New Pit Rope Question

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Re: New Pit Rope Question

Postby Scott McCrea » Mar 28, 2012 6:13 pm

Cody JW wrote:If anyone out there wants to see a copy of the accident report for Mega Well and the post accident analysis send me an e-mail ( codyjpme@att.net) and I can forward it to you. It was in a Georgia Underground issue from back in the early 90s. I suggest anyone read this before using 9 mil rope with American style rigging. "Those who do not study history are doomed to repeat it " . I know you likely will be safe in a free hang but check it out anyway, it could save your life.

This report is also available online to NSS Members in the archive section of the members page on the NSS web site. It's in the Dec 1992 (accidents that happened in 1991) issue, page 340.

Good quality 9-10mm rope from a reputable manufacturer is safe if used properly. Unlike the stuff used in this accident report.
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Re: New Pit Rope Question

Postby Chads93GT » Mar 28, 2012 6:13 pm

Jeff. That euro rope was also dynamic. Not static. Lots of bounce.

Ever climbed on dynamic? I have. It's a rodeo on rope lol.

As I said earlier. It depends on your rigging skill.
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Re: New Pit Rope Question

Postby Chads93GT » Mar 28, 2012 6:16 pm

I prefer 10mm over 11. When geared up for survey. Soaked in my wetsuit I weigh about 240lbs. That's 50 lbs of gear and water lol. Doesn't phase me on 10mm
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Re: New Pit Rope Question

Postby Cody JW » Mar 28, 2012 6:24 pm

I understand what Chad and Scott say. I just remember all the talk going on back then soon after it happened and the general theme was do not mix Euro diameter rope with American type rigging. When it comes to vertical I prefer to a as much of a safety margin as possible. I may be more cautious than some of you. If you want to use 9 mil go ahead. I just will not, especially being my size and knowing you can get increased rubbing during the frog climb as apposed to rope walker. Also less friction on rappel. To each his own.
It only takes one person to surrender a dog to a kill shelter ,but it takes many to rescue it.
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Re: New Pit Rope Question

Postby Cody JW » Mar 28, 2012 6:31 pm

Also , I like many have seen some nasty rub points on 11 mil ropes over the years, Chad spoke recently of one he had at Deep Well. Looking back on it I wonder what would of happened if I had used 9 mil to save weight. I suspect I would be well into my dirt nap by now.
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Re: New Pit Rope Question

Postby Chads93GT » Mar 28, 2012 6:45 pm

Here in Missouri I rig euro style. Why? Because all the chert will cut even 11mm in half

Also because when surveying I rig the pits for speed and for no rubbing.

I would confidently rig these with 10 or 9mm as there is no rubbing in the zig zag trip to the bottom.

To rig these with pads would be a nightmare. Repeatedly every trip.

I'll use bolts.

Pardon my spacing. iPhone lol.
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Re: New Pit Rope Question

Postby Scott McCrea » Mar 28, 2012 6:47 pm

Comparing the Euro rope in the accident to modern 9-10mm static (PMI) rope is like comparing a German sports car (or a Mustang for Chad) to an apple cart. The Euro rope used inferior nylon and inappropriate (non-static) construction. Not to mention the unknown history or the rope.

Only using 11mm rope is fine, but thin rope is rarely the culprit in an accident.

I sometimes use an 8mm polyester rope for pushing leads. Yes, the rigging is impecable and redundant.
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Re: New Pit Rope Question

Postby Cody JW » Mar 28, 2012 6:55 pm

Typically on this side of the pond most do not rig Euro style. I have seen many bad rub points happen where I did not expect them to be. I have expected a bad rub on many and had none at all. Sometimes you just may not know. I used to cave with a guy bigger than I back in the early 90s that used SSP rope instead of PMI 11 mil. This stuff appeared to be stout compared to PMI pit rope. He said he just felt safer on it, I understand. I also remembered more friction with that rope, that is why I suspect less friction with less than 11 mil. It only takes one time. You may not get a chance for a do over.
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Re: New Pit Rope Question

Postby Cody JW » Mar 28, 2012 6:58 pm

Scott McCrea wrote:Comparing the Euro rope in the accident to modern 9-10mm static (PMI) rope is like comparing a German sports car (or a Mustang for Chad) to an apple cart. The Euro rope used inferior nylon and inappropriate (non-static) construction. Not to mention the unknown history or the rope.

Only using 11mm rope is fine, but thin rope is rarely the culprit in an accident.

I sometimes use an 8mm polyester rope for pushing leads. Yes, the rigging is impecable and redundant.
Scott, you have gonads the size of grapefruits. You have my respect. Are my bootlaces safe around you ??
It only takes one person to surrender a dog to a kill shelter ,but it takes many to rescue it.
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Re: New Pit Rope Question

Postby Chads93GT » Mar 28, 2012 7:26 pm

Lol I got I to a conversation about rappelling with Bruce smith at tag or mvor. He has rappel led on 5mm cord. It's all about the strength of the "rope". Balls.
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Re: New Pit Rope Question

Postby GroundquestMSA » Mar 28, 2012 7:32 pm

I've another new pit rope question. I bought a length of PMI Pit a short time ago, after asking for input from you folks.
My first uses were so different from what I expected that I had to chop off a length of the rope and have a look at the tracer. The speed was surprising, but not shockingly so for a new rope. The stretch was the real puzzler. At the bottom of an 80 ft. drop, my slight body weight was able to stretch the rope 5 or 6 inches. I can only compare it to the few other static ropes I've used, but that seems like a lot.
Will rope shrinkage have a drastic effect on stretch? I hope so. I've since washed the rope but haven't had another chance to climb on it.

Cody JW wrote:
Scott McCrea wrote:Comparing the Euro rope in the accident to modern 9-10mm static (PMI) rope is like comparing a German sports car (or a Mustang for Chad) to an apple cart. The Euro rope used inferior nylon and inappropriate (non-static) construction. Not to mention the unknown history or the rope.

Only using 11mm rope is fine, but thin rope is rarely the culprit in an accident.

I sometimes use an 8mm polyester rope for pushing leads. Yes, the rigging is impecable and redundant.
Scott, you have gonads the size of grapefruits. You have my respect. Are my bootlaces safe around you ??


I am in no way engaging in a boastful testicular comparison, or seeking Jeff's respect, but I too have used 8mm for a handful of deeper leads in obscure Va. caves. I didn't realize that I was doing anything extraordinarily bold or risky. If it's carefully rigged, who of us is going to snap an 8mm rope?
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Re: New Pit Rope Question

Postby Cody JW » Mar 28, 2012 7:39 pm

Groundquest, you may not seek my respect but you have it. I just never considered small diameter rope. I figure if I do not have the physical wherewithal to haul an 11 mil to and through the cave I do not belong in the cave.
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Re: New Pit Rope Question

Postby Chads93GT » Mar 28, 2012 7:46 pm

Pit rope streaches what. 6%? 6" is nothing. That's normal. On a 600' drop you will climb for 45 seconds before you get off the ground.
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Re: New Pit Rope Question

Postby GroundquestMSA » Mar 28, 2012 7:58 pm

Chads93GT wrote:Pit rope streaches what. 6%? 6" is nothing. That's normal. On a 600' drop you will climb for 45 seconds before you get off the ground.


That's true. Again though, I'm comparing to other ropes and I have admittedly little experience. On the same day on a longer drop, around 100 ft., a friends 11mm rope stretched about 1 inch under my weight. I have used my brother's 7/16" on many small drops, 20' - 80' without noticing any stretch while climbing. The Pit rope was radically different, that's all.
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Re: New Pit Rope Question

Postby Chads93GT » Mar 28, 2012 8:45 pm

Talon, which is what i use on long drops, is about 1% streach. I took 1 step at the bottom of deep well, 292', and was off the ground. the deeper you go, the more it streaches. its all relative. different types of rope, different brands, will all react differently. dynamic, static, nylon, polyester (steel cable) all streach differently. Dont misconstrue static pit rope as truely static. read the product stats first so you know what you are getting into. Polyester rope is the only rope that truely doesnt really streach, but you better know what you are doing if you rig with it.
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