PART II .....how to install the rigging

.....installing fittings to the
hull
GENERAL PRINCIPLES
Fittings for the running and
standing rigging must be capable of resisting considerable strains.
Therefore, it is always recommended that fittings be through bolted
whenever possible, with the fitting being backed up with oversized solid
blocking, especially on the underside of thin fiberglass or plywood
surfaces such as decks. Use large flat washers under nuts, and bedding
compound under the fittings to prevent leaks. Where it is not possible to
use through bolts, then long screws of the largest possible shank diameter
should be used, driven into solid material below. These rules apply to
fittings wherever they may be required, whether on cabin tops, cockpit
soles, decks, or centerboard trunks.
On wood hulls, finding solid
material or providing solid backing blocks is usually a simple matter. On
fiberglass hulls, backing blocks may have already been fitted when the
hull was fabricated, or the hull may have been reinforced with extra
laminate build-up in the area where fittings are to be located. If this
hasn't been done in one form or the other, the builder must provide the
solid backing material to receive the fastenings for the fitting. The wood
blocks can be secured in place with a resin saturated piece of fiberglass
cloth or mat.
Fastenings in all cases are
preferably a non-corrosive type, which usually means stainless steel,
bronze, or at least hot dipped galvanized. Do NOT, however, use hot dipped
galvanized fastenings with, for instance, bronze fittings, as the two
metals are dissimilar and corrosion will dissipate the fastener (at least
in salt water). A good rule-of-thumb is to use the same type material in
the fastenings as is used in the fitting, except that stainless steel can
be used to fasten into aluminum.
INSTALLING CHAINPLATES
Chainplates may be located on the
outside of the hull, usually along the gunwale or hull side rail. For a
neater appearance, however, it is more common to have them located inside
the hull, projecting through the deck or cabin top. When they are located
inside, this usually means that they must be mounted in position prior to
the completion of the hull, and especially before the decking is applied
(see Fig. 7-1). The position of the chainplates should be determined by
the designer or manufacturer of the boat. This position will usually be in
conjunction with a main strength member such as the hull sides, structural
bulkhead, or other longitudinal framing member. As with other fittings,
solid backing blocks, or extra reinforcing of the hull on fiberglass
boats, should be provided for mounting the chainplates.
FIG. 7-1 - If building a boat and
through-deck chainplates are called for, they should be installed
and bolted in place before the deck is applied. The photo shows the
chainplates bolted in position on each side, protruding far enough
above the deck line to receive the turnbuckle or other stay
hardware. (Glen-L 10 is shown) |
Chainplates can be made of any
strong metal as long as it is non-corrosive. However, it is common to
purchase ready made chainplates which are usually made from stainless
steel strap with holes usually drilled in each end. If in doubt about
which size chainplate to use, always pick one that is larger and as long
as practicable. Always bolt the chainplate in position with at least two
bolts per unit. Be sure to let the top end of the chainplate extend far
enough above the deck or cabin top to allow the shrouds to be attached.
Where chainplates protrude through the deck or cabin top, the hole should
be sealed in a water proof mastic. Special covers are available which
match the ready-made chainplates to cover the hole and "dress up" the area
where the chainplates pass through.
If in doubt about the location of
the chainplates, remember that they are located as far outboard as
possible, as far as strengthening the mast is concerned. They must not,
however, interfere with sail handling; especially when a jib is used.
Also, if a single shroud on each side is used, the chainplates are usually
located a little aft of the mast. When upper and lower shrouds are used,
the chainplate for the upper shroud is usually directly to the side of the
mast. The chainplates for the lower shrouds are then located a slight
distance forward or aft of this chainplate. When more than one chainplate
is required per side, they should be separated by a distance of at least
several inches in order to transfer the strains to the hull.
INSTALLING DECK FITTINGS
Deck fittings such as blocks,
cleats, winches, tracks, and related items should be installed with bolts
or long screws as previously noted. Fastenings are usually not provided
with the deck fittings when purchased because the lengths will vary from
boat to boat.
In installing fittings such as for
the mainsheet, it is advisable to mock-up the arrangement before fastening
anything permanently in position, especially if you are not familiar with
the configuration, or are figuring out your own arrangement. Tape the
fittings in position and check to see that all fittings are in the proper
position and plane of reference for smooth operation. It would be mighty
embarrassing to find that a cam cleat, for example, was fastened in
backwards! While the designer will probably note the positions of the
various fittings, the best locations for the fittings can be determined.
Also check the position of the various jam cleats which will be used to
belay the various sheets and halyards. Obviously these jam cleats must
have a "fair lead" to the line and be in a position so the line will stay
secure. Always locate jam cleats so the pull of the line is at right
angles to the line of the fastenings; not in line with them which will
tend to pull the cleat out.
If your rig has a jib, care must be
taken in locating the jib sheet lead points; the position where the lines
controlling the trim of the jib intersects with the hull. Designers use a
formula for determining these positions and it has been noted previously
and in Fig. 5-16. The builder can also use this formula, but because
conditions of use, the sails, and boats in general vary, the best method
for determining jib sheet leads is by actually sailing the boat and
pinpointing the lead position while using the jib. Admittedly, this may
seem tedious and inconvenient, but on the smaller boats with jibs up to
about 50 square feet, it is really not too much effort.
With either method, once the
correct point is determined, a fixed or adjustable lead fitting can be
installed. On small boats, a fixed lead need consist of nothing more than
a fairlead fastened to the deck on each side for each jib sheet. On larger
boats, or where more efficiency is desired, a track can be used on either
side with a sliding fairlead. This method allows for variable trimming of
the sheet when underway, which is desirable when the conditions of sailing
change. This track for the jib would be located so the mid-length of the
track is positioned at the point found to be most efficient. The track
used for the jib is usually at least 12" long. On larger boats that use a
Genoa, a separate track is provided for this sail, each side of the boat.
The lead point for the Genoa can be found by the trial-and-error method,
but because of the size of the sail, this is difficult, to say the least.
For this reason, it is better to use the formula provided to determine the
lead point for the Genoa, and then use a longer length of track for the
fairlead slide so that variations are possible. In most cases the Genoa
track is located fairly parallel along the sheer rail as far outboard as
practical. Track stops must be provided for all jib and Genoa tracks at
the ends so the slides will not come off when underway.
When winches are required for
handling sheets and halyards, their position must be carefully determined.
Halyard winches are generally fastened to the mast, but are really not
considered necessary equipment on the size boats being considered here.
This leaves winches which are used for the jib or Genoa sheets. Here again
the position of the winches will usually be noted by the designer, but as
stated previously, this will be an approximation, and the exact position
for the winches is best determined in use once the sheet lead points are
known, or at least mocked-up.
In locating winches, several things
must be considered. First, the winch must be near at hand and convenient
to use. If it has a handle, clearance must be allowed for a full circle
swing. Winches may be located on deck, but it is common to raise them up
on blocking in order to clear cockpit coamings. If the winch is blocked
up, this blocking should be angled so the lead of the sheet from the track
is fairly horizontal to the winch. A cleat is always used to secure the
sheet after taking turns around the winch. These cleats are preferably in
a horizontal plane with the winch as well.
When installing "outboard" rudders
on the transom, gudgeons and pintles, as described in the previous
chapter, are used. Sometimes inboard rudders are used, and these are
usually detailed on the plans by the designer. With "outboard" rudders,
most commonly the pintles are bolted to the rudder. The gudgeons are then
screwed or bolted to the transom. Most boats use a set of two each, and
these should be spaced as far apart as possible to distribute the strain
on the rudder. Install a rudder stop if there appears to be any tendency
for the rudder to float up and out of the gudgeons. Any number of types of
rudder stops are available, some of which may be integral with the rudder
fittings. Another method which can be used but is not very seaman-like is
to bend the pintles with pliers so they fit tighter in the gudgeons.
Installing the mast step may not
require any fittings if the mast is to be stepped through the deck and
provisions have been made in the hull structure. However, with masts that
are to be stepped on the deck or cabin top, a means of securing the mast
is required, and this is usually by the mast step fitting such as shown by
Figs. 7-2, 7-4, and 7-5. As noted previously, several types of steps are
available. Depending on the design, reinforcing below the mast step may be
required, such as a mast stanchion or large deck beam. The reason for this
extra support is that the mast is in direct compression onto the boat and
the considerable strain must be transferred throughout as large an area of
the structure as possible. So it is important that the mast step be
located directly over these strength members and rigidly mounted. Mast
steps are preferably through bolted in any case.
Chapter
8 Contents |