How to Choose the Right Anchor Windlass for your Vessel

There are a number of important criteria you should consider when selecting an anchor windlass for your boat. These include vessel size, anchor size, chain size, and vessel displacement.  You also need to bear in mind practicalities such as available locker space and the depth of fall for the anchor chain.
 
1. What is the weight of your anchor, and the size and weight of your anchor chain? 
The first consideration should be the weight of your anchor, and the subsequent size and weight of the anchor chain or rope you intend to use with the anchor.

For guidance on selecting the right sized anchor and chain for your vessel see How to Size Your Anchor and Chain
 
2. What technical requirements do you need for your windlass?
Remember, an anchor windlass is designed to do one thing – to haul up an anchor chain with an anchor on the end. They are NOT designed to haul the boat forwards over the anchor first!
 
So although the weight of your vessel is important, this is only in relation to the size of your anchor and chain.
 
What are Maximum Pull, Maximum Lift and Working Load?
 
The only meaningful way to rate anchor windlass performance is by looking at what they will lift. The things to consider are the Maximum Pull, Maximum Lift and the Working Load of the windlass.
 
The Maximum Pull is the maximum short term or instantaneous pull of the winch. For example, the pull required to break the anchor out of the sea bottom.
 
The Maximum Lift is the typical continuouse load the windlass can pull during normal operations. This is usually about half the Maximum Pull of the windlass.
 
The Working Load is generally considered to be the load that the winch is pulling once the anchor is off the sea bottom, ie the total weight of the anchor and chain
 
To determine your own Working Load you should use the following calculation.
 
Add up the total weight of the ‘ground tackle’ ie, Anchor + Chain + Rope
 
For example: 20kg Anchor + 30m of 10mm Chain (69kg) = 89kg
 
Therefore your Working Load would be: 89kg
 
Most manufacturers safety guidelines specify that the Maximum Lift capacity of your windlass should not be less than 3 x times the Working Load.
 
Therefore in this situation, the Maximum Lift of the windlass required is 3 x 89kg = 267kg
 
What Motor Wattage do you Need?
 
The wattage of the motor is the measurement of its power.  The power of the motor, in combination with the mechanical assistance in the gear box, are what determine the Working Load and Maximum Pull of the windlass.
 
Clearly, the more powerful the motor, the greater the Maximum Pull. However, this would then require more power from your batteries, thicker battery cabling and bigger circuit breakers which are not only additional costs, but the extra power requirements on smaller sailing vessels can sometimes be a real concern.
 
It is therefore important NOT to just look at the wattage of the motor, but to check the Maximum Pull and compare this to your specific lifting requirements.
 
You may find that a slightly smaller wattage model will still more than meet your needs.
 
To see the range windlass and anchoring products and accessories available for leisure and commercial vessels, click here or for further technical advice, contact the Safety Marine technical team on advice@safety-marine.co.uk or call +44 (0)2380 226300.

 

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