bungee, not a climbing rope. Top ropes generating 18kN??? Please.... most dynamic rope elongations are between 30 to 38% and yes they act like a bongee cord. GOT IT? http://mtntools.com/...e/03DynamicRope.html
(This post was edited by majid_sabet on Feb 15, 2008, 7:25 AM)
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yokese
Feb 15, 2008, 7:28 AM
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majid_sabet wrote: note; most dynamic rope elongations are between 30 to 38% and yes they act like a bongee cord. GOT IT? Majid, you're wrong yet one more time (seriously, don't you get tired? because I certainly do) Those dynamic elongations are measured after a 1.77 factor fall, not in a top-rope. By the way, to pass the test they cannot stretch more than 40%. Therefore, the "guaranteed up to 40% extra stretch" that you mentioned some posts above is, as usual, just another demonstration of your deep ignorance. Edited to fix the quoting mess...
(This post was edited by yokese on Feb 15, 2008, 6:09 PM)
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theShiba
Feb 15, 2008, 9:41 AM
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1st tree 100% of the load. 2nd tree 100% of the load 3rd tree 52% of the load.
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majid_sabet
Feb 15, 2008, 6:03 PM
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yokese wrote: majid_sabet wrote: yokese wrote: note; most dynamic rope elongations are between 30 to 38% and yes they act like a bongee cord. GOT IT? Majid, you're wrong yet one more time (seriously, don't you get tired? because I certainly do) Those dynamic elongations are measured after a 1.77 factor fall, not in a top-rope. By the way, to pass the test they cannot stretch more than 40%. Therefore, the "guaranteed up to 40% extra stretch" that you mentioned some posts above is, as usual, just another demonstration of your deep ignorance. I did not specify what the FF was or how much FF will creates during a top rope and you started coming with bunch of #a and nonsense. Be a man and accept that you did not know how much the dynamic elongation were till now and They do act like a bongee cord.
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majid_sabet
Feb 15, 2008, 6:12 PM
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theShiba wrote: 1st tree 100% of the load. 2nd tree 100% of the load 3rd tree 52% of the load. How much does the first anchor (red color) gets ? 100% of the load which is 12 KN ? is this right ?
(This post was edited by majid_sabet on Feb 15, 2008, 6:13 PM)
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skinnyclimber
Feb 15, 2008, 6:13 PM
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majid_sabet wrote: yokese wrote: If I were a mod I'd consider to move all this bull$hit of "TR tests" from the beginners forums before someone takes them seriously. Unfortunately this self-appointed "rope master" can create quite a bit of confusion. With 90º angle you get 40%+ forces?? Check your basic trigonometry: F_anchor = 2xFxcos(45) = 1.05xF --> an extra 5%, not 40% (and that would be without friction in the biner) Stretch of 40%?? That's a bungee, not a climbing rope. Top ropes generating 18kN??? Please.... most dynamic rope elongations are between 30 to 38% and yes they act like a bongee cord. GOT IT? http://mtntools.com/...e/03DynamicRope.html Most dynamic cords have an elongation of something like 30% to 40% ON THE FIRST FACTOR 1.78 FALL according to UIAA testing. Idiot.
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theShiba
Feb 15, 2008, 6:32 PM
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majid_sabet wrote: theShiba wrote: 1st tree 100% of the load. 2nd tree 100% of the load 3rd tree 52% of the load. How much does the first anchor (red color) gets ? 100% of the load which is 12 KN ? is this right ? The way you drew it, yes. I don't care what the load is. I am giving you the %age of load on the anchor based on the angle of the rope attached to the anchor. For an angle ≤90º, the load on the anchor is 100%. When the angle is >90º there is a reduction factor of the load on the anchor point, as some force is redirected to another point. I approximated the angle you drew to mean that there would be about 52% of the force on that anchor, about 130º.
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onceahardman
Feb 15, 2008, 7:30 PM
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In reply to: I did not specify what the FF was or how much FF will creates during a top rope and you started coming with bunch of #a and nonsense Actually you did...by bringing up "dynamic elongation" def: Dynamic elongation is measured on the first fall of the standard UIAA fall test. Simply put, it is a measure of how much stretch will occur during a 1.78 fall-factor drop — an extreme indicator of how much a rope will stretch during a normal fall. Odds of a 1.78 ff on a top rope? =0 therefore, 40%=nonsense in this context. static elongation is a MUCH truer picture of expected rope stretch for a top-rope fall. Even if the belayer stopped taking in rope halfway up the route, while the climber continued climbing...for a 100 foot route, you'd have a 50 foot fall on 50 feet of rope=ff1
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majid_sabet
Feb 15, 2008, 7:38 PM
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theShiba wrote: majid_sabet wrote: theShiba wrote: 1st tree 100% of the load. 2nd tree 100% of the load 3rd tree 52% of the load. How much does the first anchor (red color) gets ? 100% of the load which is 12 KN ? is this right ? The way you drew it, yes. I don't care what the load is. I am giving you the %age of load on the anchor based on the angle of the rope attached to the anchor. For an angle ≤90º, the load on the anchor is 100%. When the angle is >90º there is a reduction factor of the load on the anchor point, as some force is redirected to another point. I approximated the angle you drew to mean that there would be about 52% of the force on that anchor, about 130º. Well,The anchor with red rope (redirect) does not get 100% but sees 200% or twice as much. This is for the fact that you have load on one end and another load on the opposite side or the other end of the rope.if you build your redirect to handel 12 KN, it will fail cause at 6 KN load, it is already receives 12 KN or twice as much.
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hugepedro
Feb 15, 2008, 7:54 PM
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majid_sabet wrote: Well,The anchor with red rope (redirect) does not get 100% but sees 200% or twice as much. This is for the fact that you have load on one end and another load on the opposite side or the other end of the rope. Wrong. It will take 1.66 times the force on the climber. In your theoretical example that would be 16.6kn.
majid_sabet wrote: if you build your redirect to handel 12 KN, it will fail cause at 6 KN load, it is already receives 12 KN or twice as much. Wrong again. If it can handle 12kn it will never fail because there is no way a top rope fall will generate forces that high. So the point of this thread is . . . what?
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skinnyclimber
Feb 15, 2008, 8:32 PM
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hugepedro wrote: So the point of this thread is . . . what? To waste our Time... oh yeah, and confuse beginners.
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hugepedro
Feb 15, 2008, 9:24 PM
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skinnyclimber wrote: hugepedro wrote: So the point of this thread is . . . what? To waste our Time... oh yeah, and confuse beginners. Gotcha. So it's just another normal rc.com thread then, eh?
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drfelatio
Feb 15, 2008, 9:27 PM
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skinnyclimber wrote: hugepedro wrote: So the point of this thread is . . . what? To waste our Time... oh yeah, and confuse beginners. And to stroke Majid's ego.
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glytch
Feb 15, 2008, 9:55 PM
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yokese wrote: If I were a mod I'd consider to move all this bull$hit of "TR tests" from the beginners forums before someone takes them seriously. Unfortunately this self-appointed "rope master" can create quite a bit of confusion. With 90º angle you get 40%+ forces?? Check your basic trigonometry: F_anchor = 2xFxcos(45) = 1.05xF --> an extra 5%, not 40% (and that would be without friction in the biner) Stretch of 40%?? That's a bungee, not a climbing rope. Top ropes generating 18kN??? Please.... While I agree with your general sentiments re: majid, something's awry with your math on the forces generated by redirects. Using your math, cos(45) = sqrt(2)/2, so 2*F*sqrt(2)/2 = sqrt(2)*F ~= 1.4*F Other than that, though, right on. This thread borders on silly.
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glytch
Feb 15, 2008, 9:57 PM
Post #39 of 42
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Registered: Aug 29, 2006
Posts: 194
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Dave, Thanks for more clearly explaining why the original question is a) not meaningful without extra data and b) silly even with extra data. I think our resident questioner was trying to get at the issues with a redirect, but his example which includes the edge of a cliff and a (very!) underspecified problem statement is not really helpful towards that end. I'm glad I'm not the only one that noticed the utter lack of meaning in the question as put. G
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majid_sabet
Feb 15, 2008, 10:02 PM
Post #40 of 42
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Registered: Dec 13, 2002
Posts: 8390
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(This post was edited by majid_sabet on Feb 15, 2008, 10:34 PM)
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yokese
Feb 15, 2008, 10:11 PM
Post #41 of 42
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Registered: Jan 18, 2006
Posts: 672
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glytch wrote: While I agree with your general sentiments re: majid, something's awry with your math on the forces generated by redirects. Using your math, cos(45) = sqrt(2)/2, so 2*F*sqrt(2)/2 = sqrt(2)*F ~= 1.4*F Other than that, though, right on. This thread borders on silly. Damn.... you're right (damn calculator in radians!). An apology is due: My apologies, Majid, the extra force is 40% as you correctly stated. I stand by everything else I said. Thanks glytch.
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majid_sabet
Feb 15, 2008, 10:18 PM
Post #42 of 42
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Registered: Dec 13, 2002
Posts: 8390
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yokese wrote: glytch wrote: While I agree with your general sentiments re: majid, something's awry with your math on the forces generated by redirects. Using your math, cos(45) = sqrt(2)/2, so 2*F*sqrt(2)/2 = sqrt(2)*F ~= 1.4*F Other than that, though, right on. This thread borders on silly. Damn.... you're right (damn calculator in radians!). An apology is due: My apologies, Majid, the extra force is 40% as you correctly stated. I stand by everything else I said. Thanks glytch. I am not here to proof right or wrong I am here to learn from you guys as well thank you all and no apologies needed MS
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