Fiberglass Repair The Sailboat Hull

Article By Shorty


The daggerboard trunk was cracked on both ends, so I sanded it down pretty good and glassed in both ends again. I used several laters of glass with filler over top.

Next was that big hole. I had a couple of options -- first idea was to make a backup plate (from fiberglass) and put it inside, then pull on it with strings while sandwiching thickened epoxy so it would adhere to the inside of the hull. This is the more common method for fixing this type of problem, but this hole was on the bottom where nobody would be looking, and I didn't want to take all that time, so I went with an external repair instead.

First sanded down the edges, and pulled them together so they held the basic shape of the outside of the hull. I then put a few small dabs of thickened epoxy to sort of "tack" them into place, like welders do. After that cured, I could really goop on the thickened epoxy to fill the entire area. (this pic is of the big gooping of epoxy, before sanding).

I also filled in other parts of the hull that needed it, then sanded everything down.

The bow has had a number of previous repairs, I added to it by sanding and then adding a couple layers of fiberglass. Looks horrible here because you can see all the other repairs below, but after I sanded it and painted, it really looked (and was) solid. Much stronger than the original bow.

Here is a repair done in a hurry, I should have cleaned up the drips but had to leave it right after application. Several love bugs are trying to imoralize themselves by swimming in the epoxy, obviously they watched Jurrasic Park too many times. Came right off on the next sanding pass...

I did a few things and forgot to take pictures. The interior support was bugging me, there was a ton of flex when I sat in the cockpit. I wanted to do something to support it so I wouldn't be damaging the hull more every time I bounced up and down in her, so I decided to foam between the cockpit and the hull.

You can see a series of holes, there are 3 rows of them. I drilled these in the hull and then poured in self expanding foam. This foam then expanded and made a perfect support, it was very solid to sit on. Another round of filling in holes and sanding.

Finally I put a layer of fiberglass on the entire bottom which starts just aft of the trunk and goes to 6" from the stern.

Extra layers of glass over the big hole.