 It
is time to make some deposits in Mustang Sally's
karma bank. We planned
a bit of
work and putting the boat to bed for a while. A bit of work became
a lot of work as a more detailed analysis revealed unexpected
challenges.
In addition to regular maintenance and decommissioning, the three major
projects of the April 2007 haul out were:
1) Rudder shaft replacement;
2) Seagull striker and fore and aft beam replacement;
3) Sail drive overhaul.
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really unique thing about this overhaul was the enjoyable and social
nature of the Dockland Five boat yard. Kitchen facilities,
barbeques, washrooms and showers were provided for use of the many
cruising boats preparing for another season. The boat yard
expected many of the boaties to live on their boats as they carried out
the maintenance jobs and tried to make it a pleasant experience.
We had a lot of fun in Dockland Five. There were many fine pot
luck barbeques with other residents.
Rudder Shafts Replacements:
 While diving to clean the bottom I had noticed what appeared to be minor
delimitation on the top of the starboard rudder. My plan was to
remove the rudder, grind out the delaminated fiberglass. and lay in new
fiberglass.
When I pulled the rudder, heavy corrosion was evident on the shaft. The
corrosion was a result of the proximity of dissimilar metals which
causes metals in salt water to act like a battery with the weakest metal
being eaten away. As the aluminum is eaten away a deposit remains
that is bigger in size than the original material. The deposit
puts pressure on the surrounding material and that pressure was what was
caused the delamitation.
 I attempted to grind out the corrosion with hopes of re-welding
the solid aluminum shafts. The corrosion was about 1/3 of
the way through the shaft so welding would have made the shafts brittle
at the welds. A decision was made to replace the shaft.
Examination of the port rudder shaft showed similar but less severe
corrosion. I decided to replace them both.
 The process was long and messy. Most of the work was carried out
with protective clothing and breathing apparatus to keep the fine
particles from getting onto my lungs and skin. I had to grind the
shafts out of the rudders, fabricate new shafts, then rebuild the
rudders. The job is done and much karma has been added to the
boat. The first shafts lasted 18 years. The use of zincs and
non-copper paint on the rudders will likely double the life of the new
shafts.
Seagull Striker and Fore and Aft Beam Replacement:
Dissimilar metals caused by poor mounting of a bow light caused corrosion
in the seagull striker. The corrosion created two holes in the
metal. The holes allowed salt water to penetrate which
was accelerating the corrosive process.
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We could not come up with a satisfactory explanation for the heavy
corrosion on the fore and aft beam. The beam was heavily holed and
filled with salt.
A new seagull striker was fabricated and
a new beam was constructed from an piece of surplus mast.
Sail drives
Overhauled:
 The sail drives had some bare aluminum
exposed and were in need of paint. When I removed them I decided
to check the seals and bearing. One shaft was bent slightly and
the bearings and seals were replaced. The units were repainted and
re-installed.
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