Dave Gerr - Boat Mechanical Systems Handbook-How to Design, Install, and Recognize Proper Systems in Boats

(Rick Simeone) #1
you’re retrofitting, reinforce the dickens out
of everything—you won’t be sorry.

Hawsepipes
Though I’ve designed a number of boats with
hawsepipes, none have ever been built that
way. In fact, Imaginewas designed with
anchors stowed in hawsepipes, port and star-
board on the bow. So far, in every case, the
disadvantages of hawsepipes have resulted in
changing to anchor rollers when the boat was
built. Hawsepipes definitely can work and
work well, however. They are particularly
appropriate and attractive for larger vessels,
over 90 feet (27 m), where the anchors are so
heavy that hawsepipes greatly simplify
anchor handling. Even so, anchor rollers can
be fitted and function nicely on such sizable
craft.
Strictly speaking, the pipes that run
down from the deck to the hull side are the
hawsepipes, and the holes exiting the side of
the hull are the hawseholes. In any case, the
geometry here is complex and will need care-
ful thought and design. Among the considera-
tions is that the hawsepipes must be large
enough and long enough to accept the full
length of the anchor shank with distance to
spare, so the anchor and chain will snug up
against the hull properly. On deck, the
hawsepipe exit must be located where it will
provide a clean, fair lead to the windlass,
with room for a chain stopper between the
windlass and the pipe’s deck opening. The
hawseholes must be located so the anchor
lies flush against the hull and doesn’t extend
forward of the bow or sit too low to the
waterline. The anchor needs to be high
enough to be clear of the normal bow wave
during routine operation.
Structurally, the hawsepipe must be very
rugged (Figure 24-13). If it cracks or breaks
free, you will have a serious leak at the bow,
which would make for a bad day on the
water.
When the anchor is deployed, the chain
tends to chafe and cut the bow, marking it
badly and potentially even damaging the bow.
You can see this in the photo of the Danforth
anchor in a hawsepipe (Figure 24-14) where
the stock has deeply scarred the hull, the
forward fluke’s bill has chafed the small pad
added for it, and the chain has marred the

stem at the waterline. If the boat is a sailboat
with bowsprit and bobstay, the chain will
foul, chafe, and bend the bobstay even worse
than a rode set through chocks on deck or
from rollers on a bowsprit; see the bobstay
in Figure 24-15. This boat also has navy stock-
less anchors—not ideal. The anchor will be
inclined to bang and scratch against the hull
during deployment or retrieval, and the chain
can be noisy in the hawsepipe. Finally, you
cannot reach down to work on or get at the
anchor. If you want to change anchors or oth-
erwise inspect them, you need to drop the

PART SEVEN: ANCHORING SYSTEMS


Figure 24-13. Diagram of a hawsepipe
(FromThe Design and Construction of
Power Workboats,by Arthur F. Johnson)

Figure 24-14. Danforth anchor in a
hawsepipe. (This bow also has a plastic
chafe pad)
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