ANCHORING ON THE WINDLASS
Ian Nicolson
The fascinating article by Kevin Ruscoe in the previous issue of Flying Fish has a postscript called Patagonian Anchoring. In it is the phrase ‘... we also take the chain off the windlass and lead it to a cleat ...’. If only everyone did this always we would all pay smaller insurance premiums. Sadly, plenty of windlasses are not able to take the load of the anchor chain of a pitching yacht, anchored in a belligerent wind. Some windlasses have thin-walled casings which are not much tougher than toilet paper. Some have cleats on top which look like an invitation for securing the chain, but only an optimist would trust this cleat ... which, incidentally, would be far better if it was located a lot lower down.
Anchor windlasses are complex characters. They suffer from a variety of diseases. Some sheer off all their holding-down bolts. Some break around the base flange, leaving the bottom of the windlass still securely bolted down while the main body hurtles over the bow, taking the bow pulpit and stem-head roller with it. This type of windlass clearly likes company.
Few windlasses can hold together in a real blow if the chain is merely left wrapped roughly 90° around the gipsey. It’s usually the pawl axle which breaks, and this is hardly surprising as it is in single sheer and has an overhung load ... this being an engineer’s nightmare. Sometimes the pawl breaks off, normally at its weakest point, which is where it is drilled to take its axle. The engineer who originally designed the windlass doubtless made the pawl extra thick in way of the hole for the axle, but this enhancement puts the price up. So the money-men who inspect designs before they are put into production usually decide that the pawl has to be made out of a dirt-cheap piece of flat plate. But then the money-men never go to sea.
As every experienced owner knows, that favourite dictum: ‘Work is the curse of the Cruising Classes’, has been joined by a new, sadder saying: ‘Penny-pinching production is the Curse of All the Yachting Classes’. Not all windlasses have brakes on the drums, and those that do tend to suffer from corrosion, so that the brake is not always fully effective after a few months of regular dousing on the foredeck. Where a brake has its own dedicated tightening wheel, the diameter of this wheel is seldom large so the crew cannot grind the brake up brutally hard – which is what you want when the conditions are scary.
Some windlasses are guiltless and hold together in spite of being overloaded. However the securing sometimes lets them down. So-called ‘penny’ washers (about the size of a pre-decimalization penny) on the holding-down bolts, under the nuts below deck, are not good enough. What the ideal offshore cruiser has is an all-enveloping washer plate which takes in all the holding-down bolts. This is rather heavy due to its area, to be sure, but it can have a modest-size lightening hole or two cut in it. What it guarantees is that the windlass will not rip off the deck unless the bolts fail.
Of course the deck may let go ... one of the first jobs I had when I was apprenticed was sorting out the mess after the motor cruiser belonging to the band leader, Billy Cotton, broke adrift in Poole harbour one wild windy night. The windlass held and its bolts were above suspicion, however the deck tore out all round the edge. When the boat was later hauled off the shore she appeared to have an ‘open hold’ right forward.
On big yachts a chain brake is fitted, and this is clamped down tight once the correct amount of chain has been run out. It has the advantage of being low down on the deck and is traditionally designed to hold a battleship in a hurricane. Since this option is not open to many owners, two tackles, each with a chain hook on the end, are the average owner’s alternative. Once the chain has been run out, one chain hook is dropped over the chain and the tackle on the hook made fast to the starboard cleat – assuming the gipsey is on the starboard side, as it usually is when there is just one gipsey.
The second chain hook is engaged forward of the first one, then its tackle secured to the port cleat, and hauled tight. This gives two tackles sharing the anchor chain load. Finally, the chain is lifted off the windlass and made fast to the sampson post. At this stage some people slack off the tackles so that they are just there to take the strain if the sampson post fails. Others like to use the stretchiness of the tackles to absorb the jolts and the sampson post is the long-stop which handles the ‘situation’ if the tackles can’t manage.
There is a simple rule for the size of the tackles. Assuming they are four-part, (that is there are two double blocks), then the diameter of the terylene/dacron rope needs to be the same as that of the chain. For instance, an 8mm chain needs a four-part tackle of 8mm terylene – with blocks to match the strength of the rope. In practice, when a tackle fails it is usually the blocks which disintegrate, so going one size up makes sense. And of course the blocks have to be high quality, with metal side straps which have cross-sections to match the chain cross-section.
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