December 11, 2008

Stopping that chain

EVER HEARD OF a chain stopper? Not enough boaters have, apparently.

When I was managing editor of a boating magazine, I received an anguished letter from the owner of a Hans Christian 38 who almost lost his boat on a lee shore because his anchor chain kept slipping on the windlass.

It was blowing 50 knots and high seas were breaking in 50 feet of water off Isla Isabella, in Mexico's Gulf of California. A reef lay dangerously close aft.

When the skipper tried to raise his 45-pound anchor, and motor out of there, the chain just kept flying off the gypsy when the strain came on it, and even more chain would run out.

Eventually, in appalling conditions, submerged by waves sweeping over the bows, he managed to sever the chain with bolt cutters and power away to safety offshore.

What went wrong? Well, he shouldn't have been there in the first place, of course, with just himself and his wife. He had time to weigh anchor and put to sea when the wind first started blowing onshore. But it was nighttime, and he procrastinated, as most of us would have done, until the situation became pretty desperate.

In the second place, he shouldn't have expected his windlass to take the strain of a heavy boat plunging in rough seas. Windlasses are designed to break out and weigh the anchor and chain. Period.

Most anchor chains contact only one quarter of the circumference of most windlasses, so no matter how well the chain and gypsy are matched, excessive tension will strip the chain off the windlass.

The answer is a simple chain pawl or stopper. They're designed to take the enormous strain an anchor rode experiences when a boat is rearing and plunging in an unprotected anchorage. The pawl is a one-way valve, allowing chain to come inboard but not fly out again. Some pawls will fit right on the jaws of your bow roller and simply flip over when you want the chain to run out.
Chain stoppers are heavily bolted down to the foredeck in a straight line between the bow roller and the windlass.

As a matter of interest, a chain pawl can often make a windlass redundant on a boat of 30 feet in length or less. You gather the chain only when it goes slack. You don't have to bust a gut trying to hang on it when the bow rises.

This way, a reasonably fit person should be able to handle a 35-pound anchor with 5/16th inch chain in 90 feet of water without a winch.

Today's Thought
Oh hark! what means these yells and cries?
His chain some furious madman breaks —Matthew Gregory Lewis, The Maniac

“How was the movie?”
“Didn’t see it. There was a notice that said 'Under 14 not admitted.'”
“But you’re 35.”
“Yeah, I know, but I couldn’t find 13 others to go in with me.”

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