Net Dynamic Menu by Vista-Buttons.com v4.3.0
We are listed on and
|
Anchor windlassBy Captain Scott FratcherThis article discusses anchor windlasses, anchor deployment systems and trouble shooting.An anchor windlass is used for more than just raising the anchor. With a little forethought the windlass can also be used to kedge off, deploy a second anchor, raise a sail, serve as an emergency tow point, or provide assistance in high wind and current berthing situations. In the basic form a windlass is used to haul up the anchor. The anchor
raising system carries heavy loads and can be dangerous. Ideally the
system should be “no touch”. In other words the operator
should simply push the button or crank the handle to deploy or raise
the ground tackle. Windlass styleWindlasses come in horizontal or vertical configuration. While they can each deploy an anchor they have specific other benefits as well. For example a vertical windlasses can pull line from any direction parallel with the deck. This makes for easy kedging. Horizontal windlasses can pull fore and aft in line with the mast. This makes for easy hauling of crew up the rig. Lets look at some other advantages of different windlass styles.
Vertical WindlassesA vertical windlass tends to have 180 degrees of chain wrap providing
a more secure chain “grab” of 3 to 5 links. Vertical windlasses
tend to take up less deck space, but must be matched to deck thickness.
The motor and gearbox are fitted below decks where space must be provided
in a “wet locker” space. The motor can be serviced without
removal of the windlass, but the motor lives in the damp area. Vertical
windlasses specifically are not recommended to use as a boat’s
securing point. In other words if your vessel is under tow it is not
recommended to loop the tow line over the gypsy. Horizontal WindlassesA horizontal windlass tends to have 90 degrees chain wrap, seating 2 or 3 links, which can “skip”. This may mean slipping chain in foul sea conditions. Horizontal windlasses have the distinct advantage of mounting without concern of deck thickness, or below deck obstructions. A wide, thick king plank is not an issue when only simple thru bolts mounts the windlass to the deck. Horizontal windlasses can also service more than one anchor. It’s simply a matter of ordering an extra gypsy to fit on the other side of the windlass. Some models provide an added line gypsy to provide up to four line handling options. Lastly, and possibly the most important benefit of a horizontal windlass is the housing is directly bolted to the deck, thus the winch may provide “horns” that can be used as a mooring or towing post.
Chain LockersThe chain locker should be narrow, deep, on the centerline and for
weight consideration as far aft as possible. The chain locker should
be able to handle a minimum of 75 to 100 meters of chain. Chain locker
drainage should be thought out, running either overboard or routed into
the bilge.
Secondary UsesA decision to make when purchasing a windlass is what secondary uses the windlass may encounter. A capstan on a vertical windlass can make for easy kedging, but needs a second block to help haul someone up the mast. It’s worth planning out simple methods of running lines on the bow so kedging, docking, or towing is thought out ahead of time. In this way, during docking a bow line can be passed and secured to the dock. The bow crew simply pushed a button to reel in the bow line to proper tension providing a safe method of controlling even the largest vessels. For this reason a windlass with a separate line gypsy and chain point are an advantage. Simply loosen the break and wrap the line over the remaining gypsy. Remember to plan for port and starboard line feeds.
InstallationInstallation considerations are more complex than simply following the installation instructions. The location choice must considered carefully. The placement must be one that allows the anchor to secure to deck without rattling. The chain must fall through gravity into the chain locker without help from the operator. If space permits it’s often a good idea to mount the windlass so the vessel can take an anchor one size up from the current anchor to accommodate cruising or storm anchoring. The up/down buttons should be located in an area safe from accidental activation, but in a location the operator can see the complete run of chain during operation. This is particularly important during the final seating of the anchor. When the anchor shank reaches the roller the anchor will often be swinging and twisting. Tapping the ‘up’ button at the exact right moment will ‘snap’ the anchor home into the roller. The area chosen to mount the windlass must be extremely strong. The anchor windlass can produce tremendous loads on the foredeck. The bolts should attempt to ‘grab’ the foredeck in such a way no flex is possible. Flex over time will cause leaks that start the downward spiral of maintenance and replacement. Large backing plates that cover an area much greater than the actual windlass will help reduce flex and increase ultimate strength. The windlass needs to be mounted down with some type of sealant. Some recommend using a strong bonding sealant such as 3M 5200 claiming the extra attachment to deck provides more strength in the mounting. Others argue using a bonding sealant that is too strong will discourage the dis-mounting” for service causing more problems in the long run.
The Chainwheel to chain connectionThe gypsy connects the windlass to the chain or line. The critical issue is chain wrap. Wrap translates to contact area. The better the connection between the chain and the windlass the less we have to concern ourselves with the chain skipping or jumping. Nothing increases chain contact are like increased diameter. If space is a problem some chain wheels arrive with a spring loaded chain capture device that can help overcome some skipping issues. Besides chain wrap it is critical the chain size matches the chain wheel perfectly.
Chain SizeChain size is more complicated than simply knowing the typical “8mm
or 10mm chain”. To match the chain to the gypsy the following
should be measured and kept as a record onboard. If you are unsure of your chain size you can send an 11 link sample to Maxwell Marine in Albany and they can do a proper sizing in their complete factory. They have an amazing chain library and will likely be able to identify yours.
Chain typeAnchor chain type is more complicated than just diameter, and dimension.
We also have manufacture grades. In New Zealand we have four basic grades
of chain. What this size/grade of chains means to the boatie is careful measurements and records must be kept, so the ordering of new chain is easy and trouble free.
Chain twistWhatever chain you decide on be sure to use a swivel between the anchor and the chain. This swivel will help prevent chain twist that can cause skipping of the chain on the gypsy thus preventing premature wear and possible damage.
Bow rollerThe bow roller is meant to secure the anchor while in port and provide a smooth method of passing the chain into the water The farther the bow roller extends from the boat’s bow the less chance of the anchor swinging into the hull causing paint chips. However a long bow roller means greater strength and support structure is needed. It is recommended a groove be built into the anchor roller. This groove helps keep the anchor chain in a steady line during the raising or lowering of the chain and further preventing twist or chain skipping.
MaintenanceA windlass is often the most neglected piece of equipment on board. It’s located in the worst of the sea spray exposure and often gets little more than a casual pre-season cleaning. A windlass is a fairly simple mechanical device and worth spending a bit of time to get to know. Richard Arthur of Maxwell Marine recommends using CRC type spray on the electronics every season along with pulling the gearbox apart every three years to inspect the seals and change the oil. The clutch cones must be greased, even though they arrive dry. The electric motor should be opened and the carbon from the motor brushes removed.
ChainstopperThe windlass is not meant to hold the load of the boat while at anchor. This is the job of the snubber, or the chain stopper. Cyclical loads due to passing waves is the number one reason windlasses wear. “The windlass is a winch for hauling and deploying chain, not a mooring post” says Ron Czerniak, Marketing Sales Manager at Maxwell. A snubber is a simple line with a hook or rolling hitch that grabs the chain holding the boat’s load. This line adds a bit of “spring” to the anchor system and prevents the multiple loads from wearing the windlass drive. A chain stopper is mounted to deck between the windlass and the roller. This securing point holds the chain load. An added benefit of the snubber or chain stopper is the windlass is free for other uses, like controlling a second anchor or lifting our crab pot for dinner.
Winch powerThere are three common methods of powering a winch.
ElectricElectric is the most common form of power on the smaller yacht. The windlass motor is simply a small starter motor that is connected to a gearbox. The yacht will need a good strong electrical system to support an electric windlass load. A windlass can draw 60 amps reeling in chain without a load, and over 300 amps when working hard. Electric has the advantage of an easy, clean installation. The most common problem when installing an electric windlass is undersized feed cables. Remember long runs at 12 volts equals voltage drop. Voltage drop means increased amps and heat in the windlass, shortening the life of the windings. Note-When running large low voltage leads it is critical the leads do not cross each other. The crossing point can make a chafe spot that can become a fire hazard. Instead run the cables next to each other paying particular attention to the feed at the winch.
HydraulicHydraulic power is common in boats above about 18 meters. A large windlass, and long run times are common reasons to use hydraulic power. Hydraulics make particular sense if the boat already has a hydraulic system installed. IE deck winches, fishing winches etc. Hydraulics have two distinct advantages over electrical. Hydraulics have a reputation of running trouble free in extremely wet conditions and they don’t need a reduction gear. The reduction gear from the high RPM electric motor to the winch is a source of wear and expense of a windlass system. Hydraulic motors run at low RPM’s and high torque thus eliminating the gearbox.
ManualManual is the preferred system for boats with little or no electrical supply or for those on a tight budget. The main advantage is dependability. Manual windlasses rarely fail, or run out of power. They tend to be slow and in cases of emergency or short handed sailing can make for difficult choices between time at the helm and time on the foredeck. Better manual winches have two speeds giving greater options.
Trouble shooting an anchor windlassAnchor windlass problems typically fall into three categories Slow response in an electric windlass normally means: Start the trouble shooting by testing voltage at the motor while under load. The voltage should be above 12 volts. Less means voltage drop in the feed cables, or a poor connections. Work your way back along the cables toward the batteries or power source testing at each connection till you find the voltage drop. Slow response with good voltage may mean internal windings may have begun to fail, or the motor may be binding internally. IE rusted bearings or swelled rotor. Slow response may also mean the electric motor has begun to work it’s way loose from the gearbox. Switch the windlass from forward to reverse and watch the motor. You should not see any movement. If you see the motor wiggle this is a sure sign the housing has come adrift and needs some the bolts tightened. Slow response in a hydraulic windlass may mean a worn motor vanes or low supply pressure. Check pressure at the motor (as you would voltage) and follow the same procedure you would in an electrical system working your way back till you find good pressure.
No responseNo response typically means a complete loss of power IE fuse, a solenoid had failed, or the small control circuit wires have come adrift. Check for control voltage at the solenoid control lugs. A good reading of control voltage means the wires and supply circuit are working, but the solenoid is not passing the voltage or hydraulic pressure. Skipping and clogging chain Partitioning the chain box with timber, to make the chain area taller, can sometimes rectify this clog. Sometimes a crew member has to stay forward flaking the chain with a boat hook to prevent the pile up. Clogging on deployment is often caused by chain that has fallen onto itself, or is paying out so fast the chain does not have time to hang straight. Slowing deploying chain till the first third is released can help. Skipping chain is caused by miss-matched chain to the gypsy or the chain my have worn or stretched, or the gypsy may be wearing out. Stretched chain needs replacement, while a worn gypsy chain pockets can be built up by most any engineering shop.
|
Articles originally published
in
Horizontal windlass
|
|
||||
© Team Yachtwork 2009 |