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Old 07-24-2012
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Re: Let's talk about anchors some more

From my perspective, these kinds of discussions boil down to acceptable level of risk. When I started thinking again about anchors and more specifically, the so-called 'next generation anchors', I had hoped that these new anchor designs might really be more efficient designs, by which I mean greater holding power and reliability for a given weight. Since I typically sail on and off the anchor, and often single-hand, I want an reliable anchor that I can also handle easily.

When I began to evaluate the so-called 'next generation anchors', I found that they had to be wildly heavier than the anchors that I had been using. I concluded that if they need that much weight to generate adequate holding for a boat of my boat's size and weight, it seemed like these newer designed anchors must be a comparatively inefficient designs compared to the WW II era designs that I currently use.

To put that statement into perspective, my current ground tackle consists of a primary anchor, which is a Danforth 13 lb Deepset, my Storm anchor, which is a Danforth 20 lb hi-tensile, and I have a 21 lb Fortress FX 37 as a back up. A next gen anchor would be closer to 35-45 lbs.

I can handle my current anchors without a windlass, they fit through the bow pulpit (except the fortress), so they can be stowed securely within their assigned lockers when stowed under sail, the Fortress being partially knocked down.

In fairness, in a conversation with one of the ‘next gen anchor’ manufacturers, it became clear that these new anchors are designed and have published holding numbers which are based on a higher margin of safety in their worst holding conditions, which coincidentally is the predominant bottom condition around here.

But even so, it seems to me, it would make no sense to increase the weight of my anchors when my current compliment of anchors are 1/2 to 2/3rds the weight of these newer and are still only rated for a boat of my size and weight. Especially since my current anchors all hold well in whatever bottom that I have tried them on (soft mud, sand, hard clay), except early spring leaves, and even there they pretty well matched the heavier anchors on friends' boats around me. My 13 lb deepset Danforth with a 20 lb kellet shackled to 40 feet of chain and a couple hundred feet of nylon rode survived the 60 knot gusts of a partially spent hurricane (albeit in a moderately sheltered river) without dragging.

At some level, even discounting for the larger safety factors, if the numbers are even close to right for my boat, there is a part of me that feels like these new anchors should more accurately be called "the Generation Before Last Anchors", since they have seemingly gone so far backward in efficiency.

And the idea of adding a windlass or worse yet trying to handle a 35 or 45 lb anchor without one, is really not something that I visualize doing, which is mostly about being 62 years old and not getting any younger and the purposely simple forms of cruising that I tend to do.

For years I have been thinking about anchor design, and more specifically thinking about what my ideal anchor would look like. I would call this the perfect coastal cruiser anchor rather than the perfect world cruiser anchor. My ideal anchor would be a mix of metals to keep weight down. My thought is that that portions of the anchor need to be abrasion resistant and hold a reasonably sharp edge, while other parts of the anchor only need to be strong enough to hold in the bottom.

If I were designing my "ideal anchor" it would have a steel or stainless steel frame. That frame would include a removable and replaceable tip or snout, which would be reasonably sharp, and hardened to enter the bottom. The snout would form the leading edge of anchor in contact with the bottom and would be mounted at the end of a "keel" which would be an integral part of the frame.

The Keel would be curved so that the snout was aimed downward in order to pull the flukes into the bottom. The back end of the keel would turn slightly downward and have a flat area that behaved like the equivalent of a Fortress 'mud palm'. The keel would also serve to stiffen and weight the flukes.

From the back of the keel, the rest of the steel frame portion of the anchor would curve back on itself and attach to the tiller bar (shaft) where the rode (and recovery penant) would be attached.

The flukes and roll bar would then be aluminum to keep the weight a little more managable and to help concentrate the weight lower in the anchor where it is needed. If the flukes are aluminum, they can have a larger fluke area than if they were steel, and that would mean better holding in soft mud and sugar sand. The roll bar could be tubular for greater stiffness to weight, and would be configured to act as a strut stiffening the edges of the flukes. It would also be nice if the anchor could quickly be broken down and laid flat for storage in a locker on a long passage.

I know that there are issues about dissimilar metals and stainless steel's performance under water which would have to be considered in the design. I also know there is a bias in the yachting community against anchors which can be disassembled, but that is mostly amongst the recent 'world cruiser mindset" community. Historically anchors were designed to fold and no one complained.
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Curmudgeon at Large- and rhinestone in the rough, sailing my Farr 11.6 on the Chesapeake Bay and part-time purveyor of marine supplies

Last edited by Jeff_H; 07-24-2012 at 12:32 PM.
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