Although the original fixed ports are in amazingly good condition, they are finally showing internal crazing and broken corner tips at the screw holes. Time to replace them. My originals have a gasket which has worked great. 35 years and no leaks. I understand the gaskets are no longer available and many had trouble with them. They apparently were not used on many boats.
I have looked through the old forums and can't seem to find any mention of using VHB tape for installing windows. From what I've read it seems it would be a very good solution. It is double stick tape on a relatively thick closed cell foam - I plan to use .06" thick version. That should handle the shear of thermal expansion of the acrylic. I need to measure to verify but I think I have about 1/2" of overlap so my plan is to use 1/4" wide tape on the inside of the overlap, then mask off and fill the remaining outer edge gap with Dow 795. The VHB would maintain a gap between the window and deck so the 795 isn't squeezed out. I do not plan to use any screws.
Has anyone used VHB with good (or bad!) results? I'd appreciate feedback.
Also - I found where Maine Sail says to use cast acrylic. His comments are usually very well justified. But my research indicates that for this application extruded should be as good or better. Anyone have experience in this regard?
I have looked through the old forums and can't seem to find any mention of using VHB tape for installing windows. From what I've read it seems it would be a very good solution. It is double stick tape on a relatively thick closed cell foam - I plan to use .06" thick version. That should handle the shear of thermal expansion of the acrylic. I need to measure to verify but I think I have about 1/2" of overlap so my plan is to use 1/4" wide tape on the inside of the overlap, then mask off and fill the remaining outer edge gap with Dow 795. The VHB would maintain a gap between the window and deck so the 795 isn't squeezed out. I do not plan to use any screws.
Has anyone used VHB with good (or bad!) results? I'd appreciate feedback.
Also - I found where Maine Sail says to use cast acrylic. His comments are usually very well justified. But my research indicates that for this application extruded should be as good or better. Anyone have experience in this regard?
