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Old 03-03-2006
GordMay GordMay is offline
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Anchor Windlass Selection

See also the Diagram at CruisersForum.com
http://cruisersforum.com/photopost//...php?photo=1525

There are a number of important criteria to be considered in selecting the correct anchor windlass (winch). These include the vessel size, displacement, windage, anchor size and rode selection. Practicalities such as locker space and depth of fall for the rode also play a part in deciding which windlass is ideal for you.

Begin by examining the depth of the anchor locker to determine the amount of 'fall' available. The fall is the vertical distance between the top of the anchor locker and the top of the anchor rode, when it is completely stored inside the locker. This measurement is important in determining whether your boat will be best suited for a vertical or horizontal windlass.

FALL: Generally chain rodes require a minimum perpendicular fall of at least 12". This is measured from the centre of the gypsy for Horizontal windlass’, and from the bottom of the locker deck for a Vertical windlass - hence a Vertical Windlass requires more cockpit locker depth.

When choosing a windlass, you face several choices. Electric or Manual, Vertical or Horizontal, what size windlass, chain size to be used, chain type, wire sizing, etc.
Manual vs Electric:

Manual vs Electric:
The advantages of a manual windlass include ease of installation, price, and less potential for things to go wrong. The advantages of an electric windlass are you don't have to use your muscles, they are quicker, and you are more likely to carry heavier ground tackle (as you don't have to lift it). Better electric windlasses have a manual operation option (in case of power failure).

Vertical vs Horizontal:
A vertical windlass has the chain gypsy and the rope capstan oriented at 90 degrees the deck, while a horizontal windlass has the gypsy and capstan parallel to the deck. Often the defining factor in choosing between vertical and horizontal is the number of anchors to be handled, the number of bow rollers, and how they line up. Often a boat with one bow roller on the center line will select a vertical windlass. A boat with two bow rollers might use a horizontal windlass.

Vertical
The advantage of a vertical windlass is its low profile, its motor and or gear box is usually under the deck (& out of the weather), and therefore the vertical units use less deck space (but use more locker space). They allow the anchor rode to come aboard at almost any horizontal angle, but the rode must enter at nearly 90 degrees to the axis of the drum. The anchor rode makes a 180 degree turn the gypsy , then a 90 down, falling into the anchor locker. They are generally harder and more costly to install and service.

Horizontal
The horizontal windlass generally offers the best performance with small or unusual locker designs. As the anchor rode enters the gypsy it makes a 90 degree turn and feeds directly down into the anchor locker. The advantages of a horizontal windlass are that they offered in a wider range of gypsy variations, are easier to install and service, and do not interfere with space in the anchor locker.
The disadvantages are that the anchor rode must travel in a direct line from the bow roller to the windlass (often necessitating the windlass to be mounted off center) which sometimes looks odd. They also take up considerably more deck space, and are totally exposed to the elements.

Size - Capacity:
The two things to consider are the Maximum Pull Capability and, the Working Load of the winch. Maximum pull (sometimes referred to as stall load) is the maximum short term or instantaneous pull of the winch. Working load is generally rated at about one third of the maximum pull, and is usually considered to be the load that the winch is pulling once the anchor is off the bottom. To determine your required maximum pull capability:
a) Maximum Pull = Total Weight of your ground tackle x 3 (or 4). Pick the nearest LARGER pulling power. The factor of three (or 4) covers the effects of windage and the speed of tidal current and includes a safety margin for unknown circumstances.
b) Use the manufacturer’s recommendations.

Chain:
Your chain rode and windlass gypsy (wildcat) must be matched (size & type).
There are three main chain types generally available in the market place. One is Proof Coil, which is not suitable for windlass applications due to the long size of the links. The other two are BBB or Triple B and HT or High Test, which are both suitable for windlasses. I generally prefer HT because it is stronger (or lighter)(it has a higher capacity per diameter/weight - increase capacity or decrease weight/size). Make sure you buy chain that is hot dipped galvanized, and that is I.S.O. Standard Chain.

NOTE:
Windlasses are not designed to hold high loads while a boat is at anchor. When the windlass is not is use and the boat is at anchor, the anchor rode should be secured using a chain stopper, or attached (via a “snubber”) to a load bearing fitting such as a cleat or bollard.

HTH,
Gord May
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