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.

Practical Sailor has been independently testing and reporting on marine products for serious sailors for more than 45 years. Supported entirely by subscribers, Practical Sailor accepts no advertising or any form of compensation from manufacturers whose products we test. Testing is carried out by a team of experts from a wide range of fields including marine electronics, marine safety, marine surveying, sailboat rigging, sailmaking, engineering, ocean sailing, sailboat racing, and sailboat construction and design. This diversity of expertise allows us to carry out in-depth, objective evaluation of virtually every product available to serious sailors. Practical Sailor is edited by Darrell Nicholson, a long-time liveaboard sailor and trans-Pacific cruiser with more than three decades of experience as a marine writer, photographer, boat captain, and product tester. 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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