sealing cabin at deck joint

[jaykimball]

I have a boat with a teak cabin and a plywood deck. The previous owner replaced the old deck with new plywood, and then applied a fiberglass epoxy layer on top. The fiberglass comes up to the edge of the cabin, and then he tacked in some teak wood shoe molding bedded in what looks like Sikkaflex. Needless to say the seam is leaking in spots.

I am thinking of pulling the molding and cleaning out the bedding material. Any suggestions on how to redo the union of cabin to deck to insure water tightness, good looks and low maintenance?

In other boats, have seen what looks like a bead of some sealant applied to form a gently curved seal. It is a dark grey material and seems to set up firmly. It didn't feel rubbery when pushed, but still had a sense of flex and elasticity.

All comments welcome.

Thanks, jay

[Art Read]

Bump... (Seems a good question. I'm surprised the bedded trim didn't work better though. Isn't that a fairly common practice? Perhaps just poorly executed in this case?)

[cbob]

Jay, If the new plywood deck , when covered with glass and epoxy, had been run under the cabin sides and the cabin sides set down in epoxy on the glass, would have been pretty leal proof, which is why some deck to cabin sides don't have moulding. Now the moulding is there and the glass on the deck terminates at the cabin sides, you could remove the moulding, remove paint, glue, goop, from the glass for about an inch out, all the way aroundclean up the cabin sides similarly, up as high as the moulding, run a strip of glass along/around this entire joint, say if the moulding is 3/4 inch, up the cabin side about 1/2 inch, and outwards on the deck the same, shape the faying surfaces of the moulding so that the upper and outer edges are in contact with the cabin sides and deck and put it back, and there. This is only for leak stopping/sealing purposes, and would add little or no structural strength. Luck with this. cbob

[warthog5]

cbob's way is pretty much how I'd do it.
But I'd make a nice fillet around the joint and glass over it.
Without seeing it, I would paint the new glass to match the floor.

[jaykimball]

Gents, thanks for the helpful comments.

Cbob, from your first sentence, I am thinking what I should do is just pop the cabin, and dress up the glass around the perimeter and epoxy the cabin to the glass. Is that optimal in your mind? I was thinking about removing the cabin, applying a thin (perhaps 3/8" wood edge that the cabin would sit upon, but bring the glass over that before replacing the cabin. That way the water coming down the side falls past the cabin joint and sits ob the deck, 3/8" below.

warthog5, Would you describe the fillet idea in more detail?

Let me know what you think.

Thanks, jay

[warthog5]

In the pix below you will see the gray area at the junction of the panels. This is formed using epoxy/microballons and a little cabisol in it. The cross section would look like a 1/4 round image.

http://www.troutwagon.com/Nautical/SwampWitch/images/fb88d3c4.jpg

It creates a smooth transion for fiberglass to lay smooth. I would suggest using a +45/-45 Db fiberglass tape for this.

It will give a very strong joint,

[cbob]

Jay, Not knowing the size of your cabin, boat etc. all I can do is describe how mine was built 45 years ago. Cabin (trunk) sides about 15 ft long, 1" mahogany, finished bright, 5' across forward. The deck is 3/4" exterior df ply. In way of the cabin, there are partial deck beams, The entire deck is covered with glass and polyester resin. The deck, with the trunk sides sitting on top, comes inboard from the sides a couple of inches, faced off, forming a narrow stowage place familiarly referred to as the gutter, where small things end up, glasses, pencils flashlights, parrallel rulers etc. There is no moulding on the inside or outside. About 20+ years ago, after noticing some sisterships (boats) having moulding, indicating a problem like yours, I headed off this problem, I think, of leakage by carefully dribbling CPES around the inside of the gutter with the boat listed somewhat to the side being dribbled, couldn't list the boat forward to get gravitational help on the forward face, however. Removing my cabin would be some kind of a job! again, cbob