by mike cunningham » Sun May 14, 2017 1:34 pm
Wow, what an experience. Now have three of the four fixed ports replaced. I have not used any adhesive to attach the port frames to the hull. I used butyl tape exclusively. I have compressed the seal using the interior frames which are screwed into the exterior frame and do a fine job of compressing the frame against the butyl and establishing a bulletproof water seal. I really like this approach because removal clean up and and window replacement next time around is vastly simplified.
A couple of additional comments. As mentioned, I used dow 795 and butyl to adhere and seal the glass to the frame. The 795 (and other sealants) was a pain due to the curing of material in the nozzle between window installs which, in my case, were several weeks apart. I had some 4 mil pastry bags which I use for epoxy mixing and application and thought I would try squirting the sealant into the pastry bag, cut the bag tip to an opening size of my liking and do my thing. When a sealing job is completed the bag and residue go in the trash.
This worked great! The ability to control the bead was fantastic, you don't need to deal with a large unwieldy sealant applicator and you can practice your pastry making while you are at it. All this four about 15 cents a bag. Available on Amazon and elsewhere.
When the windows were sealed to frames but before installing frames in boat I tested waterproofness by putting the frames in the garage up on a couple of sawhorses then filled the frame with water (external surfaces) The frame will hold about a gallon this way so you get a pretty good test. I left them for 24 hours and watched for any dripping. Frames 1 and 3 were good but 2 had a leak. Solved this by applying some pressure to the window in order to cause the butyl to compress a bit more and form the seal. Worked like a champ.
After install I spent about 5 minutes per window driving water at them with a hose spray nozzle with special attention to the sealed edges at window and hull. Looked good.
Final test can only be done at sea with water on deck and the hull flexing in waves so we will see how that goes.The Singlehanded Farallons in coming up on the 20th and that is always a good test. I'll report back on success.... or lack thereof.