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If you want your anchor to hold in a blow, only one thing really matters: Scope.  Scope is the ratio of water depth to anchor line length.  It’s a trig problem.  At wind speed of thirty knots or more, even the heaviest chain rode is pulled as tight as a guitar string.  Scope of less than six or seven to one just lifts the anchor out of the sand or mud.  Scope of more than eight or ten doesn’t help much, because you’re already pulling pretty flat.  Draw yourself a picture.

What a lot of people get wrong is that scope is figured from where the anchor attaches to the boat.  Since our bow roller is about six feet off the water, that means we need to add 6’x6=36 feet of chain, plus 6x(Water depth) when we anchor.  More chain means more swing radius means more chance for mayhem.

So we added a 1/2″ U-Bolt to the Bright Water pointy end.

Trailer Eye
Martin and I discuss how much easier it will be to load Bright Water onto the trailer.

Then we tied 20′ of 1/2 nylon line to the bow eye.

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We lead the nylon rope up through the bow eye and attach it to the chain with a tautline hitch.  It’s not trivial to remember which way the load goes and how the knot flows.  We throw a little safety half-hitch around the standing lead.

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Once we pay out another 25′ of chain, the load goes into the nylon line.  It acts as an elastic snubber as well as reduces our swing radius.  A standard snatch hook on deck is our secondary attachment.  If the nylon line breaks there will be a loud noise and we’ll go see what happened before things get too interesting.

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Here’s the whole thing working away in 30 kts. sustained in front of the Soggy Peso bar in San Carlos.  Another benefit is that the long snubber keeps the bow/V-berth a little quieter by isolating the chain/anchor noises.

There’s not much of a backing plate on the bow eye, but the glass is over 1-1/2″ thick. I’m not too worried about it pulling through.

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