Anchors & Anchoring Updated

Observations & Options

Anchors: There is so much legend and hype associated with anchors, we’re not going to feed it. We can see differences among the major categories, but nuances within them appear to be based on anecdote and marketing hype more than anything else. We now carry a 25 kg Spade and a 20 kg Bruce on the bow roller. The Bruce has now been moved to the bow locker as it didn’t stow well next to the Spade.

We have three fluke style anchors stowed below — a big one (Fortress 37) for kedging, a smaller Danforth HT, to keep the stern from swinging in tight confines, and a 5lb Commando for the dinghy.

We have the following experience.

In 8 years with our 23 and 18 foot sailboats we used a Danforth and never dragged.

In 15 years, with our 29 footer, we used a 10 kg CQR and dragged once when we anchored by unknowingly hooking a tree limb instead of mud (believe me this was not water one would dive in to check the hook–we found out about the tree from locals later). When the anchor chewed through the limb, it took 80 yards of drag to re-set which used up all but two yards before we would have clipped a boat.

For 8 years we anchored our Freedom 40 catketch with a 20 kg Bruce and never failed to set nor dragged.

In 2008, we dragged with the 25 kg Delta when it failed to right itself on a very hard bar (shell?) in the Bells River, FL. It took three tries in three places to get a firm set.

In 2009, we had a repeat performance with the Delta in the Wye River. We switched to the Bruce, and it dragged in the same location.

In 2011 and 2012, the Delta failed to set at least four times and broke free from clean sand and took about fifty feet to barely reset in turtle grass.

These episodes are included in 1000-1100 anchorings in sand, shell, dead coral, marl, clay and grass bottoms. This is not to say we are experts, but rather the right equipment used properly is pretty reliable — but we still set anchor watches and have an anchor alarm when conditions warrant. [Conditions warrant when there will be a current reversal — not matter what the wind and waves are up to. Recently, when the current reversed, the chain looped on something, and we ended up hovering directly over the anchor for a full flood. Fortunately on the ebb I was able to use the rudder against current to ensure the chain unlooped rather than completing a problematic 360 wrap. The anchor had a trip float attached for this anchorage.]

But technology moves on, and we have been convinced the Delta is not the “right equipment”

We have zero experience with the new 55 kg Spade. We hope to report performance at least as good as what others have reported for it.

We now have a season of use with the Spade in Ga, FL, and the Bahamas. We regret having waited to acquire it!

Anchor Rodes: We have just replaced our all chain principal rode (extended with a lot of very seldom deployed nylon), ~½ chain and ½ nylon for a second anchor, and essentially all nylon with just enough chain for chafe protection for kedging.

We sometimes use an anchor float if we can be reasonably sure no one will use it to pull the anchor up out of curiosity or spite. We anchor with 4:1 — 7:1 scope 98% of the time. There are so many variables, we discuss it every time we anchor – lest habit put us aground.

Proper chain deployment is a function of water depth and the height of the anchor roller off the water. So six ft of water (our very much absolute minimum low tide on a soft bottom number) plus five feet of roller height adds to 11 feet. With our preferred scope multiplier of five, this means we won’t ever anchor, at that scope, with less than 55 ft of chain. Since we measure in 10 ft increments, this means the first 60 feet are marked with red (OK, hot pink) cable ties.

The ties are placed around the intersection of links where the anchor windlass wildcat (gypsy) can’t abrade or cut them, and they are left untrimmed to show up better. [We also keep a supply of ties in the anchor locker so missing ones can be replaced on deployment or retrieval. Another reason not to just use paint.]

The next 60 ft are marked with blue, and the rest after that with orange. The last marker — warning it is just nine feet to the rope-chain splice is pinkblueorangebluepink. A single yellow tie is added at 50, 100, and 150 feet because we like to do an anchor set engine back-down at those lengths and our final deployment length.

Obviously the pink and orange are sections are “warning” sections. The blue sort of fits our preferred range of water depth — nine to fifteen feet.

It works for us.

*
010 pink x
020 pink xx
030 pink xxx
040 pink xxxx
050 pink xxxxx + yellow x
060 pink xxxxxx
070 blue x
080 blue xx
090 blue xxx
100 blue xxxx + yellow x
110 blue xxxxx
120 blue xxxxxx
130 orange x
140 orange xx
150 orange xxx + yellow x
160 orange xxxx
170 pinkblueorangebluepink xxxxx

One thing to consider about painting chain is some locations have made it a misdemeanor for people under 18 to have spray paint in their possession.

Windlass(es): This is our second 10-11 ton boat with a windlass. Both have been electric with manual back up. Our first was a horizontal axle, our second, vertical. Both have had a working load of 100kg (or about a 7:1 stall the motor safety factor). Both were 1000 Watt units. Since the heaviest ground tackle we might deploy would be 20 kg (anchor 1) + 25 kg (anchor 2 in tandem) + 125 kg (250 feet of 5/16 chain) = 170 kg (375 lb) we could clearly bring it all in hanging from a dead drop off the bow (blown off soundings with all tackle out) provided we did so in pulses with the engine running to keep the batteries happy. We looked at improving this and the cost and weight of the necessary windlass (2000 Watt) couldn’t be justified. The next step up to 1200 Watts didn’t offer enough improvement for the cost. If we have to kedge off, we’ll be getting out a tackle.

Snubbers: For us, a suitable snubber doesn’t chafe the chain where it attaches. It shouldn’t require contortions to attach or remove. It shouldn’t work better on one tack than the other (nor interfere with our rod bobstay). It should relieve the shock loads on the hardware that secures the rode (never the windlass). For this reason we use a 20 foot, one-leg nylon line snubber with a bungee device attached such that it doesn’t end up underwater when deployed. We don’t attach (shackle or snap) the bungee to the chain because we don’t want it impeding retrieval. We tie the snubber to the chain with a length of sacrificial line and a non-jamming rolling hitch which can be slashed with a knife if untying would take too long. We also leave a foot of “tail” on the running end from the rolling hitch to facilitate breaking the knot back if it jams. We lead the snubber line through the anchor roller with lots of chafe protection to keep it clear of the bobstay. We usually only have problems if there is a tidal current that skews the boat’s relationship to the rode.

Note: Keep in mind, however, nylon line was never engineered to be used as a rubber band. The elastic properties of nylon can be an unintended benefit, but they are also its Achilles heel.
Marine nylon line at a max safe working load, stretches 6-10%. For a 20 ft snubber, this is only 16-24 inches of stretch assuming the line is sized as if it were a rope rode. Likewise, when the line is stretched this much, it has stored potential energy equal to that working load. When it lets go from over-heating or chafe (or even incidental nicking) it can damage equipment or maim crew — for a 1/2 line the energy can approach 1000 foot pounds at the point of failure.

In 1979, we had a 10 foot, 1/2 inch line stretched just over a foot let go in a 55 knot gust. It broke our man-overboard pole. A doctor sailing friend said the fibreglass pole approximated, in strength, one of the lower bones in an adult arm. A rubber snubber stores this energy in a way that should it fail, fails less aggressively in addition to reducing heat inducing cyclic loads on the line. Before including the rubber snubber, we tossed our nylon snubber’s in a dumpster twice a season.

Note: A note on handling a chain. One should always treat chain as if it is under load. Usually the weight of the deployed rode itself is enough load to seriously damage a hand caught twixt it and a hard place — if it suddenly tensions one can have tons of force pressing it into and through anything soft — people-parts for instance. If the chain load cannot be relieved, that something softer will have to be cut free. When logging in Texas decades ago, I was taught to throw a line/chain under the chain under tension and lift it with the bight of the line/chain (often with a piece of pipe or a branch as a handle). The line has to be handy and the practice has to be a habit. But I have seen a mangled hand or three over the years that made me a firm believer.

Anchor Lights: The conventional approach to anchor lights  doesn’t offer the anchored boat much protection or the night time mariner much information.  Lights at the masthead get lost in the stars, particularly the new cool white LED ones. We have mistaken an incandescent one for a landing aircraft.  If they are far enough away to be in one’s horizontal field of view, they are frequently lost in shore lights.  We anchor with two and sometimes three anchor lights (keeping in mind the Colregs requirement not to confuse the situation with deck lights).  We have  a cool white LED at the masthead.  We hang a Bebi-Electronics “Beka Kaukaua” combined anchor and cockpit light from the boom so it functions as an anchor light and a deck light.  The twilight photo above does not do this light justice, in the dark, it is blinding. If we have the enclosure up, we have another cool white LED we hang inside to make up for any blockage of the Beka. [Unfortunately Bebi has been driven out of business. A similar light is available from Frankenbebi.]

ACCOMMODATION SPACES
ANCHORS & ANCHORING
BOAT CANVAS & HATCHES & PORTS
COMMUNICATIONS & NAVIGATION & COMPUTING
DAVITS & CRANE
FENDERS & LIFELINES
GOING ALOFT
POWER
SAFETY GEAR
SAILS & SAIL HANDLING

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