New Pit Rope Question

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Re: New Pit Rope Question

Postby Billy » Mar 28, 2012 9:25 pm

I took 1 step at the bottom of deep well, 292', and was off the ground.

I didn't see the part about what happened to the rope then -- :yikes:
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Re: New Pit Rope Question

Postby Chads93GT » Mar 28, 2012 9:30 pm

Doesnt matter what happend to the rope. I could have just as easily said "Mystery Falls" or Valhalla, or Cagles. The point is >1% streach and you are instantly climbing. The destruction of the rope was covered in another thread.

Will I ever buy another talon rope? Probably not. Ive scorched mine so bad without even rappelling that fast, but, thus is the results of the material used in construction. Oh well.
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Re: New Pit Rope Question

Postby OUT-OF-BOUNDS » Mar 28, 2012 9:40 pm

Im about to order 250ft of PMI pit rope:)...... When I go on my canyon trips out west I use 9mm static as it is easier to carry for the OP, but I am just not sure about 9mm for caving. :) yet at least...... I have noticed when I have bounced into pits on 10mm static rope that there is an Elastic factor of a few inches too.
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Re: New Pit Rope Question

Postby NSS8921 » Mar 29, 2012 7:01 am

Scott McCrea wrote:I sometimes use an 8mm polyester rope for pushing leads. Yes, the rigging is impecable and redundant.


Scott, what brand 8mm rope and what brake device do you use? I have used my BMS mini-rack and SMC 6-bar rack on 9mm EZ Bend and found the combinations fast but controllable. That's with 240 lbs. total weight. I would hesitate to try 8mm unless it is quite stiff.
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Re: New Pit Rope Question

Postby Scott McCrea » Mar 29, 2012 7:08 am

It's 8mm polyester core and sheath by Cancord. Gonzo Guano Gear sells it. I usually rappel with a Munter hitch with this rope. It is pretty stiff and speed wise I would compare it to clean, new Pit Rope. That being said, I don't really like the 8mm Cancord. The sheath is lumpy. Like the tightness is not uniform. Makes for a jerky rappel. I'm not sure if this is just my hunk of rope or all 8mm Cancord is like this.
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Re: New Pit Rope Question

Postby chh » Mar 29, 2012 3:13 pm

Scott McCrea wrote:It's 8mm polyester core and sheath by Cancord. Gonzo Guano Gear sells it. I usually rappel with a Munter hitch with this rope. It is pretty stiff and speed wise I would compare it to clean, new Pit Rope. That being said, I don't really like the 8mm Cancord. The sheath is lumpy. Like the tightness is not uniform. Makes for a jerky rappel. I'm not sure if this is just my hunk of rope or all 8mm Cancord is like this.

I found that lumpiness a little strange as well, it definitely performed differently than other 8 mil I've gone short distances on. I will say also that the lumpiness was less noticeable when I was using my Simple than when I was using a munter. I will also say that just a plain old munter works remarkably well in this cord, despite the lumpiness. Other smoother cords I've been on have also been faster with a munter.
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Re: New Pit Rope Question

Postby Caver John » Mar 29, 2012 3:54 pm

Anyone ever use edelrid superstatic in cave? I picked up 100m of it for srt, rappelling, and zipline use but havnt had much chance to put it through its paces. It has a low elongation of like 3+ % and a tight sheath. I think it would hold up well in cave. It's more supple than pit rope though.
Any experience with it?
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Re: New Pit Rope Question

Postby Extremeophile » Mar 29, 2012 4:25 pm

Chads93GT wrote:Doesnt matter what happend to the rope. I could have just as easily said "Mystery Falls" or Valhalla, or Cagles. The point is >1% streach and you are instantly climbing. The destruction of the rope was covered in another thread.

Will I ever buy another talon rope? Probably not. Ive scorched mine so bad without even rappelling that fast, but, thus is the results of the material used in construction. Oh well.

I've seen some information posted in this thread that doesn't look correct. According to PMIs datasheets, with a 300lb load, Pit Rope has a 1.6% elongation and Talon has a 1.1% elongation. The lower elongation with the polyester core Talon makes a big difference when climbing, but it's probably not noticeable during rappel. The sheath of Talon rope is Nylon, same as Pit Rope. I think any scorching of the rope is due to differences in how it was used, not construction.
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Re: New Pit Rope Question

Postby chh » Mar 29, 2012 6:09 pm

Caver John wrote:Anyone ever use edelrid superstatic in cave? I picked up 100m of it for srt, rappelling, and zipline use but havnt had much chance to put it through its paces. It has a low elongation of like 3+ % and a tight sheath. I think it would hold up well in cave. It's more supple than pit rope though.
Any experience with it?


Though not in a cave, i've used the Edelrid 10mm superstatic. It's static elongation is listed at 4%, but the 11mm is probably closer to 3%. I found it comparable to other 10mm nylon static ropes I've used. A little bouncy for longer drops, but just fine for anything shorter. Don't think I've been on that particular rope for anything more than 100 feet FWIW. The knotability was pretty decent as one would expect for a slightly bouncier rope.
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Re: New Pit Rope Question

Postby GroundquestMSA » Mar 29, 2012 9:05 pm

Extremeophile wrote:I've seen some information posted in this thread that doesn't look correct. According to PMIs datasheets, with a 300lb load, Pit Rope has a 1.6% elongation and Talon has a 1.1% elongation.


Thank you. So what does it mean that me and my 130lb frame stretched 80 ft. of Pit 6 inches?
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Re: New Pit Rope Question

Postby Cody JW » Mar 29, 2012 9:09 pm

130lbs !! Now I see why you use 8 mil. I bet you can move through a cave with ease, especially if you are young.
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Re: New Pit Rope Question

Postby Chads93GT » Mar 29, 2012 9:39 pm

Extremeophile wrote:
Chads93GT wrote:Doesnt matter what happend to the rope. I could have just as easily said "Mystery Falls" or Valhalla, or Cagles. The point is >1% streach and you are instantly climbing. The destruction of the rope was covered in another thread.

Will I ever buy another talon rope? Probably not. Ive scorched mine so bad without even rappelling that fast, but, thus is the results of the material used in construction. Oh well.

I've seen some information posted in this thread that doesn't look correct. According to PMIs datasheets, with a 300lb load, Pit Rope has a 1.6% elongation and Talon has a 1.1% elongation. The lower elongation with the polyester core Talon makes a big difference when climbing, but it's probably not noticeable during rappel. The sheath of Talon rope is Nylon, same as Pit Rope. I think any scorching of the rope is due to differences in how it was used, not construction.


I am not sure where I got the 6% number at, I reread the stats and for some reason that stuck in my mind. Oviously it was wrong.

You could be right about the scorching. Who knows!
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Re: New Pit Rope Question

Postby PeterFJohnson » Mar 29, 2012 10:14 pm

Static rope is often defined as any rope that has less than 6% elongation at 10% of its minimum breaking strength. I believe this is a US cordage institute standard. I think the European figure is 5%. Of course under most uses you are puttting far less than 10% of the mbs on the rope and are therefore elongating the rope far less than 6%. Groundquest, in your example you are experiencing less than 1% elongation.

A interesting effect of this is that a rope of smaller diameter, having a lower mbs, might be listed as having a greater % elongation compared to a larger diameter rope even though in practice they will stretch equally under the same weight. In order to avoid this, you often see rope manufactures specify a weight along with a % elongation like in the example given by Extremeophile.
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Re: New Pit Rope Question

Postby Chads93GT » Mar 29, 2012 10:25 pm

thats why i was thinking 6%
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Re: New Pit Rope Question

Postby NZcaver » Mar 30, 2012 12:32 am

For what it's worth, the Karst Sports website states "Static or Low Stretch Ropes ... will stretch less than 4 percent when loaded with a 200 pound load and many will stretch less than 2 percent at this load."

Of course different manufacturers and retailers may have different interpretations of what constitutes static. Most cavers who try rappelling and ascending on a few different rope types generally get a feel for what kind of stretch and friction etc they like, and what they don't. I found 8mm was a little fast for me, but not as fast as the 5.5mm I tried. Once.

It's hard to go wrong with Pit Rope, but I think next time around I'll pick up some 10mm instead of 11mm for general use. I started out caving mostly on 10mm Beal low stretch many years ago, and was pretty happy with it.
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