26 April 2013

Water Line

After giving Cabin Boy's bottom and topsides 3 coats of oil-based white paint, it was time to tackle the last big project on the refit: applying bottom paint. I never got around to anti-fouling his bottom on my trip up the coast. This wasn't too bad a problem, mainly because we kept moving, and because I had time to pull him out and give him a good scrubbing any time the weeds got too thick. But this summer, good old Cabin Boy will be parked on a dinghy dock and will need some protection.

One problem: I had no waterline to draw to. How to paint one on a curving, lapstrake hull?

At one time, in the misty days of my youth, I might have been tempted to do something creative, like perhaps use a plastic hose filled with colored liquid to establish a waterline. It makes sense, right? If you take a long hose and attach it to bow and stern, and then fill hose so the water level comes right up to the waterline at both ends, then if you move one end around the boat, the water level should stay constant and show you exactly where the water line should be, right?

How Not To Draw A Waterline
Ha-ha-ha! Only a pathetically naive boatbuilder would try something like that. A more mature and experienced one would never waste half-a-day trying to get such a crazy scheme to work. No, he'd pull out his books before he pulled out half his hair, and look up the correct, proven, traditional way to tackle the job.

Naturally, that's what I did. (Helena, I told you to destroy those photos!!!)

Yes, the correct way to do this is illustrated in the photo below.  The two cross beams are level with the design LWL (load water line), fore and aft, as shown on the original plans. The cross beams (and the boat) are leveled using a bubble level.

Then a string is hung between the two beams. The ends of the string are weighted, in this case with two big shackles. If the two beams are at the LWL, then the straight line of the string is also at the LWL.

Move the two ends of the string so the string just touches the boat at one end. I stared in the stern. Draw a line under the string.

Then move the string so it bears on the next part of the hull, and continue drawing the line.

Drawing LWL -- actually, an inch above the waterline
Eventually, you will work your way around to the bow. Cabin Boy is a bit hollow in the bow, so you can't get the string to lie right on the hull in the bow, but it is easy enough to eye-ball the line and draw it in under the string.

Move string to hit different parts of boat... draw line under string
Once the line is penciled in, its time to tape. Because the waterline goes onto the second lap in the middle of the boat, you have to be pretty darn neat with your tape.

Tape showing line
After drawing and taping the waterline on the other side of the boat, you are ready to paint. I put on 3 coats of good bottom paint: Micron CSC. A quart was good for 3 coats.

The result? A fairly neat job, if I do say so myself.

Another look
Once the paint was dry, it was time to install the varnished inwales and outwales, cut ropes for the fenders, and otherwise prepare for launching.

Here he is on the town dock, ready to be officially re-splashed. A suitably-beautiful spring day was ordered up for the occasion.

Ready for launching
Looking pretty good...

Don't ask me why oarlocks are like that
After a lovely row across a very chilly Huntington Harbor, Cabin Boy was at last tied up in his summer berth... the dingy dock at the Ketewomoke Yacht Club.

If the club had a contest for best looking dinghy, I'm pretty sure he'd win.

On the Ketewomoke dingy dock

And that is the end of Cabin Boy's refit story. A long way from how he looked after his Big Adventure:

The day after sailing into Huntington Harbor

AFTER having his bottom scrubbed!

Next time, we turn to the Blue Moon's new galley...

Next Episode: When You're Ready


  1. He looks absolutely stunning. Very handsome!

    And very inspiring.


  3. Could not get the post. The images were EXTREMELY Large.

  4. Always wondered how to do that waterline thing Properly! As usual, it's pretty easy. (I don't want to talk about what I did, how long it took, OR how it came out.)

    1. I got this method from the Greg Rossel book. It was really easy.

  5. Thanks for the post. That line came out very nice.


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