Notes from the
IABBS
(excerpts from the magazine)
by Richard "Jud" Henderson
More Tips For The Amateur
Builder
While aimed primarily at the sailboat and the
designer, this is sound advice for those who design and build their own
boats or consider modifications. And much of the advice also applies to
power boats.
It was suggested that this article for IABBS
concentrate on features related to safety and seamanship. The following 10
suggestions are among those I think are most important and surprisingly
they are often overlooked or inadequate on many sailboats whether they are
built by amateurs or professionals.
1. Cockpit safety -
If the boat does not have a bridge deck, the companionway sill should be
well raised. Otherwise, there should be a heavy drop board that can be
inserted and locked into the bottom of the companionway opening whenever
there is a threat of heavy weather. Even if the boat is sailed in
sheltered waters she could be knocked down by a heavy squall. I remember
hearing of a boat with a low sill sinking in one of the Chesapeake Bay's
most protected harbors after she was knocked down by a sudden squall
before the sails could be lowered. She lay on her side and water rushed
below over the low sill quickly filling and sinking her.
2. Water tightness -
Another safeguard against down flooding is to locate all hatches on the
boat's centerline. White squalls or downbursts, as they are now called,
are not uncommon in clear weather when hatches are open. One offshore
sailor of my acquaintance experienced three severe knockdowns from white
squalls and he became a strong advocate of on-center hatches. Be sure
there are proper hatch dogs and that all vents can be covered.
3. Accessibility -
On many stock boats liners or ceilings obstruct accessibility to the
interior of the hull and overhead where chain plates, bolts, nuts, etc.
need periodic inspection and possible servicing. Of course there should be
good access to the engine, Filters, tanks, stuffing boxes, batteries,
valves and the steering quadrant, but this is often not the case.
4. Heeling
considerations - Seldom are there adequate fiddles on shelves or
rails on the cabin table to keep books and other items from falling (or
flying) when the boat heels. Even powerboats and multihulls can roll to
considerable angles. As for friction latches on locker doors, don't
consider them unless you intend boating on a Disney World pond!
5. Motion considerations
- Unless you are on that Disney pond, our boat will be thrown
around by waves. Even on protected waters on calm days there will be
powerboat waves. To prevent falls and alleviate injuries from being thrown
off balance there should be ample bolted-on grab rails above and below
deck. There should be no sharp corners on a boat, and objects such as
bolts, beams, or knees with which a person could make contact should be
padded. Needless to say, all slippery surfaces must be skid-proofed.
6. Bilge - Many
modern boats with canoe bodies and bolted-on fin keels lack a sump for
bilge water. This means that any water in the bilge, which is often oily
or otherwise unattractive, will roll up under the bunks and into lockers
when the boat heels or rolls. Bolted-on fins are best when secured to a
keel stub which can house a sump. Be sure that all keel bolt nuts are
accessible. Limber holes and drains for keel-stepped masts are seldom
adequate. Inside ballast must be securely wedged or fastened in the bilge.
7. Mast step -
All too often, when the mast is deck stepped, there is inadequate support
under the mast. Apparently many builders or designers don't fully
appreciate the enormous downward thrust of a mast when the rigging is set
up and the boat is close hauled in a fresh breeze. I favor a metal pipe
under the mast. resting on substantial floors when this is possible.
Otherwise a metal beam straddling heavy vertical posts.
8. Plumbing -
Another aspect of water tightness, a very important one, has to do with
plumbing. All hoses penetrating the hull should be fitted with valves,
preferably seacocks (rather than gate valves). Fixed bilge pumps often
need high loops with siphon breakers to prevent back siphoning when the
boat heels. The top of a flow-through head should be above the waterline
because valves can fail. Sinks are best located near the boat's centerline
to prevent flooding when heeled, and unless the engine exhaust line has a
high loop there should be a cutoff valve at the exhaust outlet.
9. Electrical -
Careless electrical installations can result in not only loss of power,
but also fires and serious corrosion. The safest policy is to follow the
standards set forth by the American Boat and Yacht Council. Underwater
metals need sacrificial zincs (or magnesiums) to protect against galvanic
corrosion, and whenever possible compatible metals (those close together
on the galvanic scale) should be used. When not possible, a durable
barrier must be used to isolate the incompatible metals. Many boats are
not grounded for lightning protection, but it is certainly advisable in
areas where there are frequent thunderstorms.
10, Rig - A book
could be (and has been) written on the subject of safe and seamanlike
rigs, but what follows are a few important points. Probably more serious
accidents aboard a sailboat result from crew being "beaned" by the main
boom. Make sure the boom is sufficiently high above the cockpit.
Surprisingly often, the boom is too long to clear the permanent backstay
during a goose wing jibe. Many contemporary racers forego the permanent
backstay for runners, but this risks loss of the mast if a runner is not
set up promptly and properly after changing tacks. Double lower shrouds
with ample fore and aft spread between their chain plates help prevent the
mast from pumping in a seaway and could prevent its loss, a definite
possibility when sailing under a large jib alone. All measure should be
taken to prevent chafe and metal fatigue. This means that blocks are
swiveled, that chain plates and tangs are properly aligned to prevent back
and forth bending, and that toggles are used between a stay or shroud's
terminal fitting and its chain plate or stemhead fitting. |