Tuesday, March 08, 2011

Interesting reading

I tend to geek out on gear pretty heavily, especially when there is some evidence to work with.

Reading and thinking on gear is, to me, important. I find fewer and fewer systems that work in all situations; understanding how things actually work and adjusting systems to the best of your ability is better than simply memorizing one tactic for all situations. But if you get it wrong and your improvised approach is wrong then of course yer gonna die... When I started climbing I wanted to know how strong the gear was, how much it could hold in a perfect crack, etc. etc. Now I'm more interested in the limitations of my gear; in what way does it fail? In what "unusual" situations will it simply not work (a cam won't generally work well in a crack that's even slightly icy, dry and aerated ice is bad for screws...)? The "worst-case" is more relevant than the "best case" for understanding potentially lethal situations. Put another way, understanding the limits of the gear defines the safe operating zone. A piece of gear may hold "4,000 pounds" on the store shelf, but not if the person using it places it wrong... Obvious maybe, but it's a mental approach that works for me.

A while back there was a big debate about equalizing anchors, and I wrote about that here and here.

The very short version of my take on equalizing anchor points is that, even in a perfect world with all forces as organized as possible, individual pieces don't end up very well equalized. One bomber piece and preferably two or more is critical. I just re-read an article on this from strikerescue.com,Multi_point pre_equalized anchors.pdf [396.21KB]

Lots of interesting reading on that page, including a PDF on "Dynamic Shock Load Evaluation of Ice Screws_Final.pdf "

My favorite quote from the ice screw article is this: "Short (“stubbie”) screws when placed in good ice provide a significant amount of protection that was quite unexpected and equivalent to that of rock gear when placed at ≥+10º but ≤+30º. By showing this, we have validated the concept of what angle ice screws should be placed in vertical waterfall ice as previously studied by Luebben and Harmston. While poor screw placement is always a possibility, poor ice screw placement is as weak as “rattly” rock gear. The analogy can be made that poor ice screw placement is similar to just throwing your rock climbing rack on top of the rock, clipping your rope to it and jumping off the cliff, only to hope that the gear somehow miraculously catches on something and holds your fall. Proper protection placement is crucial."

Happy reading.