Sloop Du Jour had four Dorade vents installed when I bought her, two on the foredeck
and two on the aft cabin deck.  These vents, for anyone not familiar with them, are
designed to let air in and keep water out.  They do this by means of baffles, obstructions
to the passage of water but not air.  Think of the baffles as dams that air can flow over
but water (in reasonable amounts) cannot.

Over the years I found
the forward Dorade
vents to not be all that
useful.  For ventilation
I found it more effective
to open the forward
hatch (if it wasn't raining,
of course).  And the
Dorade boxes were large
enough to be impediments
to full use of the foredeck
for sunning and relaxing.  
So, after some research,
I decided to replace them
with deckplates having
screw-in interchangeable
elements.  These would allow

  • a solid element for darkness or sun blocking
  • a transparent element to let light into the v-berth
  • no element, for ventilation.  The interior side of the opening is screened to keep
    out bugs

Upon removal of the boxes and the existing thru-deck fitting, I found that the seal
between the fitting and the hull had not remained watertight.  Water had seeped into the
cored deck and caused some rotting of the core in the area around the opening.

This is Murphy's Law of Projects, isn't it -- before you can do anything, you have to do
something else.  In this case, before the new vent can be installed, the deck has to be

Fortunately for me, this occurred during August, a very hot month in Florida.  I used a
small screwdriver and similar tools to remove as much of the crumbling, rotten wood as
possible, working from the edge of the hole.  The depth of the damage seemed to be
only an inch or so, and not in all directions.  I then used dry paper towels, rolled up like a
thin cigarette, to insert into the openings and soak up as much moisture as they could by
weeping action.  I let the wood air-dry in the hot sun during the day, covering the
opening (and the screw holes of the removed Dorade boxes) when necessary to prevent
the re-introduction of moisture from the brief afternoon showers that are so common

After the core was thoroughly dry, I covered the v-berth
underneath the openings with layers of newspapers as a
drop cloth.  I used duct tape to seal the bottoms of the
Dorade box mounting screw holes.  I mixed up a batch of
West System epoxy (105 Resin and 206 Slow Hardener)
with a small amount of 403 Microfiber filler.  This was used
to inject into the top of the mounting screw holes to seal
them completely, as they would not be needed with the
new deck plates installed.

A thicker epoxy mixture was needed to fill the core damage
area.  The same resin and hardener was mixed with 406 Colloidal Silica to create a
consistency between jelly and peanut butter.  This was forced into the opening a bit
at a time with a flat mixing stick (think tongue depressor).  It took several applications
of epoxy, a bit at a time, to completely seal the damaged area.  I made the mix a bit
thicker as the deeper parts of the voids were filled and the edge area was being
filled, to lessen dropping onto the newspapers below.

After the final bits of epoxy were applied and set, it was necessary to sand the inside
of the opening to remove irregular edges on the hardened epoxy and to remove the
excess material.  This didn't take long, and I soon was able to fit the deck plates into
the holes used by the old Dorade boxes.  I sanded smooth the deck around the
openings where the deck plates would be, and then cleaned the area with acetone
and allowed it to dry.  The final steps were to apply a generous portion of waterproof
caulking to the underside of the flange of the deck plates (I used BoatLife's LifeCaulk
for this), insert the deck plates, and fasten with mounting screws.

(It's best not to tighten the screws all the way at
first.  Give the caulk a day or so to set up, and
then complete the tightening.)

While the core repair for the new deck plates was
being done, I proceeded to remove the bow rail,
the bowsprit, forward toe rails, and the anchor
locker hatch.  All of these were in the way of
removing the old paint to prepare for repainting
the deck.  I also removed a portlight from the
main cabin with the idea of replacing the
age-crazed semi-transparent "lens" with new
material.  More on these subjects to come.
Refurbing - Dorade vent removal
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I'm describing the
deck repair in the
order it was done,
but the actual repair
took a few weeks of
elapsed time.  While
the core was going
through the drying
process, I continued
with tasks shown on
other pages.
One of the newly installed deck
plates is shown with a transparent
screw-in element.  Note that the six
screw holes for the Dorade box
have been filled with epoxy.
The vents have been removed from the Dorade
boxes in this photo and replaced with solid
screw-in elements, to prepare for a tropical storm.