Anchor Windlass types, operation & function
Before you choose a windlass you should become acquainted with their operation and function. By doing this it becomes much easier to choose the best windlass for your boat.
There are 3 phases of Windlass operation;
- Sitting At anchor
There are two options for using a windlass for anchor deployment, power down and freefall. Not all windlasses have power down but they will have freefall instead. Both of these video links demonstrate how each works.
Freefall can be 6 times faster than power down. Most Windlasses can be operated in a free-fall mode by manually loosening the clutch, which lets the gypsy spin freely. Electric windlass with freefall have an option for a switch at the helm station which allows you to singlehanded drop the anchor in your desired location. Freefall can get pretty wild as this video demonstrates so try it first in shallow water as the chain speed may get too fast in deep water.
After you have successfully deployed the anchor and it has set, you need to use a chain stopper to isolate the load from the Windlass. Typically windlasses are rated for 3 or 4 times the weight of the ground tackle and not enough to handle larger loads generated in strong winds and waves.
To soften the load or shock load, from wind and waves, on the chain stopper and boat, use a chain snubber or an anchor kellet. Both of these devices will make life at anchor much smoother and enjoyable.
Anchor retrieval is the most taxing on the Windlass. Just turning on the windlass and using it to pull you to the anchor is asking for trouble.
First step to proper anchor recovery is to turn on the boats propulsion engine. Next slowly motor up to the anchor (image 2) thereby relieving the load on the chain allowing you to pull in the slack. Once the boat is over the anchor (image 3) put the engine in neutral and hold position.
Now raise the anchor vertically until its safe on the bow roller. Pulling the anchor vertically or even slightly ahead helps overturn the anchor and break it free. My Father ex Royal Navy told me "When a ship weighs anchor, the Captain eases the ship forward until the officer in the bow signals "straight up and down".
Loading anchor and chain onto windlass Video Typical anchor retrieval speeds are around 30ft/minute at around 200lb loading, higher loads will cause a slower anchor retrieval rate.
Not recommended. The most common mistake, when raising the anchor is to pull the boat up to the anchor with the Windlass. This technique will actually dig the anchor in further and will put great strain on the Windlass motor which it is not designed for. By motoring up to the anchor and pulling in the slack as you go, you will get to the anchor break out point with the chain vertical which helps break the anchor free.
Power Consumption; The other reason to motor up to the anchor is to keep the battery voltage from dropping too low. The boats engine alternator supplies the battery bank with power while the windlass is in operation. The windlass should never be used without motoring, the voltage drop can be severe so that a drop in windlass power occurs after only a few minutes.
Windlass Loads; The load on the Windlass will steadily increase as the tension in the ground tackle increases. Just before the anchor breaks free the Windlass sustains its maximum current draw and may be as high as 2-3 times the rated current. If the anchor becomes fouled take the load on the chain-stopper and use the boat to break it loose and then resume retrieval. Once the anchor has broken out, the windlass hauls the anchor vertically back to the boat.
Probably the most important part of the Windlass is the gypsy or wildcat. The gypsy is the wheel which has contact with the rode or chain. In most boats you will need to handle both rope and chain. This picture shows the gypsy.
Gypsies can be chain only, rode only or chain and rode combinations.
This picture of a Lewmar Vertical Windlass clearly showing the chain riding on the gypsy. The optional Capstan is seen on top.
Many drive systems use a shaft to engage the Gypsy by way of a clutch. The clutch allows quicker anchor deployment, faster than a power down system. The clutch does add cost over the power down only system.
It is very important to match the gypsy with the correct chain. Not doing this will lead to fouling and chain overrides. If you already have a chain and rode combination talk to the windlass manufacturer dealer for selecting the correct gypsy.
Windlasses come in two types vertical or horizontal. The type you use will depend on the layout of the foredeck, anchor locker and ground tackle. Vertical winches let you pull the anchor line from the side of the windlass, letting you see over the side and the anchor. Horizontal windlasses only let you pull the line from behind the windlass.
Vertical or Capstan Windlass
The most common type is the vertical Windlass, think old Capstan on the sailing ships of the 1800s. But instead of a bunch of sailors pushing turning it you can have the modern convenience of a small motor. Vertical winches have the option of low profile or Capstan. Vertical with Capstan shown
The vertical axis allows the motor, if electric, to be housed below deck. The vertical windlass needs more fall than the horizontal. 18 inches minimum is recommended for a vertical windlass. Fall is the distance under the deck inside the anchor locker . Fall is needed so the chains gravity helps it to fall to the bottom of the locker. The vertical windlass takes up less deck space than a horizontal windlass, is cheaper than most horizontal models, and has 180 degrees of chain grip.
Since the gypsy does not have gravity on its side vertical windlasses need a chain stripper. If this is not working properly the chain will not drop down into the anchor locker.
With a horizontal axis windlass you can have two drums/gypsies and use one windlass for two separate anchors. All of Windlass mechanism is above deck.
The horizontal windlass needs less fall than the vertical. 12 inches minimum is recommended for a horizontal windlass.
Two drums aligned to bow roller. 90 degrees of chain grip
Tail the anchor line standing up behind the windlass
The advantages of a manual windlass include ease of installation, price, and less potential for things to go wrong.
Lofrans Manual Horizontal Windlass lets you stand and pump the handle, saving energy. You can get a decent manual windlass for under $800.
What you see is what you get, not motors or wiring.
The advantages of an electric windlass are ease of use. You can use the remote controls or foot buttons while steering and motoring up to the anchor.
The most popular windlasses on the market are electric. They are easy to set up and available in many configurations. You will need to produce enough power to keep up the batteries to run the windlass.
Some electric windlasses also offer a power control for dropping the anchor with an electronic brake to stop it. Most electric windlasses have manual option for raising the anchor as back up for a power interruption or motor failure.
There are more options such as the remote windlass control head and foot push buttons.
Larger yachts have hydraulically operated Windlasses. These work best by taking advantage of the yachts hydraulic systems.
Sizing a Windlasses
Match to ground tackle
After choosing a windlass we need to calculate the size. Windlasses are sized by the rated pull.
Size your windlass by matching the rated pull to the weight of your ground tackle; The rule of thumb is to take the total weight of your ground tackle (chain, rode and anchor) and then multiply it by 3 or 4. This is the safety factor and is recommended so that the windlass will stand up to high drag on the windlass in extreme conditions like sitting at anchor in a storm, and anchor recovery.
Lets say your ground tackle weighs 45lbs. Multiply that by 4 and you have 180lbs. You should now look for a windlass with a rated pull of at least 180 lbs.
Any boat using a windlass should also be equipped with a chain stopper. The chain stopper or anchor lock is needed to stop straining the windlass. The chain stopper can be used to help break the anchor out if it is stuck.
It can also be used to hold the anchor in the bow roller while under way. Load can be transferred to the stopper once the anchor is completely up, and the tension eased from the windlass. When preparing to drop anchor, simply snug up the anchor rode in the windlass and release the chain stop so the chain is free to run.
If you use chain for your anchors ground tackle, you will find the chain does not absorb shock loads. Instead the anchor chain will pull sharply on the bow roller and transfer the jerkiness to the anchor point and hence the boat.
To offset this use a chain snubber. The chain snubber softens motion at anchor and it reduces the high loads that lying at anchor can produce.
Chain Locker design / layout
The chain locker should be suitable sized to handle the boats ground tackle, with enough fall below deck to allow the chain or rode to spread evenly.
Chain locker drainage should be thought out. A false bottom in the locker above the waterline lets you ad a scupper to drain the water overboard.
Chain lockers are best deep and narrow. Wide and shallow chain lockers cause problems. When reeling the chain in it tends to pile up into a small mountain. A deep locker stops the chain piling up close to the deck.
An anchor windlass can save you time and energy in setting and recovering an anchor. Once you have decided on the windlass you will need to install it. There are several steps to this, which are important.
Make sure there is enough locker space under the windlass for the chain to fall and spread out. Make sure the locker has proper drainage and ventilation. An unventilated locker leads to mildew and odors.
If you are using electric power the battery cable size is important. Larger boats may have a dedicated windlass battery close to the bow.
Alignment with the bow roller is critical for both the vertical and horizontal windlasses. The manufacturers should provide details.