Tubular Ice Screws

Depending on the quality of the ice, a well-placed tubular screw will hold from two thousand to five thousand pounds, providing excellent protection. In rotten ice, screws hold very little. Obviously, longer screws with larger diameters and deeper threads will hold better in snow-ice and rotten ice. In solid water ice, long screws are unnecessary, In practice, 90 percent of the time you can get by with screws eight to

On WH npproodwi ami low-angl» smew and ke, lelescttpk ski poles ere «we fwKtiead thou on kt □*« tor assisting Ma««. Hwy are Kght-w eight and can easily be stowed an the pack when not In use. (Photo: Ian Tankman)

On WH npproodwi ami low-angl» smew and ke, lelescttpk ski poles ere «we fwKtiead thou on kt □*« tor assisting Ma««. Hwy are Kght-w eight and can easily be stowed an the pack when not In use. (Photo: Ian Tankman)

ten inches long. For very thin ice, thread a few of your screws through the tight openings sewn into the ends of quickdraw-type runners. As soon as the screw touches rock, it is a simple matter to wind this runner down the threads to create an excellent tie-off at the ice surface. This precludes the need to carry shorter screws and allows the use of screws in series, as recommended for thin ice in the technique section of this book.

One problem with tubular screws is that the core of ice tends to freeze to the inside wall of the screw, An ice-filled tube cannot be placed again until the ice has been removed, which can be extremely difficult unless the screw design addresses this problem, Several effective solutions have been discovered. A differential inside diameter forces the ice through a slightly smaller opening at the tip, so it can be shaken out the back. Several of the very finely machined stainless steel or chrome-moly screws now on the market have such aggressive cutting teeth that the ice core is pulverized as it is forced into the tube; these screws can usually be cleared by tapping them against the head of a tool.

lie Prions

The new generation of sharply machined ice screws arc so easily ptaccd that they have largely obviated the need for ice pitons. However, pound-in protection is still occasionally useful. Ice pitons come in two main styles. Hook-type pitons have a design similar to the pick of an ice tool. Although their solid cross section tends to fracture brittle ice quite badly, they can often be fitted rapidy into a pick hole in a weakness between icicles, or slammed home for quick, temporary protection. While these protection devices often can be removed by pulling up and out on the carabiner, sometimes they must be chopped out by the second.

For hard-ice conditions, the pound-in, screw-out tube piton (commonly known as a Snarg) offers superior holding power compared with the hook styles of ice protection. A full-length slot from the rear of the tube to within about half an inch of the tip allows mechanical clearing of the ice core with the pick of a hand tool.

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