Item: Preferred knots for joining hollow braid poly rope
Title: Preferred knots for joining hollow braid poly rope
Proceedings: Proceedings of the 1998 International Snow Science Workshop, Sunriver, Oregon
Authors: Dick Chisholm
Abstract: Ski patrollers disagree about which is the most secure knot for joining two pieces of hollow braid polypropylene rope. This shiny, diamond-patterned rope, commonly called "hollow braid" and used in ski areas for closing unsafe trails, is so springy and slippery that most knots in it come untied. I have surveyed patrollers in several ski areas to find a knot that will stay tied in this rope. I handed participants two pieces of hollow braid and asked them to show me the knot they would use to join two pieces of it. Then I asked them to tell the criteria they used for selecting their knot and to explain what makes it hold tight in this rope. So far in this continuing survey, fifty patrollers have selected and tied twenty different knots. No knot was selected by a majority, but the Double Fisherman's Knot (Ashley #1415) was selected most frequently. Tests of these knots and analysis of the way their structure creates friction also show this knot to be the most suited to the task. Results of this survey can help ski patrols decide which knots to use. In addition, tying and testing knots in this slippery stuff teaches practical lessons about knot security that would be difficult to gain by other means.
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Keywords: avalanche risk management, knot security, knots for polypropylene rope, ski area management, hollow braid polypropylene rope
Digital Abstract Not Available