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Used ropes for sale?


Macciza

24-Apr-2007
12:17:25 PM

On 24/04/2007 BigMike wrote:
>On 23/04/2007 Macciza wrote:
>>Hey - I probably got some spare ropes if you need some extras . . .
>
>They've been lying around in the back of my car next to that old battery
>for the past six months?
>
>(Just jivin'!)

Nah
Haven't got a car - Had them on various cliffs instead, Doggie, HaHa etc
And I've located the old, old Dogface ropes as well so they should be available soon.
Cars are too mush like shelfs and we all know what shelfs can do to ropes . . .

(I'm Serious!)


tnd

24-Apr-2007
12:17:54 PM

On 24/04/2007 Sabu wrote:
>seriously wat better way to seek help and advice than a climbing forum
>full of people who know about rigging stuff. asking anywhere else would
>be stupid.

And get multiple replies giving conflicting advice, all saying they're right... :-) Gotta love web forums.

>
>btw attention seeking isn't a major sign of anything serious, it's pretty
>normal behaviour, just look around and u can see all kinds of people doing
>it in their own way. When it's on a large scale, however it's an indication
>of some personality issues but wat u've argued is no way near that point.
>
>say for example, many public annoucements, pm's, etc. might classifiy
>but could also only be a result excitement and not the need for attention.
>
>You asked!

Thanks Dr!


Macciza

24-Apr-2007
12:20:12 PM

On 24/04/2007 rodw wrote:
>
>>> i dont even want to think about trying to undo a loaded fig8 afer a
>>200m jump!!
>
>Does it matter????? I doubt you'll use the rope again so you can just
>cut it off.

Ummm, if you are not doing anything with the, ahh, rope . . . I'll . . .


nmonteith

24-Apr-2007
6:28:37 PM

Please tell me you are testing this system on something smaller before comitting to the 250m jump....
(i'd like to still have a photo editor this time next week).


tnd

26-Apr-2007
8:48:18 AM

He's testing it on a 125m jump so as to incorporate a 100% safety factor.


Macciza

26-Apr-2007
9:52:54 PM

On 26/04/2007 tnd wrote:
>He's testing it on a 125m jump so as to incorporate a 100% safety factor.

No Dude - 125 over 250 = 1/2 = 50% as safe
Half as much rope = twice as dangerous
Also I'd only recommend Jakes Wombat Chocks or the secret DeadCow Anchors for you main line.
Please be careful mate - your scaring me . . . come aiding instead . . That lines begging . . .
Also if you remove a strand or two from your ropes core as discussed they'll be more dynamic


Sabu

26-Apr-2007
10:36:21 PM

when are u doing this? by the sounds of it, it's like within the week!


Chuck Norris

26-Apr-2007
11:13:35 PM

On 26/04/2007 Macciza wrote:
>
>No Dude - 125 over 250 = 1/2 = 50% as safe
>Half as much rope = twice as dangerous

goddam it you're right..for complete certainty of outcome he should go for 250m of rope on a 125m jump -
200% safe, and the ropes would be OK to use after the jump.


Macciza

26-Apr-2007
11:29:05 PM

>250m of rope on a 125m jump - 200% safe,
Excellent margin of safety there - better than 100%

>and the ropes would be OK to use after the jump.
Correct - zero impact force on rope though maybe a bit of cleaning

TonyB

28-Apr-2007
2:22:39 PM

At 250m you should be close to terminal velocity (no pun intended). Together with the fact that that the rope's total surface area is several times that of a human, air friction on the rope should gives an even lower terminal velocity, and more quickly reached terminal velocity, than a free jumper. At 125m your maximum fall speed shouldn't be a lot less. 250m of rope will give twice the deceleration distance that 125m gives. I would hence expect that the loading on the rope would be less for a 250m jump than for a 125m jump.

It would be interesting to time each jump, including the time for the rope to take up slack, as well as the time to stop falling. You could try throwing the rope over with a dummy attached (again, no pun intended).


wallwombat

29-Apr-2007
10:26:32 AM

I think that if the NPWS rangers became aware of this they might seriously consider banning rope sports (ie climbing) from the gorge. Climbing has been banned before, largely due to the exploits of base jumpers. The ban was lifted because the were convinced by climbers that there is a big difference between base jumping and climbing. A 250 m rope jump by climbers might just be enough to convince there isn't a difference.
It would be a shame to get climbing banned from the gorge for the sake of a few seconds of adreneline rush and some photo ops.

DJ Biggs

29-Apr-2007
10:06:15 PM

question is.... are you going to heed it?

TonyB

30-Apr-2007
8:00:34 AM

Perhaps NPWS rangers also need to be educated on the difference between base jumping, rope jumping and climbing.
Maybe they could also be taught the difference between a bulldozer to cut trails through native bushland, a 4WD car, and a mountain bike.


wallwombat

30-Apr-2007
10:27:27 AM

I think taking the approach that rangers are all reactionary f*#kwits who don't know their asshole from breakfast when it comes to outdoor activities isn't going to get us anywhere.

Bungonia is a State Recreation Area which caters for climbers, cavers , canyoners and other outdoor types. It sees a lot of traffic (I don't mean cars) each year. The rangers there are generally pretty good blokes who do have an understanding of outdoor activities. Try hooning around Bungonia SRA in your 4wd and see how long you last.

My only point is that in terms of safety I don't think they would see much difference between jumping of the top of the gorge with a parachute and jumping of the top of the gorge with a bloody long climbing rope tied to you.

To tell you the truth, I don't see much difference either.

Dan Osman, who was probably the world's most famous rope jumper isn't around to argue that its a safe activity. All thats left of him is a stain on a patch of granite somewhere in Yosemite.

I'm not saying, don't do it. All I'm saying is be careful because you might go down in history as the dickhead that got climbing closed at Bungonia.Or even worse, the DEAD dickhead that got climbing closed at Bungonia.


gordoste

30-Apr-2007
11:03:51 AM

On 30/04/2007 wallwombat wrote:
>I'm not saying, don't do it. All I'm saying is be careful because you
>might go down in history as the dickhead that got climbing closed at Bungonia.Or
>even worse, the DEAD dickhead that got climbing closed at Bungonia.

well said.

rightarmbad

30-Apr-2007
11:04:50 AM

How do you get a fall factor greater than 1? You are falling the same distance as the length of rope out. Fall factor 1.
What sort of forces have you figured for your anchor rope? They gotta be pretty high.

TonyB

30-Apr-2007
11:43:19 AM

The fall factor is 1. The simple theoretical shock load isn't any different whether jumping 250m or 2.5m. The actual shock loading should be reduced because of air resistance reducing the fall speed. The weight of the rope adds a little to the static load on the anchors. The forces don't seem at all dangerous (not that I'd do it) but the danger would appear to be heating via rope friction, as caused Osman's demise, or cutting on edges.
I assume you plan to jump with the rope already hanging over the drop ?


pat

30-Apr-2007
1:58:22 PM

All very interesting, but when is this all going to actually happen and when will we see the photos posted?


Dom

30-Apr-2007
2:46:46 PM

On 30/04/2007 pat wrote:
>All very interesting, but when is this all going to actually happen and
>when will we see the photos posted?

I agree Mousey. Less text more pics!


anthonyk

30-Apr-2007
4:09:08 PM

if someone was to do something like that, i'd be very hesitant about people using ropes that are anything less than brand new, mint condition. all your assumptions about stretch and load that a rope can take are based on assumptions that the forces will get distributed evenly throughout the rope. its a nice little assumption, being able to cancel out a whole lot of numbers because you assume the force gets distributed evenly.

if the rope is less than perfect you can get sections where the stretch is a little bit different. either from wear, from taking falls, anything, older ropes will undoubtedly have slight variations in them.

the problem is you end up with an interface between sections with slightly different properties, which will cause disproportionate loading.

one thing to remember is that the energy you need to absorb in a 250m fall is massively more than in a 10m climbing fall. any slight irregularities in the properties of the rope can lead to a whole lot more energy being concentrated on one point than being spread evenly along the rubber band. there's plenty enough energy being thrown around to snap a rope if it gets concentrated at particular points.

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