RRC Archives

Alan Evil wrote:
...The worst kind of non-rappelling sand packing toproping hangdogging ropehauling miscreants would barely leave a scratch on a chain by twos or fours. It's when there are thousands of them that you see the wear.

Agreed.

A virgin nylon rope would take a long time to wear down carbon steel or stainless steel links. But, when the rope is embedded with sand particles (which can hardly be avoided down here in the Red), it becomes a "lap" and can easily abrade away metal. Soft laps with hard particles are commonly used in industry to remove and polish metal.

Whether TRing or lowering, the more sand particles are rubbed across the surface of the link, the more the wear.

Heat doesn't play a roll here. If you got the steel links hot enough to remove molecules, your rope would already be a smouldering mass.

IMO, I'll stick with the rap for the most part. Back cleaning overhanging rock is the exception as long as there is quick links. I've read about how dangerous it is to rap and can't help but think of what is said in the front of most guide books. "WARNING: CLIMBING IS A SPORT WHERE YOU MAY BE SERIOUSLY INJURED OR DIE."

I think part of my opinion is based on climbing mostly trad. Much of which is old traditional areas. Some of the rings are hollow rap rings, you would never lower off those except in an emergency.

That said, just do what you need to do to be safe.

It is an understatement to say that it is hard to clean steep routes on rappel. It is impossible, even if the bottom of the rope is fixed once you remove your upper draws.........it leaves you to far out to do anything without you using ascenders pulling from the bottom.

That is why I try to use carabiners on my routes on the anchors. They can be easily repalced when wear is bad.

At rifle........a popular route like pump-o-rama or Vitamin H would go through a set of biners a year, primarily from lowering..... since most people do not top rope 50 foot overhanging routes......excpet to clean.

Steep route climbers do that frequently also. Top rope the route to clean it after previously doing it........usually for extra mileage/burn (twinkie, baremetal, etc)

i can't say for certain that i have ever seen someone rapping off a sport route in the past 9 years of climbing.

OK Listen up

abrasive wear, n - wear due to hard particles or hard protuberances forced against and moving along a solid surface.

Data to use for analysis
Climber: 175 lbs.
Rope: 7% elongation
70ft tall climb

General equation for wear = W=K·NL/H
·N: normal contact force = Climber weight of 175 lbs.
·L: sliding distance = Rope stretch once it comes tight upon fall or lower distance
·H: material hardness = assume 1 for simplicity
·K: wear coefficient = assume 1 for simplicity

TOPROPE
Typical top-rope fall generate 2gs on the climber and belayer which = 4gs on the anchor. Now assume a rope stretch of 7ft (100 ft. of rope out w/ 7% stretch). 4gs equates to 700 lbs normal contact force on the anchor. Wear = (1 x 700 x 7) / 1 = 4,900

LOWER
Typical lower = 1g if you lower in one controlled smooth lower which = 350 lbs on the anchor. However, if you stop quickly in a lower you do the same thing as a toprope. Wear = (1 x 350 x 70) /1 = 24,500

One lower is approximately 5 times worse than one toprope fall. So, if someone falls 5 times on toprope it’s as bad as one lower. Since the toproper will also be lowering it's 1.2 time worse to toprope than lower if you fell once on toprope. Not a huge difference.

Edited due to beerconfusion. Forgot to double the lower weight on the anchor.

If you find hardware in Muir Valley that shows wear, please let t_bone, j-rock, squeezendelemon, or me know asap, and it will be replaced asap. Please, save your money, and do not replace our hardware with your hardware in Muir.

If you replace or put up hardware elsewhere, we have found several excellent sources for Quick Links (also known as threaded connectors or maillons), bolts, chains and other anchoring hardware.

To answer a lot of questions directed to us about good sources for anchor hardware, I am starting a thread under the subject "Anchor hardware and sources."

Rick

Good thread. Lots of food for thought being provided by everyone.

> Are you safer rapping or lowering if you get hit by rockfall?

Are you safer rapping or lowering if YOUR PARTNER gets hit by rockfall? The rockfall that I’ve witnessed in 19 yrs of climbing has almost always been initiated by the feet or hands of the climber/rappeler. Who is more likely to get hit by rockfall, those below or you?

> Lowering is NOT THE PROBLEM with anchor wear - Top roping through the
> anchor gear is what really wears it out.

I’ll agree that one climber top roping directly from the anchors results in much more wear on the anchors than one climber simply lowering directly from the anchors, but to suggest that lowering does not contribute substantially to anchor wear is not realistic.

> It would be ridiculous to take the time to rappel if you're leaving your draws
> up and someone is going to either TR the route or lead on your gear.

It would be equally ridiculous to lower directly from the anchors (rather from your own draws) if you left the route equipped for someone else to pinkpoint.

> [Lowering seems quicker than rapping.] That way, I can quickly get on
> another route.

If it seems quicker, consider that rapping can free your partner to start getting stuff ready to move on to the next route.

> the point … is that you can always stay on belay.

Daisy chains to the anchor aside, I don’t consider myself to be “on belay” if I’m looking at groundfall regardless of whether or not a belay device is on the other end of my rope. I do think that Aenima’s tip of threading a BIGHT (not bite) and clipping a figure eight on a bight to your harness has value, but clipping the rope to you rather than tying in directly to your harness introduces additional risks (be careful not to allow the ‘biners to become side-loaded). Most risks can be mitigated as long as you are aware of the risk, have a good base of knowledge and experience, and reason through the possibilities. Experience comes through carefully exposing yourself to new situations.

> I feel more comfortable / safer lowering

I feel more comfortable laying on the floor in front of the boob tube, but that doesn’t keep me from climbing.

> I'm lazy [and selfish?]..lower away mate.

That seems to sum it up in most cases.

Regarding the neat trick that marathonmedic sites from a recent issue of Climbing magazine, it sounds good in theory, but anything that changes the direction of the loading on the bolts or anything that puts torque on hardware makes me very leery. Think this through.

I'll admit I haven't actually tried that biner trick yet. But as I understand it, the force of a fall with be on the biners clipped into the chains so the force will still be pulling in the same direction as if you were clipped to the bottom links of the chains. Running the rope through those links just makes the ends turn a bit but they're not load bearing in that situation, so I don't think it would matter. Still think it through and feel free to modify it if you need to.

As long as you are not effectively shortening each chain much, I think you are right. But if you were to clip those 'biners into the bolts, you could be radically changing the angles and magnitudes of the forces placed on the bolts. Seems like most of the chains I've encountered were too small to clip 'biners into the links (or maybe it is just my fat old 'biners...).

*Are you safer rapping or lowering if YOUR PARTNER gets hit by rockfall? The rockfall that I’ve witnessed in 19 yrs of climbing has almost always been initiated by the feet or hands of the climber/rappeler. Who is more likely to get hit by rockfall, those below or you?*

Handhold or foothold blows while you are pulling on it on lead, you fall and are airborne, hand/foothold beans your belayer on the head, knocking him/her out, he/she lets go of rope...with a grigri you get to live. With any other device, adios muchachos...also pretty easy to knock stuff off while being lowered...why people still use belay devices that don't work if you let go of the rope is beyond me...