Lewmar
Hardware
Choosing the right deck hardware makes for a
smooth running boat with optimal performance. Sheets and
halyards must run freely, be accessible for each crew
function and handle the loads for which they are
intended.
Correct positioning on the deck, correct sheave
size for a particular application, and having the right
system all contributes to ease of handling and efficiency
of the combined human and mechanical effort.
Sail area, different rigs, heavy or light
displacement, multihull or monohull, are all factors
which affect yacht deck hardware specifications. Where
there is doubt, loadings should be obtained from the
designer and matched to the safe working load of the
hardware. The Lewmar hardware Block Selection Guide gives
the appropriate size of block for a given application
against boat length.
Sailors are benefiting from advanced technology
in materials and construction used in the very latest
blocks, whether for footblocks, mainsheet or kicker, or a
multitude of other configurations. Blocks such as
Lewmar’s Synchro Block are extremely lightweight with
unprecedented load bearing capacity, and use a free spin
self lubricating bearing. Meanwhile super-lightweight
racing blocks are available either with roller bearings
for rapid sheet trim or with plain bearings for high
static loads. Most Lewmar block ranges feature single,
double and triple blocks with becket, camcleat and fiddle
options as well as various deck mounted configurations
such as stand up, cheek blocks, footblocks and jammer
blocks.
Lewmar hardware guides the user through choosing
track and cars – most commonly used for the mainsheet and
for adjusting genoa sheet leads. Clutch selection is also
explained – clutch technology and rope grip systems have
evolved significantly to not only support greater loads
but to achieve release under load, and low rope
wear.
WINDLASSES
Windlasses are situated at the bow of a boat and
used for retrieving chain and anchors. They can be used
on both power and sail boats. There are different styles
of windlass and with a small amount of maintenance
annually they will give years of untroubled
anchoring.
In order to select the proper windlass for your
boat, three questions should be answered:
1. How long is my boat?
Most reputable manufacturers will have
recommended sizes of windlass for each size of
boat.
2. How long is the anchor rode you wish to use
and will it fit into your locker?
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. The measurement is
important in determining whether your boat will be best
suited for a vertical or horizontal windlass.
Horizontal windlasses
The Horizontal windlass is a no-nonsense design
widely used by boaters requiring optimum performance from
their anchoring system. Boaters who frequently anchor,
especially in deep water, require a no-hassle
self-tailing system. The horizontal windlass offers the
best performance with smaller or unusual locker designs.
As the anchor rode enters the gypsy it makes a 90° turn
and feeds directly into the anchor locker. A minimum fall
of 30cm (12in) is recommended.
Vertical Windlasses
Vertical windlasses provide aesthetic value and
offer the added security of the anchor rode making a 180°
wrap around the gypsy. The inherent design of the
vertical windlass requires at least 30cm (12 in) of
fall.This is to allow gravity to properly self-tail the
anchor rode through a 90° vertical turn into the anchor
locker. Additionally, nylon line is lightweight and a
short fall in a vertical windlass system might prevent
the rode from feeding completely in to the
locker.
3. How much pulling power should my windlass
have?
Having selected the vertical or horizontal
windlass sized for your boat length and displacement, the
correct windlass pulling power for your needs must be
determined using the following formula:
First determine the total weight of the ground
tackle which comprises the anchor and rode.
For example:
The weight of your anchor = 10kg
(22lb)
The weight of your anchor rode = 4.58m (15ft) of
chain (4.58 x 1.09kg/m or 15 x 0.74lbs/ft) = 5kg
(11lbs)
61m (200ft) of rope (61 x 0.09kg/m or 200 x
0.06lbs/ft) = 5.5kg (12lbs)
Total weight of your ground tackle = 20.5kg (45
lbs)
Second, take the total weight of the ground
tackle and multiply it by a factor of three to arrive at
the required windlass pulling strength. The factor of
three covers the effects of windage and the speed of
tidal current and includes a safety margin for unknown
circumstances.
In our example, the required windlass pulling
strength is 61.5kg (135 lbs), 3 x 20.5kg (45 lbs). Safety
guidelines suggest that the required windlass pulling
strength must not exceed one-third of the maximum pull
capacity on the windlass. Therefore, our selection of
270kg (600lbs) pull windlass is correct as the 61.5kg
(135 lbs) required pulling strength is well below
one-third of the maximum windlass pull
capacity.
Working Load
In a typical anchor recovery situation, the
windlass will pass through a number of phases of
operation as the boat approaches the anchor and finally
breaks it out of the seabed. The load and speed will vary
at each phase. For any anchor recovery, the windlass will
operate longest in the ‘working load’ phase and it will
experience a significant peak in load during anchor
breakout.
Electrical Circuit
Protection
Any installation of electric powered windlasses
must be protected with a circuit breaker. This ensures
complete protection of the electric motor and
installation cables if the windlass is overloaded.
Circuit breakers are normally rated on a ‘continuous’
basis. This is the load in Amps, under which they will
retain electrical contact for an indefinite
period.
For example, a 70A circuit breaker will not trip
unless the continuous current loads exceeds this figure.
However, the maximum tolerated current draw may be as
much as 250A, but only for a short period of time. All of
our windlasses carry a recommendation on circuit breaker
rating based on continuous operation. Remember that
motoring up to the anchor while using the windlass to
retrieve the anchor rode and using the boat to "break out
the anchor" is the proper anchor recovery procedure.
Using the windlass to haul the boat to the anchor is not
recommended and will result in damage to the windlass and
motor.
Safety At Anchor
Windlasses are not designed to hold high loads
while a boat is at anchor. When the windlass is not in
use and the boat is at anchor, the anchor rode should be
secured using a chain stopper or attached to a load
bearing point such as a cleat.
WINCHES
The size, type and position of a boat’s winches
are usually specified at the design stage and will
thereafter function well for decades, with a regular
service and few spare parts. But for an owner choosing
new winches or improving the deck functions on a boat, it
is important to ensure that the right winch is installed
on the correct area of the boat to perform a particular
function.
From the very smallest single speed winch, which
might be mast-mounted on a day boat for main halyard use,
to the large high-technology carbon winches used on
America’s Cup contenders, there
is a plethora of sizes in between. Typical standard and
self tailing winches are one, two-speed or three-speed
and manufactured of alloy, chrome or bronze.
For larger loads or short handed sailing winches
can be adapted to push button electric operation by
installing a power drive unit, either at the time of
installation or at a later stage. Operation can be
cleverly controlled with the option of a variable speed
controller too, via a simple push button console of
pre-set or variable speeds for easy sail control.
Hydraulically powered winches are also
available.
Winches are also available in stainless steel
for a prestige finish or alloy for lightweight yet top
racing performance. The rope grip on the drums developed
by leading winch manufacturers is designed to balance
optimum grip with minimum rope wear.
Race boats often have their winch systems
connected to one or more pedestal grinder. These are
connected via a series of shafts and clutches to allow
several persons to wind one winch at a time, thus
increasing speed on tacks.
Increasingly popular for superyachts and large
cruising boats is the Captive Reel Winch, also known as
the Line Management System (LMS). The LMS neatly stows
spare sheet out of sight below decks as winches are wound
in, keeping deck layout clean and uncluttered
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