Placement
It was once thought necessary or beneficial for ice-screws to be place horizontally or more than horizontally (with the hanger up) for optimum hold. However, it has since been found experimentally that a screw place with the tip angled up often holds as well or better. This surprising result is thought to be due to the previously underestimated role of the threads in holding the screw in place. However, horizontal placements are usually recommended. Consult the manufacturers instructions.
Some climbers use tape slings to "tie-off" long ice-screws that have not been fully screwed into the ice, to reduce the leverage of a fall, which might bend or break the screw. There is some risk that such slings may move and/or be slice by the screw's hanger. Some novel ice screws include a hanger that can be moved down the shaft, instead of using a sling. Placing a shorter screw is usually the preferred option, hence various lengths are available.
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