These notes are intended to assist the climber who has already gained some knowledge of ice climbing and is fully aware of its risks but still wishes to progress further up the grades, and indeed the mountains. They are brief and not designed to be comprehensive in any way. Ultimately climbing is a dangerous sport and claims many casualties each year. One of the guiding principals of British climbing and mountaineering is that it is the individual climber is responsible for his or her own safety. If you cannot accept this then this site and probably climbing in general is unlikely to suit you. May we refer you to this very interesting site instead!
Myths, Cautions & Techniques of
Ice Screw Placement
Chris H. Harmston MSE
Comments on Ice Quality by Alex Lowe
"Good work on the screw research. Having read it and thought about the mechanics of pulls along the axis of the screw as opposed to loading such that shearing through the ice plays a role, it makes intuitive sense that a screw placed at a positive angle should indeed hold better, but only in ideal ice conditions - that's the big qualifier. Of course determining what constitutes "ideal ice conditions" is the art and essence of placing ice gear. I felt you made this clear in your article. My personal conclusion from your tests is to place screws at a positive angle when I feel the ice is 'very solid'. Obviously some rather ill defined terms in that statement! 'Very solid' will remain an intuitive assessment. But here are some attributes I associate with 'solid' ice.
1. Appearance: Ice that is clear (glassy) in appearance usually contains less air, thus having greater density. Grayish, opaque ice is often shot through with air bubbles and thus is less dense and has less ability to support a screw placed at a positive angle. (At what declining density though does positive angle yield the advantage to zero or negative angle?) The effect your ice tools have had on appearance as you've climbed toward the screw placement is also informative. Pick holes will reveal brittleness, plating and layering and other indicators that affect my assessment of ice quality.
Film on correct ice screw placement from the 2009 Black Diamond website.
Needle Sports 56 Main Street, Keswick, Cumbria, CA12 5JS, UK
Copyright © Needle Sports 2015. All rights reserved. | Site design by e-IGNiTION | E-commerce powered by Shopfront