January 31, 2011

Last week while browsing through some other sailing blogs, I ran across someone who had a Peterson 44 with leaking ports. It seems my speculation about the shortcomings of ports installed with trim rings was right on. Trim rings can hide a multitude of sins. They not only necessitate a weaker installation because the port isn't through bolted through the entire thickness of the cabin wall (Don't want any of those ugly nuts and washers to show, you know!), they hide bad cutouts, poor sealant application and other shoddy work. From http://www.sailblogs.com/member/yachtemerald/ : "I took the trim rings off the outside and discovered the horrors of voids and badly installed portholes, no wonder they leaked!" Also tends to confirm my reservations about boats made in Taiwan: what you can see is done beautifully; what you can't see may be shoddy. You need to watch them being built and specify rigging and perhaps other critical metal fittings carefully. Caveat emptor! (No offense to you owners of Taiwan boats....)Makes my installation look pretty clean!
Just in case you thought all I did during the week was Web surf, I also started on the job of rebuilding the two teak hatches over the main saloon. A couple of months back I had resealed the bases and added some neoprene gasketing, which greatly diminished the leaks, but didn’t eliminate them. Small amounts of water were migrating to the inside of the frame and dripping into the cabin. Although the sealant around the plexiglass looked intact, obviously it wasn’t. The way the hatch had been designed and built, with the plexiglass inset into the top edge of the frame, any water making its way past the sealant would have to flow to the inside.
I decided to correct that problem by cutting off the rim on the top of the frame, leaving the top edge flat, and use a larger (and thicker) sheet of plex that would go all the way to the outside edge of the frame. That would make it simple to use the preferred butyl tape as the seal as well as make it much more likely that, even with an imperfect seal, water would flow harmlessly off the outer edge rather than into the cabin. To eliminate another potential source of water intrusion, I considered mounting the plex to the frame using anodized angle aluminum. That way the mounting screws could be located on the sides and there would be no screw holes in the top surface. The angle aluminum would be on all four sides of the frame to secure the plex, but I would leave a couple of gaps on the lower edge (the hatches slope down toward the outside of the deck) to allow water to drain off the top easily and completely. The problem with this approach was that the mounting screws could not be used to hold the butyl in compression, which is critical to a good seal. In addition, the corners created by the aluminum would be sharp, not a good thing on a boat. So after a little vacillation, I abandoned the aluminum trim idea.
When I dismantled the hatches in the shop, it was obvious where the water had come in. Its path left dark stains in the wood and stained the pink sealant gray.
The rest of this post will be much briefer than usual. I spent several hours writing a longer one and lost a couple of hours work due to a disasterous accidental key stroke. Needless to say, I was very upset and frustrated, and just didn't have the heart to try to recreate it all. Besides, you might like the truncated style better. It's still got all the pictures and maybe they tell enough of the story. Let me know.

Saturday I went to the boat and completed the glass work and weatherstripping for rectifying the leaks in the cockpit side lockers, installed new and more secure dorade cowl vents (the old ones could be knocked off), and off-loaded a bunch of gear that I will not use. Sunday I went to a special tai chi seminar in the morning and spent the afternoon working on reinforcing and rebuilding the teak hatches per the plans previously outlined. Narrowly missed being hit by shrapnel while sawing through an old bronze screw.

I'm afraid that's it for this week.