Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1   Report Post  
root
 
Posts: n/a
Default bilge keeler - tidal wear & tear?

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

  #2   Report Post  
Terry Spragg
 
Posts: n/a
Default

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

  #3   Report Post  
ChrisR
 
Posts: n/a
Default


"Terry Spragg" wrote in message
...
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


I had a Westerly 30 Bk on a thames estuary mud berth near tilbury for many
years where there was a strong tidal flow reasonably rough water in gales
and very heavy wash from large ships in close proximity. The boats on
swinging mud berths rotate about the mooring root twice a day and point
direction is influenced by tidal flow, wind and river current. After a boat
has been on its mooring for a while the boats sit in a circle of very soft
mud surrounded by harder mud that hasn't been affected by the boat. In
severe or unusual conditions the boats are thrown against their moorings and
outside the usual circle of soft mud. The rudder is then very vulnerable and
I have lost one before in these conditions removable or lifting rudders can
help. The replacement for the grp spade rudder I fabricated out of stainless
steel rather like a model aeroplane wing and it lasted fine.


  #4   Report Post  
Michael
 
Posts: n/a
Default

The main danger is keel spread. Most prevalent in older boats such as the
60's Westerly's and when the boat is on the dry for extended periods. What
you have to do is put cleats on the outside of the keels. Not realizing
this my heretofor always dry Centaur developed leak problems where the keel
joined the keel stub but only after being on the dry for three months. The
inside of the early keel stubs was a long hollow trough like area. In later
models transverse stiffeners were built in which served to stop this
problem. On the dry you still want the outside cleats as it's supporting
it's entire weight 24/7. In the tidal situation the problem is far reduced.
In tidal water you want to pick a spot where the bottom, if possible, is
fairly even and does not have large rocks littering the area underneath,
rememberingthe anchor is the center of a circle while the diameter of same
is described by the stern. In my current boat a Westerly Berwick we've
applied all the lessons learned and so far no problem.

M.

"ChrisR" wrote in message
...

"Terry Spragg" wrote in message
...
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


I had a Westerly 30 Bk on a thames estuary mud berth near tilbury for many
years where there was a strong tidal flow reasonably rough water in gales
and very heavy wash from large ships in close proximity. The boats on
swinging mud berths rotate about the mooring root twice a day and point
direction is influenced by tidal flow, wind and river current. After a
boat has been on its mooring for a while the boats sit in a circle of very
soft mud surrounded by harder mud that hasn't been affected by the boat.
In severe or unusual conditions the boats are thrown against their
moorings and outside the usual circle of soft mud. The rudder is then very
vulnerable and I have lost one before in these conditions removable or
lifting rudders can help. The replacement for the grp spade rudder I
fabricated out of stainless steel rather like a model aeroplane wing and
it lasted fine.



  #5   Report Post  
Graham Frankland
 
Posts: n/a
Default

"root" wrote in message
news
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.

We had problems with 2 bilge keelers (Westerly Centaur & Berwick) on a
drying swing mooring, . In both cases, the keel stubs were damaged and had
to be reinforced. The estuary mooring we had at that time dried so far on
springs that by the time the boat floated, the tide was up to 2 or 3 kts and
the boat was dragged sideways over ridges on the sand bottom when swinging.
I doubt that any keels/hulls are designed for such repeated shock loads and
it's not unknown for keels to break off completely.

Graham.




  #6   Report Post  
prodigal1
 
Posts: n/a
Default

root wrote:
My


snip
cheers
bruce


you're using pan so you must have a clue, but you're not really logging
in and posting as root are you?

  #7   Report Post  
Jelle
 
Posts: n/a
Default

prodigal1 wrote:

root wrote:
My


snip
cheers
bruce


you're using pan so you must have a clue, but you're not really logging
in and posting as root are you?

Nah, he's Aussie, root has a different meaning there. Probably just happy to
root his wife/gf/sheep

--
With Kind regards,

Jelle Boomstra
Reply
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is Off
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Water in the bilge. The saga continues... Bob D. General 10 August 11th 04 05:42 AM
Water in the bilge. The saga continues... Bob D. Cruising 9 August 11th 04 05:42 AM
HELP! Water in bilge when running... Bob D. General 13 July 16th 04 01:32 PM
HELP! Water in bilge when running... Bob D. Cruising 13 July 16th 04 01:32 PM
bilge colour Jürgen Spelter Boat Building 2 May 17th 04 07:49 PM


All times are GMT +1. The time now is 03:09 AM.

Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 BoatBanter.com.
The comments are property of their posters.
 

About Us

"It's about Boats"

 

Copyright © 2017