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19-Nov-2011 10:23:02 AM
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what exactly are you after , as the amount of sag even with static rpoes can be qite large . Mammut define static as less than 5% stretch when loaded with 150kg you will have more load on your rope than this if you are under low sag
at 5% for every metre your centre is from the support you will have 32 cm sag and for 100kg load a force in the rope of
5% 32 cm T= 156 kg or 1.56kN
4% 28cm , T=178 or 1.78 kN
3% 24 cm , T =208 or 2kN
2% 20 cm , T=25 kg or 2.5kN
1% 14 cm T=357 kg or 3.5kN
so all these loads will be in excess of the definition of static and as the loads increase presumably there will additional stretch
you really need to work out what you want as possibly the only way to get the less sag would be to go to wire cable
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19-Nov-2011 10:42:13 AM
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On 19/11/2011 lacto wrote:
>what exactly are you after , as the amount of sag even with static rpoes
>can be qite large . Mammut define static as less than 5% stretch when loaded
>with 150kg you will have more load on your rope than this if you are under
>low sag
>at 5% for every metre your centre is from the support you will have 32
>cm sag and for 100kg load a force in the rope of
>
>5% 32 cm T= 156 kg or 1.56kN
>4% 28cm , T=178 or 1.78 kN
>3% 24 cm , T =208 or 2kN
>2% 20 cm , T=25 kg or 2.5kN
>1% 14 cm T=357 kg or 3.5kN
>
>so all these loads will be in excess of the definition of static and as
>the loads increase presumably there will additional stretch
>you really need to work out what you want as possibly the only way to
>get the less sag would be to go to wire cable.
And lacto has hit the nail on the head.
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19-Nov-2011 10:56:59 AM
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On 19/11/2011 shortman wrote:
>And lacto has hit the nail on the head.
cm or mm sag?
Seems like an awful lot if it is cm...
~> an example; suppose one has a span = 2m, therefore 'centre' is 1m out, therefore sag = 32cm?? (If I have followed lacto's post correctly). It is certainly possible to have that much sag, but with a drum tight rope in the above example, and bodyweight loading, I would not expect that much sag.
~> Am almost inspired to go and play with a static rope now!
As an aside, I think Bluewater ropes consider a static has <3% stretch, but have not been to their website recently to confirm this.
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19-Nov-2011 12:10:27 PM
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im a very small business which doesnt make enough money to pay tax. i have an ABN for sub-contracting. ive never had to use it yet. im going to be testing my traverse line at my parents place in their backyard. theres enough height from the patio to the back tree. i tried in the local park it failed to get off the ground "too much sag/slack". im going to try it at home before i try it outside to ensure it works properly. i cant go home at the moment because my mum and dad aint home.
on the other hand thanks for the measurements and the loading heads up. ill give it a tree. i do have extra slings if need be.
most of my slings are 22kn.
prayers everyone
ill post pictures on my website at http://cjradloff762.webs.com/tyroleantraverse.htm
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19-Nov-2011 1:10:52 PM
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ok i am lost why are you try to set one up. from my experience setting up slack lines you can tension a static line with a z drag and a grigri or with some prussiks. really easy and only have like 1m or so sag out of 15 or 20 meter line. (this was when we wanted to try and balance a rope rather than tape). as for buying rope you can buy blue water rope 11.2 mm for like $5 a meter and that is one of the dearest brands.
another way of treversing which i like is to set up a fixed line. then have another one 5 meters longer then just hang on the fixed line then run a abseil device down the longer line and then once you reach the lowest point of the treverse prusik back up the other side on the longer line, the advantage is you decent onto the line is controlled and if the treverse is long or steep going back up is easier and not just hand over hand work.
it also doesn't matter then if you have 10 meters of sag or one it works the same. also have an extra line of safety.
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19-Nov-2011 1:14:18 PM
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On 19/11/2011 cjradloff76 wrote:
>i
>(snip)
>
>ill post pictures on my website at http://cjradloff762.webs.com/tyroleantraverse.htm
I had a look at this website and have to say I was somewhat concerned by what I found!
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19-Nov-2011 1:35:31 PM
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Yeah, I had a look too. Cj, u really should be very careful rigging something to a patio. In fact I think u should abandon your whole project and giving advice on the web about how to set up a tyrolean traverse should probably wait until u have a working line.
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19-Nov-2011 1:52:12 PM
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This has to be the best Troll in a while...
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19-Nov-2011 2:06:23 PM
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On 19/11/2011 timfreddo wrote:
>This has to be the best Troll in a while...
Sadly, I doubt that it is a troll.
On 19/11/2011 kuu wrote:
>On 19/11/2011 cjradloff76 wrote:
>>i
>>(snip)
>>
>>ill post pictures on my website at http://cjradloff762.webs.com/tyroleantraverse.htm
>
>I had a look at this website and have to say I was somewhat concerned by what I found!
+1
Start; ... Tongue now firmly in cheek.
Ahh, but where is your sense of adventure kuu?
Surely you can see our young (35 apparently), poster is mindful of his mum, his budget, and has been doing his homework?
Andya can't get much better inspiration than looking at pictures of a tyrolean off Lost Arrow Spire (one of his links), to get that abseiler* blood pumping eh?
(*Home page states intention to abseil off Ipswich water tower, amongst greater tyrolean ambitions at Nth Gorge & Limestone Park!).
Have you forgotten what it is like to be young and adventurous?
End; ... Tongue removed from cheek.
You have great tact.
I am sure that some other Chocky regulars, when they get to this, will say what you (& I), may have thought in passing!
Hmm. I wonder if his mum is internet savvy and has read Clinton's website?
Heh, heh, heh.
~> Hey Clinton, there is plenty of sag in this line.
Have you considered using ascenders?
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19-Nov-2011 9:27:27 PM
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On 19/11/2011 cjradloff76 wrote:
>ill post pictures on my website at http://cjradloff762.webs.com/tyroleantraverse.htm
Had a look at your web site, It is very bad and dangerous that you are offering advice on how to so something which it would appear that you have little knowledge on how to do safely. Either you of someone else who uses the information could have a serious accident as a result.
I my experiences tyrolean traverses are mostly set up for no real purpose except fun and you end up bored of the notion by the time you are half way across the rope anyway. The situations which may actually require a tyrolean traverses are mostly at the top of advanced & isolated climbs e.g. totem pole or rescue related.
If you are still really keen on the notion of a tyrolean traverse i would suggest paying a professional to teach you how to set one up properly and safely.
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19-Nov-2011 10:41:58 PM
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>Seems like an awful lot if it is cm...
>~> an example; suppose one has a span = 2m, therefore 'centre' is 1m out,
>therefore sag = 32cm?? (If I have followed lacto's post correctly). It
>is certainly possible to have that much sag, but with a drum tight rope
>in the above example, and bodyweight loading, I would not expect that much
>sag.
>~> Am almost inspired to go and play with a static rope now!
>
>As an aside, I think Bluewater ropes consider a static has <3% stretch,
>but have not been to their website recently to confirm this.
simple rightangle triangle and pythagorus
base is 1 ,s ag is X and hypotenuse is 1.05 (5% stretch ) so X = square root of (1.05X1.05 -1X1) or the root of (1.1025-1 =0.1025) or 0.320156 or 32 cm from this you can scale the force in the rope by half the weight as load carried by rope on bothside of the load divides by 0.32 X1.05 to give answer in kg convert to N by multiplying by 10
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19-Nov-2011 11:57:54 PM
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3% stretch in a verticle hang with body weight. Dweebs. Horrizontal will increase the load on the anchors/rope exponentially and stretch the rope heaps more.
I've set horrizontal tyroleans at work. Use cable(steel wire rope(SWR)), it'll still stretch. 5%sag ish as it gets tighter, it stretches more... 5%, 5%, 5%, 5%. Unless your weight is negligable compared to the weight of the tyrolean rope itself. 100kg person x 5%sag = 2000kg on the anchors. Trying bouncing a bit when your hanging on it.
I've seen 80mm SWR stretch (@ 50,000pound miles). And once changed 6x185mmSWR because it stretched. (With 5000reps at 1200ton)
I've also snapped 11mm 'static' at work, it ferkin stretched heaps (20%?) before it went 'twang'.
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20-Nov-2011 10:30:29 AM
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On 19/11/2011 Paul wrote (above):
~> Good advice for this particular thread!
@ lacto
Do you enjoy maths as much as climbing?
~> all good fun eh!
Heh, heh, heh.
On 19/11/2011 Cool Hand Lock wrote:
> 3% stretch in a verticle hang with body weight.
That rang my memory bell. You are right, anything more will stretch a static more!
Re tyroleans.
The only few I have ever done had quite a lot of sag, though I considered it went with the territory and was not an issue at the time, as I was more concerned that my anchors did not blow out.
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20-Nov-2011 10:48:27 AM
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i got it up and im on it. my sister took those pictures for me.
ok it was static rope and it has been a lot of fun.
ive moved it from the patio to the tree on the other side of my yard.
im pulling it down later on.
the trampoline was only put there in case it did fail. well i didnt.
AND IM NO TROLL!
this was the plan to traverse this
at a later date. the further out i go the more rope i need but im not taking the risk. im going to do somemore research and study my notes more. ill need to do somemore practice runs before i do this. im not trying to get myself killed. i know about safety and i checked my anchors 12 times before i loaded the rope.
im still in training for my course in abseiling on the 3/12.
it was only up for testing.
and it worked as you can see.
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20-Nov-2011 11:22:42 AM
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On 20/11/2011 cjradloff76 wrote:
>im not trying to get myself killed. i know about safety and i checked my anchors 12 times before i loaded the rope.
>im still in training for my course in abseiling on the 3/12.
Checking is good. Especially when you know about what you are checking for.
Your photos show an undisputable keeness on your part.
Perhaps when you do your abseiling course you may find others who are suitably keen, and together you can split the cost associated with getting a professional guide service to help you rig your tyrolean on your ambitious project.
You might like to ask that service about helpful things such as redundancy (there is none evident in your photos); lowering out instead of 'flying-foxing' it (some pulleys are not designed/rated for certain tasks); safe methods of anchoring in a natural environment; handy hints on how safely to initially get your rope across the span that you want to traverse, (are you aware that wet ropes are not as strong as dry ones?); and once set up, how to get to the opposite side after you have reached the low point in the sag.
☺
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20-Nov-2011 11:59:12 AM
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On 20/11/2011 cjradloff76 wrote:
Hmm.
You have not met either of these two gents on any of your adventures have you?
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20-Nov-2011 12:43:20 PM
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On 20/11/2011 cjradloff76 wrote:
>i got it up and im on it. my sister took those pictures for me.
>
>
>
>
>
>
>ok it was static rope and it has been a lot of fun.
>
>ive moved it from the patio to the tree on the other side of my yard.
>im pulling it down later on.
>the trampoline was only put there in case it did fail. well i didnt.
>AND IM NO TROLL!
>
>this was the plan to traverse this
>
>height=480>
>at a later date. the further out i go the more rope i need but im not
>taking the risk. im going to do somemore research and study my notes more.
>ill need to do somemore practice runs before i do this. im not trying to
>get myself killed. i know about safety and i checked my anchors 12 times
>before i loaded the rope.
>im still in training for my course in abseiling on the 3/12.
>it was only up for testing.
>and it worked as you can see.
>
>
>
some things to consider
1) using a tandem pully will prevent the cheeks of the pulley binding and creating unnecessary friction on the rope.
2) Unless you are using crazy thick rope like 13mm it would be a very good idea to double the rope and use two pullies.
3) have ascenders of some way to get back up the other sode of the rope, the further across you get the steeper angle will get, consider the force the ascenders will put on the rope.
lets think about angles and forces in the system when using a single rope.
say you decide you want to have a 10% safe working load on your system, to allow for things like if the system is shock loaded, sharp edges, existing uv wear and abrasive wear on the rope. Say your rope is Blue Water 11mm which is about 30kn in strength, you tie a figure 8 in the end, which weakens the rope by about 30% (varies according to rope construction and diameter) so you are now down to 21kn. You have your rope tensioned so it creates an angle of 170 degrees when your weight is on it, if you weigh 100 kg then you will be applying a force of 5.725kn to each anchor or 11.45kn to your rope. so your weight could be loading your rope to 54% of the breaking strain of the system asuming your repe is new and in excelent condition (not second hnd off ebay). So by using two ropes and reducing the angle you can make things safer.
4) if you are having the ropes tensioned super tight creating stupidly big angles build a fuse into the system which will slip before you create a force which could create failure, e.g. few fully loaded whale tales riged inline for this purpose.
5) From your photos either your pants are super high or your harness is sitting on your hips and not your waist, an inpropper fitted harness could mean that you fall out of your harness if you flip upside down.
6) gravity load your karabiners, the vibration of a pulley on a rope can cause gates to become undone.
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20-Nov-2011 3:48:39 PM
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from pauls post if you only want a safety factor or 10 % your are crazy 200 to 300 % would be better as failure is you DEAD or MANGLED . the crabs you use are 20+kN but 1.1 kN would be a 10% safety factor so you have a sf of 20+ with a normal crab
Also paul is out in his forces on the rope actually 100 Kg and 10 derees of sag ( and the centre point of the rope will give the largest load of the rope is
100/2*9.81/ sin 10 =2.86 kN in the rope both in tension from the centre point and hence will load each anchor point with 2.86 Kn in the direction of the rope . Putting weight on an ascender wont increase the loading at all as the weight that goes on the ascender is removed from the load you have from your harness.
Can't emphasise enough that large safety margins are sensible and 2 ropes or more even more sensible . Be absolutely sure within yourself that your setup is good before you launch
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20-Nov-2011 5:39:10 PM
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On 20/11/2011 lacto wrote:
>from pauls post if you only want a safety factor or 10 % your are crazy
Probably not the clearest explanation on my part, by 10% I ment putting no more than 10% of the weakest point of the system, so a safety factor of 10 or 10% safe working load, not a 10% safey margain. 10% safety margain would be very scary.
> 200 to 300 % would be better as failure is you DEAD or MANGLED . the crabs
>you use are 20+kN but 1.1 kN would be a 10% safety factor so you have a
>sf of 20+ with a normal crab
>Also paul is out in his forces on the rope actually 100 Kg and 10 derees
>of sag ( and the centre point of the rope will give the largest load of
>the rope is
>100/2*9.81/ sin 10 =2.86 kN in the rope both in tension from the centre
>point and hence will load each anchor point with 2.86 Kn in the direction
>of the rope .
Your calculations are based on 10% sag, or an included angle of 160 deg when the pulley is in the centre of the tyrolean, my calculations were were based on 5 deg sag with the included angle of 170 degrees. both our calculations are correct although mine not explained as clearly.
the main point is the tighter the rope the bigger the forces.
Putting weight on an ascender wont increase the loading at
>all as the weight that goes on the ascender is removed from the load you
>have from your harness.
The ascender will create an increase in pressure where it is located on the rope similar to the rope running over an edge of a cliff. Not sure how big this would be or if it would be a issue, but ropes are more subject to damage while under tension.
>Can't emphasise enough that large safety margins are sensible and 2 ropes
>or more even more sensible . Be absolutely sure within yourself that your
>setup is good before you launch.
Very good advice, also ensure that your ropes are sharing the load evenly between them and both have redundancy independant of each other.
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21-Nov-2011 9:55:36 AM
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Here is a fine example of Chockstone members being welcoming and encouraging to, ah, well, I'm not sure what catagory this gent falls into. 'Aspiring abseiler' perhaps. But with all the maths and physics being discussed with a straight face, the fact that no one has mentioned potential solution to the devastating problem of one's shorts falling down when wearing a harness (or it could've been the other way round), and so being forced to wear tracksuit pants (in my opinion a dangerous compromise), worries me. ODH, why are you letting this go unaddressed? Where is your humanity?
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