| Our
web site has been up for over four years now, and as time passes,
some of the information gets dated. So, it's time to update
one of our most popular pieces, The Top Twenty five Design
Errors.
I've changed the name to Top Twenty
because I'm no longer including the sailboat information as
we have limited ourselves to powerboat surveys only. So,
here we go.
1. Badly made
deck-to-hull joints. Leading the pack of serious faults
is badly made deck-to-hull joints. So much so that I have a
dedicated article dealing with this rather complex subject.
When buying a new or used boat, it pays to research this issue
carefully. Read the article and you'll find out why. Hull to Deck Joint (at www.docksidereports.com
)
2. Sealed off hull compartments.
Meaning that the new trend in boat building is to eliminate
all access to areas of the internal hull. This often results
in compartments between stringers and bulkheads that are sealed
off by the cabin sole. If water leaks into these compartments,
this can result in filling up with water and cause deterioration
of structural hull members such as stringers and bulkheads.
Why Internal
Hull Areas Should Be Accessible
3. No structural bulkheads
still leads the list of major engineering faults of small cruisers
that aspire to provide a cavernous interior, uncluttered by
nuisances such as things like bulkheads and other structural
hull members. We continue to find many small boat interiors
breaking apart due to tort ional hull twisting. And poorly supported
fore decks that, when you jump on them, the port holes or windows
pop out, due to a complete lack of framing or support that bulkheads
would otherwise provide. What appear to be bulkheads are usually
just partitions, space dividers that are not attached to the
hull. Hull Design Defects
Part I | Hull Design Defects II |
4. Low quality plywood
used for hull structural members. Some of the plywood material
we see used in many of the most popular entry-level boats is
the lowest quality plywood available. Absolutely the bottom-of-the-barrel
stuff. It's rough with exposed knots and lots of voids in the
plies, all of which allows water to get into the wood with the
inevitable results. Preventing
Rot in Encaplulated Wood Structures
5. Plywood structurals
such as stringers and frames painted with gel coat. Many
builders are trying to make it look like their stringers and
such are glassed over when, in fact, all they have done is to
paint a heavy layer of gel coat on them. Since you already know
that gel coat is very good at absorbing water, the plywood also
absorbs water, swells up and causes big cracks in the gel coat.
Then the plywood absorbs even more water. Preventing Rot in Encaplulated Wood Structures
6. Improper aluminum
fuel tank installation. You'd think by now, after all these
years of terrible fuel tank problems, builders might be a little
more careful about this. But, no, we find even the likes of
Sea Ray doing a bad job of it. There is no excuse for mounting
an aluminum fuel tank on a plywood deck that will come in contact
with bilge water. How to Install an Aluminum
Fuel Tank
7. Interior cabin soles
build just a few inches above the bottom of the hull. You'll
find this on nearly every small, so-called "aft cabin"
cruiser. With no space beneath the deck to mount a bilge pump,
and the only pump located in the stern, the end result here
couldn't be more predictable.
8. Badly designed engine
hatch gutters, or no gutters at all. A few builders have
gotten better at making engine hatches capable of keeping water
off the engines. Others haven't. An engine hatch must absolutely
be capable of keeping water off the engine, otherwise, you pay
a high price for corrosion damage and the potential for engine
failures.
9. No gutters on rope
locker hatches. We see numerous cases where an anchor windlass
is installed with the drive motor being located in the rope
locker that has no gutter. This lets salt water cascade directly
onto windlass motors and associated electrical components, bringing
on an early and costly demise to these expensive components.
10. Non insulated air
conditioning ducts. Sweating ducts drip condensation onto
plywood components causing water damage. A/C ducts must be insulated.
11. Improper mounting
of steel chassis electrical devices such as water heaters,
battery chargers and power trim motors. Usually mounted on a
flat deck that collects and retains water, these items then
quickly rust out because they are constantly sitting in water.
This is often aided by water heaters that have no drain hoses
attached to the pressure relief valves which drain water onto
the base that the heater is sitting on. Battery chargers mounted
near hatch openings so that these get wet.
12. Leaky cockpit decks.
Particularly in the mid to large size express cruiser class.
Components like seating modules are mounted in cockpit decks
by putting bolts through cored decks. Or holes are thoughtlessly
drilled through the decks that allow water in. In one case,
the large hatch gutters angled forward while the drains were
located aft. Wet the deck and gallons of water would pour into
the engine room of a $300,000 boat. Deck
Leaks
13. Improper design or
installation of center consoles. Numerous instances
of consoles screwed down to cored decks. Consoles break loose
or water gets into deck core.
14. Improperly designed generator
exhaust systems, particularly in sport fishermen. Transom
outlet allows water to be pushed back through exhaust and into
engine.
15. Chine walking and loss
of steering control. At high speed, boat lays over on its
side. Trim tab inputs result in extreme and unwieldy responses.
The causes of this are complex, but well known. The main reason
this occurs is that the designer didn't know what he was doing,
and the builder didn't bother to test the performance, or bother
to correct the problem. He gets away with this by ascribing
the problem to "operator error." Large numbers of
boats are affected with this problem.
16. Poor low speed handling.
Usually caused by propeller pockets and very small rudders,
there is nothing to steer the boat. The current trend in placing
engines and propellers very close together-- in many cases engines
almost touching each other -- results in poor handling at any
speed, and also contributes to chine walking. The reason for
this is to achieve greater interior space, sacrificing interior
amenities for performance, hence the term "floating condo."
17. Weak, unsupported
hull sides. In the never-ending quest to increase profit
margins, the concept that hull sides should have framing or
some means of support to prevent panting or panel deflection
has been thrown out. Panting or buckling hull sides contributes
to problems at the deck/hull joint, particularly if it is only
screwed together. Hull side panting also results in stress cracking,
leaking port holes and frequently severe problems with interior
attachments, such as cabinets and galley modules going adrift.
Are They Fiberglass Boats Anymore?
18. Sensitive electrical devices
installed in exposed locations. The include panels, switches
and main shore power circuit breakers. Unskilled designers
are taking increasing liberties with installing electrical apparatus
in locations that get wet and result in water damage and system
failures. You pay the cost for this ignorance.
Electronics
Outside
19. Poor gel coat finishes.
Despite the claims of manufacturers, gel coat finishes have
gotten no better, and in some cases worse. Example: a one year
old 40' Formula where the finish luster was completely gone.
It's time to give up on gel coat and start painting boats with
linear urethane like Hatteras does.
20. Large cockpit seating
modules on top of large electrically opened cockpit deck hatches.
This is turning into an unmitigated disaster. Engine compartments
that only open two feet, making engine room access and servicing
extremely difficult and physically painful. Tiara is one of
the worst offenders. This kind of design should stop as it is
seriously driving up the cost of servicing and ownership.
Hint to designers. Here's a great
place to put those ultra light, high tech composites to work.
Make the seating modules ultra light. Then put nylon runners
on the bottoms so that they can be slid (not carried) off the
hatches, without scratching the deck, so that the hatches can
be fully opened. Do us a favor and put the pleasure back in
boating.
Related Article: Recent Design,
Construction and Materials Improvements - 1996-2000 Models
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