rbappelbaum

Although I have done a few centerboards and rudders lately it has been a while since I used an epoxy/graphite mixture on the bottom of a small boat. I was never able to get the mixture to flatten out like paint but the slight waviness was acceptable. This time it was bad and had runs. The runs were probably from adding another coat too soon but the whole application was very uneven and I am not sure why. A day later I sanded off the runs, washed the area and wiped it down with alcohol. The next day I add a single coat and it looks worse, although with less runs. I was using the Raka slow hardener and the temperature was in the upper 70’s deg. F. I used about one teaspoon of graphite per 3 oz. batch. I would like to blame it on the cheap foam brush I used. (I usually use a section of foam roller to spread.) I am open to suggestions on the proper application of an epoxy/graphite mixture.

Pictures of centerboard trunk.

The only thing harder than building a centerboard trunk is building a replacement. I found that the original builder hadn't followed the instructions very closely. But it was necessary to use some of the old trunk dimensions in order for it to fit back in this boat. I believe that the trunk rot was caused by the failure to glass the external seam between the trunk and hull. The whole process took about a year and a half. There were delays for weather and medical issues. There was a lot of trial fitting and sanding. I had help the day I glassed the trunk to the inside of the hull but the rest was a solo effort. A few weeks ago I got the trunk and cockpit sole painted and the hardware reinstalled. I had one really nice five hour sail in 10-15 knots. Then I hurt my back. Now it over 90 degrees so I probably won't get back in the water until fall.

I have cleaned up the area around the centerboard hole and found the hull and keel batten to be in good shape. I'm cutting a template for the trunk side out of that cheap thin ply found at Lowe's. (I call it door skin, but don't know the proper name.) I noticed on the plan a curved dashed line 1/8 " at the top edge of the trunk. Anybody know what that is about?

Yes, I have a Harbor Freight oscillating multi tool. I used it, a pull saw and a few other things. The centerboard trunk is out and I have started cleaning up the edges of the whole. How were the screws from inside of the trunk into the keel batten installed? I had to use pliers to get them out.

I have uncovered rot all the way to the bottom of the trunk. It appears that all that is left in that area is one ply of the 3/8” plywood with the glass epoxy glued to it (very flexible). The hull seems okay. I don't think the inside of the trunk to hull joint has a layer of glass tape as I can see heads of screws going into the keel batten. I'm over my head here. It is likely that most of the bottom edge of the centerboard trunk is as rotten as Hamlet's Denmark. It not likely that I can successfully clean out the space between the keel batten and the glass inside the trunk and slip in new wood (although the other side of the trunk would not have that problem). Anyway, this would put me back to a whole new centerboard trunk. Looks like that will require removing the thwarts, trunk cap, mizzen step and mid bulkhead just to get the trunk out. Anything else? Still thinking about stripping and burning the hull, and starting on a new boat maybe a CS17 mkII

The boat is Lapwing #5 and I was told that it was the 2nd one completed.

I bought the Lapwing in 2012 and (with the exception of two) she has spent every night dry on a trailer mostly in a garage. I suspect that the centerboard trunk was not made of marine grade plywood. I have pulled the centerboard, wrapped it in package tape and reinserted it to maintain the space. I am still scraping paint looking for more rot. Looks like I am going to have to cut away the taped seam between the centerboard trunk and hull. I am not sure what to do if the rot extends under the mizzen bulkhead. After cutting out the bad wood I plan to fill in with 4mm Okoume, glass and epoxy which I have on hand. If that goes well, I will add a new layer of 4mm plywood on the outside of the trunk and and make a new taped seam between trunk and hull. This is going to take a while. Thanks for all the comments.

Here are the pictures of the damage. First picture, port side, is about 40 sq in. and looks the worst. The other two are on the starboard side. The middle picture damaged area is only about 10 sq. in. The last one is the biggest, about 50 sq. in. Thanks for the tip about Git-Rot. Will 16oz be enough? Online it was cheaper at Jamestown than West Marine.

I am guessing that after 0 replies in 2 days that my boat is doomed and nobody wants to tell me. So I will probably slap a little epoxy on the exposed parts and sail her until the centerboard trunk falls out. I might also scab an additional layer of plywood over the existing sides of the trunk hoping to extend the life of the boat a little longer.

I have had a leak in the centerboard cap of my Lapwing since I got it. External caulking was not effective so I decided to seal it internally with epoxy before my first spring sail. In the process, I realized the centerboard needed work. It was worn down to bare wood in one place caused by a slight warp. After repairing and reinstalling the centerboard I began cleaning the inside of the boat. This is when I was reminded of the bubble I had seen in the paint on the side of the centerboard trunk. Well it turned out to be covering rot. I have now uncovered about a square foot of damage in three separate areas on the trunk and my spring sailing is looking doubtful. I suspect that replacing the whole trunk is beyond my skills. So I am considering stabilizing the areas with epoxy, adding scraps of fiberglass to the deeper parts, filling in with thickened epoxy and then sanding and painting. I should note that the trunk has epoxy and fiberglass in the inside but not on the outside. There is probably more rot near the base of the trunk behind the seam with the hull. I don't see how to get to this without ripping out the whole thing. Is this a viable plan? Any suggestions?

I have recently added a 55 lb thrust trolling motor on my Lapwing 16 with a single battery in the bow. It has work out so far. Robert

Thanks for the input, especially the pictures of Dawn Patrol.

Last year I decided that the CS15 was the right boat for me and I bought a set of plans. Before I started building, I found Lapwing 16 #5 for sale on Sailing Texas and couldn't resist. After my fourth sail, which was the first in winds of 12-15 mph, I noticed cracks in mizzen mast step. I am considering cutting out the whole thing and installing a new stronger one. I am open to suggestions on how to proceed. Has anyone else had a similar failure?

Sounds like good advice. I like the model idea.