Slicing, Dicing Abrasion Data

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stanchion hole

Photos by Drew Frye

For testing, we used the same abrasion rig we used to test sewn eyes and rope (see PS March 2015). A modified wood lathe sawed line samples back and forth (a 3/4-inch stroke) at seven cycles per second through a 10-millimeter test stanchion hole. We tested each sample to failure, effectively condensing months or years of wear into just minutes.

During some trials, we held the chafe guards stationary in the hole, allowing the line to slide inside the guard; this provided the best protection against wear. We also tested each sample against a medium-grit, aluminum oxide grindstone hole, simulating a worst-case scenario. We compared these results with our experiences with polyester line and steel cable.

To test each rope or chafe materials resistance to side-to-side cutting, we passed each material sample through a saw-cut piece of stainless steel so that it exited at a 30-degree angle; then we attached a 100-pound weight to the end. To produce the sawing motion, we swung the weight like a pendulum through 30-degree arcs.

We tested three styles of stanchion hole: rough drilled with no finishing, finished with a counter sink and polished with emery cloth, and a hole that had been finished, but then grooved by running a rigging wire though it on an oscillating abrasion machine for 20 minutes.

In both cases, the holes were prepared fresh for each sample. Typically, most of the damage came early in the test, since the hole became smoother as testing progressed.

Darrell Nicholson, editor of Practical Sailor, grew up boating on Miami’s Biscayne Bay on everything from prams to Morgan ketches. Two years out of Emory University, after a brief stint as a sportswriter, he set out from Miami aboard a 60-year-old wooden William Atkin ketch named Tosca. For 10 years, he and writer-photographer Theresa Gibbons explored the Caribbean, crossed the Pacific, and cruised Southeast Asia aboard Tosca, working along the way as journalists and documenting their adventures for various travel and sailing publications, including Cruising World, Sail, Sailing, Cruising Helmsman, and Sailing World. Upon his return to land life, Darrell became the associate editor, then senior editor at Cruising World magazine, where he worked for five years. Before taking on the editor’s position at Practical Sailor, Darrell was the editor of Offshore magazine, a boating-lifestyle magazine serving the New England area. Darrell has won multiple awards from Boating Writer’s International, including the Monk Farnham award for editorial excellence. He holds a U.S. Coast Guard 100-ton Master license and has worked as a harbor pilot and skippered a variety of commercial charter boats.

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