Rot in Bulkhead

August 2005 - In July I replaced the bizarre aft deck tangs because they leaked and I discovered rot in the bulkhead.

In addition to having them made bigger, they're longer so that they'll have an extra hole to extend into fresh wood.
Only the port side leaked.

On the other side (inside the galley cabinet) I left the newly installed tang in place to help support the veneer, but slid a piece of wax paper under it so that I don't accidentally epoxy the tang to the bulkhead. The white stuff is just some Lifecaulk from when the new tang was installed.

Then I painted the area with thin west system epoxy. It soaked into the edges really well.
It took four pumps worth of epoxy before the wood wouldn't soak up any more.

The port side leaked because the tang was in the wrong place. Someone cut the slot and then realized it was right on top of the support for the quarterberth shelf. So the tang was just bolted through the shelf support, and it didn't seat properly.

I pulled the shelf off,
which is okay because I've always intended to make something nicer.

Here you can see how the bolts (there's only one left on) went through the bracket, right on the edge. You can also see the hole from the old galley AC plug, which was removed during the rewiring of the port AC run.

You *can't* see the rot. It's inside the bulkhead.

My first and best idea was just to drill small holes at the top and inject the whole area with penetrating epoxy, but I wasn't sure I'd saturate the whole area, and since it's vertical I was afraid that it would leak back out.

It turns out I was wrong, and penetrating epoxy would have been the perfect solution.

I should listen to my own advice.

The rot was more extensive than expected. In the pic to the left, it's difficult to see how the depth varies.

I cut through the veneer with a utility knife, and removed most of the rot with my fingers, then scraped a bit with a hollow fid
(hey, whatever's handy.)

I was *very* careful
not to break through the back layer of veneer,
as that would make the project much bigger.

Penetrating epoxy would have soaked into the dry, rotten wood perfectly, killing the spores and making
it solid enough for external reinforcement.
However, it's too late.

I'd already made a reinforcing plate of teak veneer marine ply, with teak trim on the visible edges.

After the final layer of putty filler
was applied to the bulkhead void,
the reinforcement was covered with epoxy
and set into place.

I used
super thick epoxy
and colloidal silica
putty to fill the space.
Because I didn't
want it to overheat
when it kicked,
I had to build it up in three layers,
waiting a couple of hours between layers so each previous layer would kick. I suppose I could have laid a little fabric in here for strength, but all I really want is a nice solid material that won't compress when I crank down on the bolts. Strength is provided by the "patch" of marine ply.

I had masked the area off with tape before starting this little project.

A few small screws hold it in place while the epoxy cures.

It covers up the old hole from the old AC outlet as well.

(Note that the vinyl liner on the hull
has completely fallen off, since the foam rubber insulation layer has disintegrated over time.
It's time to deal with that;
I'm tired of looking at it.)

To avoid damaging the finish on the bulkhead and the reinforcing plate, I cleaned everything up
with "Replacetone" from Tap Plastics.
Acetone would have been very destructive to the wood finish.

Replacetone is also safe to use on skin,
if you accidentally get epoxy on the hands or in the hair.
It doesn't emulsify the epoxy like solvents, but it makes the epoxy congeal so that it can be wiped up with a clean rag.

A week later, after the epoxy was fully cured, I stuck the bolts in. This should be good and strong.

After I finish fixing up the ugly interior of the hull, where the vinyl liner has disintegrated, I'll attach the new clothes cabinet that will hide all this stuff.

I really like this wrench. It's a combination crescent wrench and vice grips. Once you have the wrench set, it locks down on the nut or bolt really tight. It makes it a lot easier to clamp one side down and then go tighten up the other side.

Inside the galley cabinet, it isn't very pretty.
Some epoxy putty seeped through cracks in the veneer. However, this is so far back that it can't be seen, and there are a bunch of ugly hoses in that corner too.
I'll live with it.