Tag Archives: Spectra

Deadly Optimism

This utterly brilliant, ultra-sketchy Jive-Ass Anchor was photographed and submitted by Andrew McLeod, who happened upon it at one of the UK’s most popular crags (Stanage). I would like to commend Andrew right at the outset for providing exceptional photographic documentation, and delicious expository prose with his submission. Indeed, he had me at the caption of the first photo, which reads, “This was one of the most, if not the most, optimistic sling placements I have ever seen.” He was referring to this:

Sheer Luck Sling: An Optimistic Sling Placement that is barely holding on the edge of a slab of rock.

Optimistic Sling Placement

Whoa! Optimistic indeed. This would be the ‘dark side’ of optimism. It looks as though that thing is going to just slip over the edge at any moment. And this provokes an interesting bit of climbing philosophy to ponder. There is value to being a bit pessimistic about climbing. I don’t mean so grim and hopeless that you see no point in leaving your living room sofa to go out climbing. What I mean is having enough pessimism to plan and be prepared for the worst case scenario even if you always hope for the best case scenario. This is sometimes described as “protective pessimism“. It gives you a better margin of error. If you’re counting on everything to come off perfectly in order to succeed, you’re eventually going to get screwed badly–especially in as unforgiving an activity as climbing. This is what I mean by the dark side of optimism (illustrated well in the photo above).

But I digress! Let’s examine this “optimistic” anchor further, starting this time at the power point and working backwards.

Clove hitch loving power point.

A Power Point for Clove Hitch Lovers.

This is the power point. Notice that there are a lot of clove hitches attaching the rope to the carabiner. “for reasons unknown,” as Andrew notes. What the fuck are the clove hitches for exactly, I mean apart from creating a rat’s nest of clusterfuckage? Note also that the power point isn’t extended far enough to make it over the edge of the rock, so there is a spectra/dyneema sling attached. Notice that that spectra/dyneema sling is girth hitched to the carabiner, again for reasons unknown (knots and hitches weaken cordage, so this isn’t helping).  As Andrew also notes, there was more than enough rope left to extend that power point over the edge (especially if you were to remove a half a dozen of those clove hitches). The sling is unnecessary.

So just to orient you for the next pictures, here is Andrew’s handy description of where the strands run: “Left hand rope goes to sheer-luck sling [Editor’s Note: aka the Optimisitic Sling Placement], right hand rope to boulder-jam thread, centre to under-boulder gear.” Sounds delightful, no? You’ve already seen the sheer-luck sling, so let’s move onto the boulder-jam thread.

Boulder Jam Thread.

Boulder Jam Thread.

Oh hell yeah! Let’s thread a sling between two rocks pinched together! What could possibly go wrong (i.e. more dangerous optimism)? Never in the history of climbing has a sling pulled through a pinch between two rocks!

Thread the pinch!

Thread the pinch!

Here is a close up from another angle. Don’t do this, okay? This is Jive-Ass.

Let’s move on to the middle strand of rope (the short leg of the three point anchor), which Andrew described as “under-boulder gear”.

Underside of the boulder pinch.

Under-Boulder Gear.

This is a bit hard to see, so I’ll leave it to Andrew to describe: “Originally I thought this was two bits of gear and two quick-draws but looking at the photo more carefully I am beginning to think it is just one size 10 nut (the one my friend got out; the silver colour matches if it is DMM) with two opposed quick-draws. Which, given the completely non-redundant single sling over the edge, would be kind of insane, but believable…” I will add this point though: given the optimistic sling placement and the sketchy rock pinch, if this nut is well placed, then it’s really the only thing holding this mess together. That’s right. If I understand this correctly, they’re essentially top roping on a single nut placement. I hope it was well placed!

And there you have it. Luckily top roping doesn’t generate large forces. Thank’s for sharing Andrew McLeod. And to the rest of you, keep taking photos and sending them along.

Location: Stanage Edge, Derbyshire/South Yorkshire, UK

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Single Point of Failure

Single Point of Failure

Single Point of Failure

This photo comes to us compliments of Jason Brabec, who witnessed this set up just a few weeks ago in Idaho’s City of Rocks. This belay station consists of two spectra double runners girth hitched together and attached to a single large (#4 Camelot) cam placed in a crack. The belayer then extended the anchor with a length of the climbing rope, apparently to reach a more comfortable belay stance. I cropped the photo to protect the belayer’s identity (Jason didn’t know her), but you can still see the top of her helmet in the photo. According to Jason she was basically laying on her belly, with her head down, belaying her second  who was quite a way off of the deck. Jason said he couldn’t believe what he was witnessing.

There are several obvious rock climbing anchor “no-nos’ here:

  1. This is a “one point” climbing anchor consisting of a single cam in a crack in the rock. So obviously there is no redundancy. If that cam pops out, both the belayer and second fall to their deaths.
  2. The two spectra slings are girth hitched together, as we’ve seen in the past (see Hot Spectra-on-Spectra Action! and Girth Hitch Death Wish). This would be safer if the slings were connected with a carabiner. Since she extended the anchor with a length of the climbing rope anyway, she also could have just extended the climbing rope further and omitted one of those Spectra slings.

Location: City of Rocks, Idaho, USA

Hot Spectra-on-Spectra Action!

Spectra girth hitched to Spectra

Hot Spectra-on-Spectra Action

I see soft goods girth hitched to other soft goods in anchors all the time. In this case a spectra/dyneema sling is girth hitched to a spectra/nylon mix runner on a hex.

Location: Smith Rock State Park, Oregon

Spectra-on-Spectra Close Up

Spectra-on-Spectra Close Up

I’ve posted more than one “soft goods girth hitched to soft goods” anchor (see Girth Hitch Death Wish), so let’s discuss this knots issue. Any knot in cordage or webbing decreases its strength. These girth hitches reduce the strength of the slings to only 60 – 65% of their original strength. Had a carabiner been placed between the slings, there would be no knots, and the slings would still be full strength.

And how about the webbing material? HMPE (High Modulus Polyethelyne) fiber, sold under the brand names Spectra and Dyneema, is stronger than steel, light weight, and offers minimal elongation (i.e., it doesn’t stretch far before breaking). It also has a relatively low melting point: 147°C. That’s not a lot hotter than the temperature of boiling water. Friction, at enough pressure and speed, can generate enough heat to melt this fiber. An example of this pressure and speed would be if, for example, you girth hitched a Spectra runner to another Spectra runner and then had a climber fall on it. Those girth hitches would immediately tighten very tight, a great pressure and speed, and…well you get the idea. This isn’t just ‘theory’. There are examples from the field of Spectra slings melting and failing at knot points in this way, so it’s just not a good practice to tie Spectra webbing together like this.

If you care to geek out, here’s some testing from Black Diamond and the folks at Caves.org, and here’s a recent article on the pros and cons of Spectra v. Nylon from Rock and Ice. Finally, Here’s an interesting video testing knotted Dyneema from DMM. They don’t test slings girth hitched together, but the basic idea from the results are instructive just the same.

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Update: Todd Eddie offers the following link to tests from Black Diamond testing just what we’re addressing: webbing girth hitched to webbing.