root wrote:
My 28ft bilge keeler bounces around a good deal when the tide has moved to
be settling or lifting the boat.
Not only does it get damn noisy but it can get a bit frightening when wind
& wave combine to cause it to pitch up on one keel. But thats not my main
worry, I'm more curious to learn from folk who permanently moor in the
shallows and effectively have their boat on the dry once or twice a day.
Does this long term bouncing about cause any strutural damage? I'm
thinking it cant be doing my radar dome any good either.
I've just done an ad-hoc solo 2200mile voyage from southern New
Zealand to north Queensland. Conditions went as bad as 55knot gales with
7m seas the boat handled it a damn site better than I did.
cheers
bruce
Drying moorings with bilge keelers are best located over soft
bottoms. The sand, whatever, squishes during transition of the
tide, and all should be well. Once the keels touch down, only the
weight of the hull minus it's bouyancy plus it's mass coupling
delta-vee matters to the keel roots. Wet mud is an excellant
cushion. I wouldn't worry about your rig. You can fix your pendulum
mount. Rubber mounts?
A drying mooring with waves will, likely at least 50% of the time,
end up with the boat head to waves. Once unstuck, the boat rises
perceptibly above the grooves in the mud, after rocking a bit from
the grounded flat keel to front afloat / back afloat, bonk a pointy
rudder, etc. Likely only a few inches.
The noise is amplified by the absence of distractions and fear. Even
a far off power boat will sound loud through the hull, remember?
Over a lumpy bottom, structural damage might well occur. Even the
mooring weight counts as a lump. Good reason for a chain mooring and
a long painter with a kellet mid span to a stern anchor? Yuchy mud
on everything. Got an engine driven wash pump?
"...use it." - Un-named Commissar in "Dr. Chivago"
On ROUGH days, we all took our chances. Most still float.
Terry K
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