Tag Archives: Equipment

Jive-Ass Snow Picket

Jive-Ass Snow Picket

Jive-Ass Snow Picket

Check out this Jive-Ass, Old-Skool, homemade snow picket we found on the Eliot Glacier on the north side of Mt. Hood this weekend. It’s a beauty! We were on the glacier practicing high angle rescue techniques and this thing was just laying on the ice on one of the lower ice shelves near the start of the terminal morane.

Like most glaciers, the Eliot is retreating and melting at a rather disturbing rate. My hunch is that this Jive-Ass homemade picket was frozen up there in the glacier for a fairly decent amount of time, until it finally it melted free of its icy grave, sort of like Ötzi the Iceman, the 5,300 year old man who popped out of the Italian Alps in 1991. 

 Ötzi the Iceman (photo: Wikicommons)

Ötzi the Iceman (photo: Wikicommons)

I’m not saying this picket was buried in the ice for anything approaching that amount of time, mind you. I’m thinking maybe a decade or two. This highly speculative hypothesis is supported in some small measure by the 1970s era Chouinard Carabiner attached to it. That thing is an antique. Yvon Chouinard hasn’t sold carabiners since Chouinard Equipment Company filed for Chapter 11 bankruptcy protection in 1989, due to several product liability lawsuites, and several former employees bought the inventory and founded Black Diamond Equipment

As to the picket itself? It appears to be a rather thin aluminum tube with a hole drilled in the end. Through that hole there is a piece of steel cable formed into a loop with a metal cable crimp. Notice also that the tube is sort of bent. I hope that didn’t happen while someone was hanging from it. 

Location: Eliot Glacier, Mt. Hood, Oregon, 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.