Rope Rigging

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Rope Rigging

Postby David Grimes » Dec 14, 2007 7:56 pm

Just curious how most people rig their ropes for the first descent into a cave.

Tied to a tree or a rock etc.

I have seen so many crazy looking rigs at the entrances to caves and I understand the purpose in some cases but it just seems some people go overboard using 30' of rope to make something resembling a spiderweb just to hook the rope they plan on descending down to.

Is this really necessary I may be missing something as I am still new to vertical caving but it still seems like a waste to me.
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Postby wyandottecaver » Dec 14, 2007 8:46 pm

it all depends of course :) mostly I just rig to a nice stout tree with 2-3 wraps and go. BUT, if I know the drop has a lot of bad ledges or overhangs I have been known to rig such that the focal point is over the pit so the drop is "free" away from the walls. Another reason for "spiderweb" rigging might be they want to rig out of a waterfall or have multiple ropes at once. except for well executed rescues, multiple ropes in a pit are generally a bad bad idea. Of course this requires some skill and know how. If you have enough rope (at least double the amount to drop the pit), rigging through a tied off rack anchored to the tree lets you lower a climber back down if they get in trouble. I rarely do this except occasionaly with new climbers though It is probably a good idea as a general safety backup. Finally, some of us are twisted enough to get perverse pleasure in creating elaborate rig systems for fun, though 95% of my caving is with simple stuff.
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Postby NZcaver » Dec 14, 2007 8:51 pm

Not really the thing to learn without being in a practical setting, but you could think of it this way.

Only use a single tree or a single rock for your anchor points if they're absolutely bombproof. What we call a Big F...ing Tree (BFT), or a BFR. Otherwise you probably should think about constructing an anchor system (if you know how), which puts the rope where you want it and/or helps minimize the chance of catastrophic failure.

Such a system does not always need to be a complex spiderweb, but can be as simple as having a high-angle redirect at the edge to make life much easier for negotiating the lip. Small details like this may not always be strictly "necessary" - but at every drop if you're always just tying the rope off and slinging it down the hole, you're not really doing yourself any favors.

[Edit]I don't mean to suggest it's bad to just use a single anchor and sling the rope down, just consider your other options. You don't need to be rigging for rescue of doing other fancy stuff to look at some alternative methods of rigging. Serious vertical cavers should really know this stuff, even if 90% of the other cavers at 90% of your popular cave locations just use the basic method.
Last edited by NZcaver on Dec 14, 2007 9:04 pm, edited 2 times in total.
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Postby David Grimes » Dec 14, 2007 8:52 pm

I really figured simple rigging was adequate in most cases I have seen times when positioning over the entrance is necessary but like I said some seemed rather extravagant.
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Postby ian mckenzie » Dec 17, 2007 5:36 pm

wyandottecaver wrote:it all depends of course
Yup; mostly it depends on where you live. Out here, we've got hard, sharp limestone, not like the jello you've got in the SE USA. And usually a decided lack of trees at the entrances. So our definition of 'simple rigging' is quite different.
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Postby Ralph E. Powers » Dec 17, 2007 5:50 pm

Same as it is out in Utah as well. Sometimes there's a nice stout stunted cedar to rig to but other times one has to use webbing wrapped 3-pull 2 around a BFR because there are no trees. Other times a vehicle is the anchor provided one can get one close enough.

Elaborate rigging is as it's been said a matter of circumstances. But do get the training before-hand and not (just) out of a book to ensure everything is Bomb proof.

Upon reading "rigging for rescue" particularly for beginner climbers... my first thought was ... they don't belong there if they can't function a simple change-over. But then again... the rfr might not always be such a bad idea after-all.
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Postby wyandottecaver » Dec 17, 2007 7:09 pm

I have found that while I don't use it often, being able to lower climbers on a pre-rigged rack is terribly useful. Anytime someone is using a new system, or wants to "try a homemade system" thats a red flag for the rack rigging :)

As a general rule, my field "instruction" of new climbers is thus: 1) tie and climb on pre-made prussics in an easy pit less than 50' deep. 2) practice climbing and changeovers with frog system 3) rigging for dummies. basically, I stress that while 99% of your climbing may be with cams, with a pocketfull of prussics you can get yourself out of most situations.
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Postby fuzzy-hair-man » Dec 17, 2007 7:27 pm

wyandottecaver wrote:I have found that while I don't use it often, being able to lower climbers on a pre-rigged rack is terribly useful. Anytime someone is using a new system, or wants to "try a homemade system" thats a red flag for the rack rigging :)


This is a red flag to me that they should have already tried it out in a SRT practice session. In my opinion is all new or unfamiliar gear should have been practiced outside a cave where mistakes are less serious.

I agree with the rigging for rescue idea in practice for us (rebelays etc) it's less simple and in most cases is not practical.
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Postby wyandottecaver » Dec 17, 2007 7:55 pm

you are of course right fuzzy. unfortunately I can't tell you how many times I have shown up at a trip where people were using unfamiliar systems/equipment. many times only revealing this situation at the top of the pit or even at the bottom!
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Postby fuzzy-hair-man » Dec 17, 2007 8:12 pm

wyandottecaver wrote:unfortunately I can't tell you how many times I have shown up at a trip where people were using unfamiliar systems/equipment. many times only revealing this situation at the top of the pit or even at the bottom!


Too true, too true :sad: in which case yes it makes perfect sense and is a wise practice.

Fortunately for me most of the trips I lead are club trips so if someone turns up with weird gear or setups we generally gently migrate them to use the club's gear or a frog setup. If they can demonstrate that they can pass re-belays, knot crossings, change-overs and redirects easily safely then they can keep whatever setup they're using, of course by the time they've demonstrated this they have generally seen the deficiencies in their system and are migrating to a frog anyway. With our relatively short pitches there is not really much call for ropewalkers and I'm yet to see a Mitchell.

I've had some people turn up with weird or incomplete gear :rant:
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Postby Brad Tipton » Dec 17, 2007 11:31 pm

wyandottecaver wrote:you are of course right fuzzy. unfortunately I can't tell you how many times I have shown up at a trip where people were using unfamiliar systems/equipment. many times only revealing this situation at the top of the pit or even at the bottom!



Are you serious? :yikes:

I would have a freaking stroke out.
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Postby Ralph E. Powers » Dec 18, 2007 1:27 am

fuzzy-hair-man wrote:This is a red flag to me that they should have already tried it out in a SRT practice session. In my opinion is all new or unfamiliar gear should have been practiced outside a cave where mistakes are less serious.


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Postby ek » Dec 18, 2007 3:22 am

dark_storm83 wrote:Just curious how most people rig their ropes for the first descent into a cave.

What I do is one way of many, and I certainly would not represent it as necessarily the best. That said...

In caves with thick, living trees near them that can be accessed easily without falling in the hole, I usually rig of such a tree with a 2 or 3 wrap tensionless hitch, wrapped downward (so the loop knot is at the end of the lowest wrap) with the wraps free of one another, and with the loop attached to the line with a locking carabiner, with the gate locked and the gate opening facing the line going into the pit. If it is a D or offset-D carabiner, I keep the gate on the bottom, as I have found that otherwise the 'biner tends to flip and put the gate opening away from the pit line.

I put the gate opening toward the pit line so that in case it were to slips (or, in case I manage to mess up the rigging) so that the knot gets weighted, *and* it turns out to be necessary to untie it under load, the pit line would only have to be deflected to the gate opening, and not to the center of the carabiner (to flip the 'biner and then remove it). This may seem insignificant...and maybe it is. I've never had to take the load off a tensionless hitch, much less one with the knot weighted. But I've practiced doing so, and I've found it much easier when the gate opening toward the pit line.

If I have twice as much rope as I need or more and am rigging with a tensionless hitch, I usually leave half at the top. This makes it easier to pull the rope up and provides more rope to send down in case of emergency, or use in some other capacity, and (usually) makes it possible to lower someone (very carefully!) by partially untying the hitch and allowing it to slip in a controlled fashion.

When leaving rope at the top of a drop in the winter, I usually keep it in a bag to minimize the likelihood that it will get wet, freeze up, and become less useful. Otherwise, I usually throw the bag end down into the pit, because that is a lot easier and faster than flaking out the rope and more likely to keep out tangles (I don't know about anybody else but I can certainly pack a rope in a bag more properly than I can flake it out). If there is something fragile (e.g. a formation, a person) at the bottom of the drop, or it's an unknown cave, I usually take the rope down with me in a bag hanging off my descender by a tether long enough to keep it under my feet (which in a pinch can be tied with the piece of webbing that I'm not using to rig the rope, see below).

Ralph E. Powers wrote:Sometimes there's a nice stout stunted cedar to rig to but other times one has to use webbing wrapped 3-pull 2 around a BFR because there are no trees.

If the only thing you're attaching to your anchor is the pit rope, why not just tie a bowline (properly backed up) or rethreaded figure-eight around the BFR? If the anchor needs not to slide up or down on the rig point, the bowline or figure-eight could be tied on a two-wrap coil (run around the anchor point two full turns instead of one). If the top end of the rope is in use, a "double bowline" (a bowline tied on a bight of rope) could be tied.

Then that piece of webbing and carabiner could either be available for use should the need arise, or left home for convenience.

If there is no single bomber anchor point but multiple anchor points that *should* each individually be strong enough, I rig a load-sharing anchor when it is practical to do so, but know that what looks like 50%/50% might really be 99%/1% when it's being used. For example, off two bolts, I would tie a double figure eight or a double bowline. I'm not talking about any fancy self-slipping thing, but rather:
http://www.chockstone.org/TechTips/BunnyEars.htm

You've got to keep the angle between the anchor points less than 120 degrees at the absolute most, or each anchor point feels more force than you're hanging on the anchor system. *Way* less than 120 degrees is ideal. I've heard that most bolt hangers are designed to be weighted not more than 45 degrees away from the vertical (suggesting 90 degrees as a maximum angle for bolts).

Given two bolts that are vertically far apart, I might use an alpine butterfly and a figure-eight on a bight, or a directional figure-eight and a figure-eight on a bight (or really lacking rope, a long-tail bowline and a Yosemite bowline) to rig an anchor that (probably) doesn't load-share but still maintains minimal extension.

For natural anchors that are *very probably* all individually good enough (e.g. strong-looking rock outcroppings, smaller live trees near the base), I would rig a load-sharing anchor around two or more of them with a separate rope or some webbing. This makes a whole lot of sense when you see a diagram, and absolutely none by verbal description. When I find a good diagram on the web, I'll post a link. But this may be the spiderweb-like anchor type that you've seen used.

Lacking any anchor points that are individually sufficiently strong, potentially I might create my own by setting rock (or ice) protection. I've never actually encountered a caving situation where I've felt comfortable doing that. Failing that, I would probably go find another cave, or a more experienced caver for help--I don't have the knowledge, experience, or hardware to put in bolts, and I don't trust myself to correctly rig a safe dynamic load-distributing anchor.

EDIT (everything after this point added--no sense double-posting):

fuzzy-hair-man wrote:This is a red flag to me that they should have already tried it out in a SRT practice session. In my opinion is all new or unfamiliar gear should have been practiced outside a cave where mistakes are less serious.

Agreed! There is no effective technical solution to somebody else not knowing what they're doing.

I know someone who began to rappel into her first vertical cave with her rack attached to her harness by her gear loop! I can't think of any way the drop could have been rigged to prevent that... (And it is a miracle she survived.)

There is surely no substitute for knowing understanding how your gear works and being well-supervised when you're inexperienced. Still, I am interested in the idea of rigging simple drops with fixed brake lowers (e.g. tied-off racks). Sure, it wouldn't be as strong as a tensionless hitch...but in sport caving, that rarely matters. I've belayed people down ladders with Munter hitches and then tied off the hitches and rappelled on the rope. Does anybody know any reason *not* to rig with a fixed brake lower for single-person loads, besides that it requires more gear (minimally, one HMS carabiner)?
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Postby paul » Dec 18, 2007 7:41 am

FWIW, Like Ian's example, we have a definite lack of trees near cave (or mineshaft) entrances here in the UK. These are often located on farm land and the trees were removed hundreds of years ago. There are a few examples such as Jinlgling Pot or Alum Pot in Yorkshire which have convenient trees, but these are exceptions rather than the rule.

Popular caves will have resined-in P bolts at the entrance, others may have natural rock belays or Spits (12mm self-drill anchors taking 8mm bolts). Many mineshafts around my way in the Peak District (where you often get old lead mines and caves occuring in one system) will have a lid of some sort to keep livestock out and then some means of belaying to the frame for the lid.
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Postby Ralph E. Powers » Dec 18, 2007 10:22 am

ek wrote:
Ralph E. Powers wrote:Sometimes there's a nice stout stunted cedar to rig to but other times one has to use webbing wrapped 3-pull 2 around a BFR because there are no trees.

If the only thing you're attaching to your anchor is the pit rope, why not just tie a bowline (properly backed up) or rethreaded figure-eight around the BFR? If the anchor needs not to slide up or down on the rig point, the bowline or figure-eight could be tied on a two-wrap coil (run around the anchor point two full turns instead of one). If the top end of the rope is in use, a "double bowline" (a bowline tied on a bight of rope) could be tied.

1. Bowlines have been known to come undone (without back up knots... and who uses bowlines without backup knots?). So using a length of webbing with a wrap 3-pull 2 rig (waterknot for the webbing), is much more secure and holds during rescue applications so the rig doesn't have to be changed or substituted.
2. The webbing helps protect the tree against rope abrasion, thus prolonging the life of the tree which helps maintain it's "bomb-proofness.
3. There's nothing wrong with bringing extra gear. Gear for rigging and gear for (vertical) caving.
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