Anchoring: Retrofitting an electric anchor windlass yourself - here's how to do it
Johannes Erdmann
· 02.11.2023
Anchoring is wonderful, much nicer than lying close together with other yachts in the harbour. However, when the ground tackle has to be brought back on board, work is required. If it is a piece of iron that is matched to the weight of the ship - and not exactly a "coffee anchor" - even a ten-metre-long ship can weigh around 100 kilograms, which has to be hauled in by hand. If the anchor is also well dug in or the wind picks up, engine assistance is also required to pull and tear at the chain. This is because it will be almost impossible to haul in the hook by hand.
An electric anchor winch does a great job at this point. Some sailors regard it as a luxury item - but quite wrongly so. In addition to making it easier to haul in, it does one thing above all: it makes it easier to decide to re-anchor if necessary. Without a winch, the crew will be more optimistic that the dropped hook will "hold".
If an electric model is on board, there is nothing to stop you from repeating the manoeuvre at the touch of a button and releasing the hook a second time. The winch is therefore also a safety factor.
Retrofitting an anchor windlass: these models are available
The range of winches is very large. Two types are the most common: horizontal and vertical anchor winches. While the horizontal type works on deck and drops the chain into the anchor locker through a hawse, the drive of the vertical winch sits watertight below deck. Only the chain sprocket works above and transports the chain into the box.
Both models have their advantages and disadvantages. The main advantage of the horizontal winch is that it is easy to surface-mount on deck or in the anchor locker. The disadvantage is the unprotected positioning in wind and weather on the foredeck. In addition, the chain only runs about 90 degrees around the sprocket and can therefore jump off more easily than with the other design.
The vertical winch offers more holding force for the chain with a 180-degree chain rotation. The disadvantage is that the chain has to run horizontally from the winch across the deck to the anchor roller, which is not possible on ships with a high coaming - as in our example - without deflection. However, deflection rollers on deck create friction points and can act as tripping hazards. In addition, depending on the type and size of the boat, the motor and gearbox of the winch mounted below deck may protrude far into the forward cabin.
The correct dimensioning of the anchor windlass
A manual anchor winch was previously installed on the example ship, but it was getting on in years. A horizontal anchor winch was again chosen as a replacement.
Most winches can be supplied with chain nuts of different sizes and in different power ratings. The dimensioning for a ship is based on two measured variables: the power in watts and the pulling force. Two values are specified for the latter: the working load and the maximum possible force. While the winch only has to cope with the weight of the anchor and chain when hauling in, it has to exert much greater force when breaking out.
The anchor winch should also be selected so that the working tractive force still has some play in relation to the anchor and chain weight, as the chain often brings mud to the surface, which increases the weight. The peak pulling power of the winch should be well above the weight of the ground tackle.
The selected Quick Genius GP2 anchor windlass is installed on many charter boats and has proven to be less susceptible to damage. Four models between 150 and 800 watts are available. The largest model 2000 has a specified working load of 120 kilograms, but can also cope with working loads of up to 360 kilograms. The maximum pulling force when breaking out is stated as 900 kilograms, which means that the winch should be more than sufficiently dimensioned for the ten metre long ship with its 100 kilogram harness.
Connection- How much power winches consume
The power of such an anchor windlass corresponds approximately to that of a starter motor for the diesel engine. The current flow is therefore very high and the cables must be dimensioned accordingly.
A current flow of 96 amps is specified for the Quick Genius GP2 when operating under working load. This means that a cable cross-section of 35 square millimetres is required, which is laid from the foredeck to the engine room. It is not advisable to feed the windlass directly from the consumer battery - it is usually better to start the diesel engine in addition, which generates power through the alternator.
The alternator usually installed in a boat diesel provides around 70 to 80 amps of charging current, which is not quite enough for the winch to operate. The consumer battery is therefore used as a buffer. It can happen that the light in the saloon starts to flicker when the winch is in operation. To prevent this, it is advisable to install a separate battery for the anchor winch, ideally in the foredeck.
The automatic safety catch for the winch should be installed in the foredeck where it is easily accessible. After fitting a remote control or two recessed control buttons in the deck, nothing stands in the way of relaxed anchoring pleasure.
