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16-Nov-2011 11:51:42 AM
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Hello everyone,
ive got a problem. i cant get the slack out of my rope. everytime i load it., it sinks in the centre. i expect this but it happen so low to the ground. i was rigging from tree to tree.
how far would i have to be off the ground. i thought about doing the same setup at home with more height.
help please. im using mammot 50m and a vertical harness with a single camp pulley and 4 biners and wrap arounds and sling tape.
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16-Nov-2011 11:59:40 AM
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Use static rope.
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16-Nov-2011 12:27:19 PM
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its surposed to be static rope. thats what i got told by the seller on ebay.
if i was to use more height would it get me off the ground.
i weigh 84kg
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16-Nov-2011 12:33:31 PM
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Read up on the consequences of making your traverse line too tight before you die.
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16-Nov-2011 1:46:38 PM
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40 metres between tree say 5degree sag is 1.7 metre droop and your plus gear are 100kg or 1000 Newton tension in rope is is 5.7kn per strand , 10 degrees 34 sag t = 2.8 kn . with 40 m between tress 1.7 msag means rope has stretched to 20.072 metres which is only 0.3% of strech so certainly static
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16-Nov-2011 1:53:21 PM
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On 16/11/2011 widewetandslippery wrote:
>Read up on the consequences of making your traverse line too tight before
>you die.
Do you tell slack-liners this?
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16-Nov-2011 3:39:11 PM
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On 16/11/2011 Wollemi wrote:
>On 16/11/2011 widewetandslippery wrote:
>>Read up on the consequences of making your traverse line too tight before
>>you die.
>
>Do you tell slack-liners this?
Yes. Tight enough to slackline is not tight enough to break tape (usually).
Look at it this way, if there is no sag, the tension taken on the rope is infinite... the nature of geometry and physics.
look up a slackline force calculator, I know there are some, or I can run some numbers on the one I programmed.
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16-Nov-2011 4:10:06 PM
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On tension of tyrolean V slack-lines -
My comment is quizzical, and not sardonic. I don't quite get the forces thing when so-called slack lines frequently appear very taut indeed.
Additionally the angle of the sag in tyroleans also exceeds acceptable forces, doesn't it?
- http://www.southeastclimbing.com/faq/faq_anchor_forces.htm#space
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16-Nov-2011 5:19:48 PM
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Wollemi I don't quite get it in th real world but its factual an overtightend horizontal carrageway is a timebomb. There was a column8 snippet the other day about why balls on towbars where people have used them for whinching have worn the ball! Different buit similar.
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16-Nov-2011 5:25:47 PM
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Ahh, column 8 - the great repository of Western physics.
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16-Nov-2011 5:35:18 PM
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Pat, I agree some things baffle me at times. Horizontal tight lines have a lot of variables that if f---ed up are catastrophic and worthy of mention. Its like a. Piano tuner can tune a piano tyhen the owner hits a certain key and the wire snaps.
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16-Nov-2011 8:00:53 PM
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well i dont want it to break or fail. shit! ive tested the rope and i cant get the slack out of it unless i do it at a height. it will pull down i know this. the problem is, is it going to break? i can just go home tonight and study my documents a little more and do somemore planning so things pan out a lot better
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17-Nov-2011 1:28:16 PM
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Tyrolean traverses are a vector pull situation. That is, you are applying force to 2 anchors 90 degrees to the direction of pull. This means you are applying several times more than your 80+kg static mass.
Check this website. It has an awesome simulator:
http://www.tagsafety.com/library6.asp
At zero degree rope angle for your weight, you are applying 28kN to each anchor.
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17-Nov-2011 2:38:21 PM
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On 16/11/2011 cjradloff76 wrote:
>its surposed to be static rope. thats what i got told by the seller on
>ebay.
>
Given the apparent stretchiness of your rope do you have any real reason to assume the ebay seller knew what they were talking about when describing it as a 'static' rope? ;-)
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17-Nov-2011 4:00:28 PM
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On 17/11/2011 stealth wrote:
>Tyrolean traverses are a vector pull situation. That is, you are applying
>force to 2 anchors 90 degrees to the direction of pull. This means you
>are applying several times more than your 80+kg static mass.
>
>Check this website. It has an awesome simulator:
>
>http://www.tagsafety.com/library6.asp
>
>At zero degree rope angle for your weight, you are applying 28kN to each
>anchor.
Actually at 0 degrees the load is infinite ! at 1 degree it would be (1000/2) /sin 1degree N which is 28.6kN
If your rope is 20 metres between tree then 1 degree is sag of 17 cm and an elongation of 1.4 mm or stretch of 0.14% which is definitely not dynamic rope. All simple trig and pythagorus . At those type of loads the trees will be moving under load increasing the sagging but thereby reducing the loads .
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17-Nov-2011 6:12:02 PM
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I think the most obvious solution would be to double up the rope then tension both strands with a rescue Z, it would only sag half as much, or go for four strands for only a quarter of the sag.
I attended a rescue seminar where this was the solution for a Tyrollean rescue involving two people across a 25 meter gap in the gorge, then using an English reeve to lower, connect, and then raise the casualty, before then hauling back to the edge of the gorge.
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18-Nov-2011 10:40:45 AM
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im lost. i need more info. cheers
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18-Nov-2011 11:49:22 AM
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Cue the classy drawing from mikl.
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18-Nov-2011 5:06:05 PM
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ive been thinking about this one. as with my dynamic rope i dont think its feasible to use it. ill check the other rope and see if its static. its EDELRID brand so it should be.....it better be... or else theres going to be one less ebayer. BECAUSE ITS GOING TO COST ME MORE MONEY TO GET STATIC ROPES. i wish they sold those in 50m bundles like they do with dynamic ropes. would make it a lot easier for those people who abseil. like myself after the 3/12. better than buying it off the spool. TOO EXPENSIVE for someone whos on a window cleaners wage
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18-Nov-2011 5:37:32 PM
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On 18/11/2011 cjradloff76 wrote:
>ive been thinking about this one. as with my dynamic rope i dont think
>its feasible to use it. ill check the other rope and see if its static.
>its EDELRID brand so it should be.....it better be... or else theres going
>to be one less ebayer. BECAUSE ITS GOING TO COST ME MORE MONEY TO GET STATIC
>ROPES. i wish they sold those in 50m bundles like they do with dynamic
>ropes. would make it a lot easier for those people who abseil. like myself
>after the 3/12. better than buying it off the spool. TOO EXPENSIVE for
>someone whos on a window cleaners wage
I noticed your earlier post deletion/change.
Are you aware that Edelrid make both static AND dynamic ropes?
On a window cleaners wage you ought to be able to claim the rope cost as a tax deduction?
I know of a number of companies who will sell you static rope off the spool on a $/m basis. Custom orders appear to be no problem to them from my experience...
The alternative is to find some mates and go % for what you require off your own spool.
By the way, a standard spool length is 200m.
I hope you find what you want.
Hmm. This tyolean traverse, where is it? What are you actually trying to achieve?
~> A dynamic with sag may well meet the need...?
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