How to anchor

A cruising boat spends most of its time relying on either the anchor or the self-steering. Someone said that, I can’t remember who, but I do remember thinking what a sedentary life I was leading at the time as my boat spent most of its time either on a drying mooring or in a marina berth. And so she does again at the moment, but for a glorious time, she and we lived the cruising dream. We spent weeks or months in each good landfall, getting to know the local culture, and a few locals, socialising with other cruisers in the anchorage and planning our next trip, whether that would entail a day-sail, and overnighter or weeks at sea.

Once we left the English Channel, we vary rarely paid for a marina or harbour berth. Everywhere we went there was a large, sheltered anchorage where you could drop the hook for free and dinghy ashore. These anchorages were usually busy with a scruffy-looking bunch of liveaboard yachts sitting on the blue. After a while, we found we regularly came across old friends in these places – people doing a similar trip to ourselves and following a similar timetable. Once the anchor is down, the boat becomes your home and the dinghy becomes your ‘car’: You use it to visit friends on other boats and to go ashore, people can tell if you’re ‘in’ by checking for its presence (like looking in your driveway). Those who visit you tie their dinghies alongside yours at your stern, and you can tell where tonight’s party is developing by checking out all the dinghies behind someone else’s boat.

So, anchoring is not an optional extra for the cruising life, it is where a lot of the main stuff happens. Most commercial boats come from the manufacturer equipped with an anchoring system that is suitable a ‘lunch hook’: it is suitable to hold the boat in a quiet bay while you and your guests sit aboard and have lunch, before heading back to the marina before dark. This is a different usage and a different mindset to that required for long-distance, long-term liveaboard cruising. If you intend to leave the boat for hours at a time while you explore the shops, restaurants and bars ashore and if you intend to sleep soundly, night after night, without mounting any ‘anchor watch’, then you need something altogether more substantial. Add to this the absolute fact that if you spend a year or more living aboard your boat then the will be times when the wind gets up, thunderstorms pass and gales blow, wherever you are in the world. The anchor (and your seamanship, if these things happen on passage) will just have to cope; it’s no good saying, “Well, I didn’t expect that”.

How big

Unfortunately there is no simple formula for calculating the ideal anchor and chain size. Even if you can predict what dire weather may blow up, you can’t tell what the bottom and the holding will be like on that day, or whether there will be a boat behind that prevents you veering out your full length of chain, or whether meter-high waves will build up in the anchorage and make your boat snatch at the anchor while she pulls. Even calculating the forward-on windage of your boat, mast and all its rigging doesn’t count for much if she turns out to have a habit of slewing around to one side and then the other in a blow. Most boats do, and this presents side-on windage to the gale, which is far worse. Every boat I’ve seen drag its anchor has done so by not swinging onto the other tack one time in the slewing process. Staying almost beam-on to the wind they heel over and drag back through the other boats, “with all the grace of a randy elephant”, as someone else said.

There has to be some compromise, for example, there is no point in sizing your ground tackle to cope with the windage of both boats after one of these rogue ‘elephants’ has drifted down onto you and entangled her tackle in yours. On the other hand, to cope with the rest, a rule of ‘as big as possible’ might be assumed. Unfortunately, manufacturers’ recommendations are less than helpful. The majority of anchors are sold into the lunch-hook market and manufacturers compete with each other. No one wants to be recommending huge, heavy things when their competitors are offering shiny, lightweight options that claim almost supernatural technical features. If the man in the chandlery says, “This will be fine, we sell a lot of these”, try asking him what it will be like with gusts to Force 9.

Some chandleries are more clued up than others. West Marine specify a range of boat sizes for every anchor that serves the long-distance cruiser well at one end. We have a 35 lb CQR and Rusalka Mist is 28 feet on deck. It has survived everything mentioned here, including a Force 9 thunderstorm in Spain, and never dragged. West Marine recommend its use from 26 feet and upwards, and that is even more conservative. Her manufacturer’s original 25 lb model put us in the middle of West Marine’s recommended range (16 – 32 feet), which was fine for general use. Using information like this from people who have a bit of experience, and whom you trust, is about the best you can do.

Which type

Beware the yacht-club bore who has an almost religious conviction that he alone has found the perfect anchor design (and its either half the price, or double the price, of everything else on the market). With diagrams, bluster and salty tales many people have strongly-held beliefs about anchor shapes. Anything that’s heavy will hold a boat in light winds; nothing will hold a boat in a gale if it’s not dug deep into a good bottom, or hooked firmly on rock; anything will foul on a suitable obstruction. Indeed, given enough force, any anchor will bend and distort, and some will actually break.

I’m not going to tell you which is the best all-rounder. We have a 35 lb CQR, which I chose for its forged strength, its pointy, penetrating hook and its hinge, as well as its deep galvanising. Others swear by the Bruce for its ability to put a lot of force onto a lot of mud, and then there are all the others. I would avoid “this year’s revolutionary new idea”, light aluminium alloys and anything that can take your finger off while you try to stow it.

If you upgrade, don’t get rid of the old one. When you depend on anchoring, you can’t have too many. If you ever have to tie a fender to your rode, cut, and run for any reason, you will be glad that you have spare anchors and rodes so that you can come back in the morning, anchor again and sort the problems out. Have a couple of different designs. If after the fifth attempt, your main anchor won’t hold on some bottom somewhere, then changing to a different design may be just the thing.

The rode

There are still people who swear by nylon rope anchor rodes, but they are in the very small minority. When you get to a busy anchorage, we’re going to talk about finding a good spot and fitting in with everyone else. If one person has anchored to rope and all the others to chain, then swinging circles and neighborliness gets a whole lot more difficult around them. If that one person is always you, you are giving yourself an unnecessary headache everywhere you go.

Get chain that suits the oversized anchor you chose. I chose 3/8 inch chain (roughly 10 mm), whereas the boat had been supplied with 5/16 chain (roughly 8 mm). Anchors break out of the ground as soon as the pull on the chain starts to lift the shank of the anchor off the mud. Therefore the heavier the chain, the more boat-force it will absorb before disturbing the set of the anchor. Get the heaviest chain you can.

How much chain? Well, again the answer is, as much as the chain locker will comfortably hold. For us, that’s 60 meters. People have different formulae for calculating the length of chain to put out. I’m going to explain why I use 12 x √depth in a minute, but suffice to say here that 60 = 12 x √25, so it appears we can use that in 25 meters of water. We spent a few nights anchored in 20 m off the coast of Portugal, in steady 20 kn trade winds, but most yacht anchorages are 5 -10 m deep. On the other hand, when the wind pipes up, extra chain sitting in the locker is doing no good at all – let more out provided there is room behind and around for swinging room. The evening when thunderstorms in the mountains behind the town brought 45 knot (Force 9) winds across a Spanish anchorage, I let out all the chain we had, and we were one of only a handful of boats not to drag. Several boats were badly damaged and a few people were killed that night (I think they were out in the bay in a RIB, not yachties).

Don’t forget that you are going to handle all this on a windlass, so this must be calibrated chain. I know that is the most expensive, but this is going to be a major part of your cruising experience; don’t be a skin-flint.

The chain will need marking for length. I used two tins of paint, and laid it all out along the roadside at home. I borrowed a sport-teacher’s long tape measure, and put cardboard under the chain to protect the road while painting. You can get various plastic things that mean you don’t need paint, but you still need to lay it out and measure it accurately. I used one red mark, about 4 links long for 10 m, 2 red marks for 20 m, etc up to 6 red marks for 60 meters. In between these I used a single yellow mark for each of 5 m, 15 m, 25 m etc. The paint has now worn off  for 5 and 10 m, and so needs redoing sometime, but that’s not bad for 12 – 14 years.

The windlass

There is no way you are going to pull all this up by hand. The choices appear to be between a manual or an electric windlass, with either a vertical or a horizontal axis. I looked a little deeper and found that a surprising number of commercial models actually relied on a short loop of ordinary steel bicycle chain to provide the final drive to the gypsy. That put me off, so I started looking at which ones used machined bronze gear-wheels to provide the drive. It’s true that, once anchored, you will take the strain off the windlass with a snubber rope. On the other hand, while actually raising or lowing the chain, the boat will be anchored by the windlass alone. Sometime anchors need raising in a hurry at the height of a storm because the wind has veered, or because someone else has dragged and fouled it. It struck me as useless to have all that expensive heavy chain and then to rely on a piece of (probably) rusty bicycle chain for the last bit. On the the other hand, I have never heard of anybody suffering a breakage in this area, so maybe I was overcautious.

Another horror story haunted my decision making too. Somewhere I read, and I’m sure saw photographs, of a boat that had been left at anchor, with a snubber, to an electric windlass. Sometime with no one aboard, something had shorted out by itself and started the windlass, which dutifully pulled in all the chain, casting the boat adrift. Worse than this, no one told the windlass to stop, so after the anchor was in the bow roller, it carried on pulling until first it damaged the roller and fibreglass, then finally it caught fire, melting the battery and really wrecking the boat. Now, maybe that is an urban (or a seafaring?) myth, but, along with the expense, hassle and space required for an extra battery or very heavy wiring, it was enough for me. I chose a Simpson Lawrence Sea Tiger 555 manual windlass, and have never regretted it.

I should give the cons as well as the pros. Neither my partner nor I find any great hardship in pulling up the ground tackle this way. There are two gear ratios and the slower one is so powerful that Nicky has successfully raised a whole aluminium roof girder from a Caribbean seabed without any difficulty (the remains of a hurricane damaged beach-front cafe had fouled our anchor). The lack of power consumption means that we do not feel that we need the engine running and so can happily anchor under sail, and leave the same way if we choose. The fact that you are doing it means that you can raise or lower the anchor fast if there is urgency, or slow if there is leisure. This is unlike electric jobs which carry on infuriatingly at their own pace whatever the circumstances. On the other hand, the clutch/brake arrangement which is meant to control the lowering of the hook, is a bit badly designed so that there is a tendency to get ‘too fast’ or ‘jammed stopped’ as the two speeds, rather than ‘just right’ and ‘ahhh’. Lastly, just this year, after about 12 or 14 years of use, all the white paint has decided finally to come off the cast aluminium body, leaving a nasty mottled grey. I think the problem has been electric currents set up by the electrolysis of all the different metals – aluminium body, bronze gears, bronze gypsy holding zinc galvanised steel chain attached to zinc galvanised iron anchor resting on stainless steel fittings on pulpit. Perhaps if I had not left the chain around the gypsy winter and summer year in year out, it might have looked nicer for longer.

Anchoring

Finally, with all the best equipment money can buy, carefully fitted, we get to an anchorage… Very often there doesn’t seem to be any gaps, or the only spaces are in what are obviously not the best areas – too near the wall, too near the open sea. The first thing is not to rush. Tootle around the anchorage for a few minutes, having a look from this side and that. Too often, the relief of having arrived, coupled with some kind of idea that people are watching and we don’t want to look like we don’t know what we’re doing, makes us want to rush. No, have a look around, wave and say hi to a few existing residents. Have a look at the compass and see which way the wind might change if the present forecast comes true. Look at the depth sounder and do 12 x √d in your head. Add a bit for high tide later in the day and do it again. There’s no rush.

Trying to imagine what your, say, 36 m of chain will look like when out, plus guessing how all the other boats will swing when the wind changes is usually too much for me to visualise. So we pick two boats that have a bit of space behind them both, motor up until our bow is roughly between their two sterns and drop the anchor there. If you lay out the chain and find that you don’t have anybody close behind or beside you, you did OK. If you do, pick it all up again and pretend that you always have a practice run like this.

If it all looks OK for space, engage reverse gear and find a side-transit. Put on a bit of revs gently and watch the transit (try not to use another boat, they all move all the time). Your backward motion should stop. Crew on the foredeck may put a foot on chain and should feel no vibrations or jerking. If things are not right, pull it all up and repeat. Keep repeating until everything is just right.

Laying out the chain is a bit of an art. It helps if the foredeck person has an idea what the depth is before going up there. If it’s 6 m, then shortly after the 5 m mark on the chain disappears below the surface, they can imagine that the hook has reached the bottom. A glance to the side should confirm  that we are already drifting backwards. If not, hold it there until we are. Then start laying out chain until we reach about two or two and a half times the depth (12 – 15 m for 6 m deep). At this point there should be just enough for the hook to start to set. Maybe hold it there for a few seconds and see if the boat swings bow-to-wind a little. If so, good, let the rest out, roughly at the speed that we are drifting back. Having some idea that the hook may have caught and set correctly early on is a comforting thought.

When everything is settled and the hook has been dug in and tested, it is time for a snubber. Many boats have a dedicated rope for this, often with a special hook spliced into one end. I don’t like those hooks, they look to me like they are going to damage the chain link that they bear on if enough force is put on. There is always somebody wants to make a commercial opportunity out of every little need. I use an ordinary mooring warp, preferably one of the nylon ones as they have a bit of stretch should the whole anchor chain catenary pull tight, although I don’t think it ever has yet. I have a curved rope-roller one side of the forestay, and an angular roller for chain the other side, so this takes a minute to think through. Figure-of-eight one end of the mooring warp to a large foredeck cleat and pass the other end out through the stem-head rope-roller. Loop it around outside of the forestay and bring it back aboard above the anchor chain. Somewhere between the bow roller and the windlass, tie a rolling hitch around the anchor chain, with the two loops towards you, to pull up the chain in the end. Then release the brake on the windlass again and let the whole thing out until the rope takes all the strain and the chain is hanging slightly slack. Put the brake back on, just in case, and we have a locking pawl that really does prevent the windlass from turning.

Lastly, we have a stainless steel rod that goes across above the two rollers to stop both the rope and chain from jumping out. I know it’s a long-shot, but the bouncing wake of a passing fishing boat may just dislodge these one day, and without the fair lead the chain could do some damage, so I always lock this back in. It is attached by a short lanyard to the pulpit so that I don’t lose it overboard.

Safety

There are risks when handling anchoring gear. The anchor itself is heavy and you don’t want it on your foot or shin, so make sure you are well braced before trying to lift it in or out of the stem-head roller. The real accidents, though, happen between the chain and the gypsy: NEVER under any circumstances lift the chain away from the gypsy, with your fingers wrapped around the chain, when the anchor is not secured right there on the foredeck next to you. If the boat pulls and your fingers get trapped twixt chain and gypsy, they will be mangled and cut off. Don’t ever risk it. Ever.

Another issue is securing the anchor for sea and ocean passages. Many boats come with some kind of clip to keep the anchor in the bow roller. Some people buy a beautiful expensive anchor and then drill a hole in it to pass an existing metal rod through. We remove the anchor from the roller and securely lash it to sturdy hooks welded inside the pulpit for the purpose. I lash both ends twice, using two separate short ropes at each end for double security. I really don’t want it starting to come free in a deep-sea storm and either crashing a hole in the bow somewhere, or needing me to edge all the way up to the pulpit to re-secure it in a howling gale.

Lastly, the Sea Tiger 555 has a great big hawse hole through the deck, but comes with no way to block it for sea. I have a large slab of 2″ thick glass filled nylon (don’t ask, I may tell you all about why one day). I carefully made a piece that would fit quite well in the hole, with a lip so that it can’t go through. I fixed a large hook into this from below and so the anchor chain,  detached from the anchor can be hooked on here and its weight keeps the plastic lid in place. I only bother with this for long ocean passages likely to take weeks. The anchor locker drains into the main bilge, which is easy enough to pump, it’s just that the less you have that’s actively trying to sink the boat, the less you have to worry about. The foredeck definitely gets very wet on passage, and can go right under on occasions, so this is worth thinking about. I have heard that stuffing the hawse hole with rags works too, but I had the time, the tools and the raw materials once, so I did my best.

How much chain

People have very complicated formulae for the amount of chain needed – 3 times depth, 5 times depth, not just 3 times at this depth, never less than 25 m, more to be on the safe side, etc, etc. It was a while ago, and I can’t remember where I found it, but I looked into the equation for a catenary curve, which is what an anchor-chain makes half of, just at the point where it is about to lift the sank of the anchor and dislodge it. I found that the relationship between length and depth is a square-root. This is why people have all these complex rules and sub-rules to remember. Then I got lots of people’s recommendations and tried to work out what the constant would be that covers most of them. I came up with 12. So lay out chain to twelve times the square-root of the depth, 12 x √depth. This has never let me down, when combined with the other rule, “If it gets windy, spare chain sitting in the locker is doing nothing to help, and it costs nothing to put it all out”.

You don’t need a calculator to do the square roots from the helm: You already know enough fixed points: √4 = 2; √9 = 3; √16 = 4 and √25 = 5.

Depth Sq. root Chain
4 2 24
9 3 36
16 4 48
25 5 60

You can of course extrapolate other values either in your head, or by making up a little table and taping it up somewhere aboard.

Anchor buoy

I only once ever used an anchor bouy, in La Coruña in Spain, and within a week a French boat picked it up and started tying up to it, potentially casting us both adrift. It was an unusual, small, hard red ball that I had decorated with felt-tip anchor symbols and the name of the boat. It had only a thin line on it, but there’s always someone, somewhere who wants to tie up to it.

I never used one again, and never had an anchor foul anything that we couldn’t lift, secure with a rope and unhook ourselves from before dropping it back in. I did foul a fisherman anchor once, when I was a kid, by dropping it into a seabed of large granite boulders and getting it stuck between them. Luckily it was above the low-tide mark, so I just buoyed it and walked down to get it the next day at low tide. Most places have a scuba diving club and many cruising yachts carry scuba gear. I think if I ever lost an anchor again, it would be easy enough to get someone to dive to retrieve it. Maybe some money would change hands, maybe a meal out for the diver and their partner would be more fun.

Some people say that they like to see where their hook is by the buoy, others say that their buoy is fouling another part of the anchorage over which they should really have no claim. I’m more worried about people lifting it. I have seen people keep about 1 meter of floating rope attached to the front of their anchor with a bowline loop in it. The idea is that this is too short to foul anybody’s propeller, but long enough that they can dive to it themselves using just a snorkel, and pull it out if necessary. I’m not sure about this. I think that the compromise is likely to fail – either it will get in somebody’s prop one day, or be so far down, or so heavy, that free-diving won’t be possible, or do any good, on the day when it may be needed.

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2 Responses to “How to anchor”

  1. Mario Minucci Says:

    Good evening,
    sorry for errors in your language (I’m Italian), I’ve used this space for a contact by email with Mister N.Jones, about the old windvane Schwing Pilot (out of production). Many thanks for whatever help about that.
    Regards,
    Mario Minucci (South Italy).
    mario.minucci@gmail.com

    • Nigel Says:

      Hi Mario. You are right, as far as I can see, that the Schwing Pilot is not now in production. Schwing were a large company based in Herne, Germany, when I last contacted them. The Schwing Pilot was always an obscure product that they only made occasionally to order. From what I can see at http://schwing.com, they have since been bought by a Chinese corporation, and operate worldwide. I don’t know what else I can say. Maybe if you advertise, you might find someone who has a secondhand one for sale? All the best with that, Nigel.

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