Page 312 - Brion Toss - The Complete Rigger’s Apprentice
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Using less tar and adding some thinner (Solvex  with thinned tar or other wire preservative first. This
             or Xylol is good) makes a good bare-wire slush.  is one reason to use stainless steel seizing wire.
             Straight boiled linseed oil or mineral oil is less   Another hidden rust spot is under any item that
             effective but tidier, anhydrous lanolin thinned with  is lashed to served wire. Unless the service is covered
             mineral oil is also good, and I’ve recently found  with a chafe-resisting layer of leather or canvas, the
             that Marvel Mystery Oil applied generously and  lashing can cut through the service and expose the
             allowed to soak in is an excellent wire preservative.  wire.
             There are also some extremely expensive wire pre-  Swages are much trickier to inspect for cor-
             servatives developed for industry, which, if you can  rosion than a served splice; about the only way to
             find them in small amounts at bargain prices, are  tell anything’s happening inside a swage is to have
             very effective. Wear gloves and a respirator when  it crack from internal pressure or fatigue. Eva Hol-
             working with them. All preservative coatings can be  man recommends tapping swages with a tool handle
             applied with a paintbrush.                  to determine their condition. With a little practice
                It’s most convenient, of course, to slush the  you can learn to tell the hollow sound of a corroded
             rigging when the sticks are out; if they’re in place  swage from the live ring of a solid one.
             and you have to work aloft, you will find on your
             return that your deck is spattered with hundreds of  Fatigue   To Holman’s four surveying rules I would
             droplets of slush. To avoid this, bend a springline  add a fifth: stainless steel fatigues. No, this is not
             onto the anchor rode while at anchor and pay out  an all-metal army uniform. It refers to the charac-
             on the rode to form a bridle. This will put you at  teristic of alloyed steels of hardening and becoming
             right angles to the wind, so that as you slush the  brittle with age. The more heavily a piece of alloy is
             lee rigging, those spatters will hit the water instead.  stressed relative to its ultimate strength, the faster it
             Turn the boat around to slush the other side. And  will fatigue. Therefore, you’d survey lightly rigged
             don’t do this bridling procedure in a crowded har-  race boats for fatigue more carefully and sooner
             bor unless your neighbors to leeward don’t mind a  than heavily rigged cruisers. Also, the warmer the
             tarred bootstripe.                          climate, the faster stainless will fatigue, as the con-
                Bare wire is not as long-lived as served wire,  tribution of salt is enlarged.
             but a little attention will keep it from dying prema-  Fatigue reveals itself with cracks. Sometimes
             turely. Any one of the various slush recipes will do  small, “Gee-I’m-glad-I-spotted-that” cracks; some-
             for galvanized wire. I recently replaced a couple of  times “Oh-my-God-I-could-drive-a-truck-into-
             40-year-old shrouds that had been treated exclu-  that-thing-and-it’s-holding-up-the-jibstay” cracks.
             sively with zinc chromate; they were just about worn  Sometimes the cracks have a zigzag pattern, caused
             out, but a little tar or anhydrous lanolin a few years  by what is called stress corrosion. This can come
             ago would have gotten them to the half-century
             mark with ease.
                The most-often-unlooked-for place for galva-               Fatigue
             nized wire to rust is at the throat of the splice, at the   In his wonderful book, To Engineer Is Human,
             pointy end of the thimble. Even competent splicers   Henry Petroski notes that 50 to 90 percent of
             will sometimes neglect to “diaper” this spot ade-  failures in engineered objects result from fatigue.
             quately. The result will be that salt water will splash   There is no certain way, he says, to prove, non-
                                                            destructively, that a new object is free of internal
             up inside and rust the throat, while the rest of the   flaws. So engineers posit the existence of flaws
             wire stays like new under its service.         small enough to escape detection when new, then
                A wire seizing made with galvanized seizing wire   figure how soon use will increase their significance
                                                            sufficient for detection, and schedule examinations
             can rust from the inside out, even though brightly   for then.
             painted on its surface, if the wire isn’t rustproofed

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