Limber Holes

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November 2001 --

I've had the boat six months at this point, and am still working through
the high priority projects.

Maybe I'm a bit judgemental,
but I'd like to talk with the person who drilled these limber holes.

These are just holes drilled through the stringer. The stringer is two inches of plywood, glassed into the hull.
Naturally, there's a very wet hunk of plywood inside, just dying to get out.
It's well enclosed on all sides with
an impermeable case of fiberglass.

I need to dry out the stringer
and fix the limber holes.

I took a 1.5" hole saw and spade bit and enlarged the area to remove the seriously contaminated wood around the existing holes.

Then I drilled four holes from the top all the way down. The four holes will let the moisture escape up and out, and will also allow me to inject epoxy down into the new plugs. All the wood was wet, even at the very top. However, it wasn't rotten!

The black that you see is actually motor oil that soaked into the wood around the hole. When I bought the boat I had a local Perkins dealer work on the engine and he dumped a quart of used oil in the bilge. The Perkins is a good engine, but it's the wrong engine for this boat. In 2006 I replaced it.

Since this is happening at the same time as the whole
"Inadvertant Mast Step Replacement/Inadvertant Cabin Sole refinishing" period, I figure I'll repaint the bilges and everywhere I can reach.

That meant spending a day scrubbing with enzymes, followed by ugly chemicals to remove 20 years of crud, wearing a respirator and heavy gloves. But I got it all clean, and you can see the first coat of paint. I plan to sand and add another two coats of Interlux Bilgecoat. Note that I didn't put paint on the stringer, since I'm going to sand it down and add some fiberglass fabric before it's over.

At the same time, I drilled a number of holes into the stringer from the top, to allow water vapor to escape. Then I put a 125 watt heat lamp on the stringer. In the picture at left, it looks closer to the sides of the bilge than it really is... perspective is distorted a bit. I don't exactly have deep bilges...

This was a real neurotic moment! Call me crazy... but I read once that
melting your boat is a bad thing. I tested the lamp at home, then rebuilt the plug with a ceramic socket. I set it on the stringer, and watched it for a couple of hours to make sure nothing was getting too hot. Then, I turned around twice while driving home to go back and check it, adding the braces on the sides to make sure it couldn't fall over no matter what. Still, I had to drive down to the marina the next day to make sure I still had a boat.
No problems! After 24 hours, things are warm, but not even hot.

After two weeks it's very dry! My Handy Dremel Tool made short work of cleaning up around the holes. Originally I'd thought I'd just fill the holes with epoxy and drill new limber holes. But a
1.5 by 3 inch hole is a big mass of epoxy, and when it kicks off I'm afraid it will get too hot and cook, making it weak and possibly cracking it.

This was the easy way out! I took two 1 inch through hulls, which just barely fit in length, and had about 1/8" of space between the fitting and the wood. Using my Handy Dremel Tool, I cut off the flanges around the nuts so that they'd fit side by side. Then, using a superthick fast setting epoxy putty on the edges only, I screwed them on.

Each limber hole has two holes into it from the top (using one of those 12 inch long drill bits.) So I injected drippy epoxy paste into one hole, slowly, and let it surround the through hull fitting until it came back up the other hole.
No air bubbles!

Right about here I realized that there's no point in putting more glass on this stringer. The only way more glass would add value would be if I ground down to the hull on either side and tabbed the whole thing in. That would be wasted effort, since it's structurally fine just the way it is! So -- I'll just paint it.