With the third coat of finish paint on the coach roof, it was time to begin the installation of the new portlights. Froonie's original non-opening portlights had simply fallen into a state of disrepair - some 43 years of life had taken its toll on the aluminum frames and acrylic glass. The frames were powdered and generally disintegrating around the fastener holes, the gaskets were extremely dry and brittle, and the glass was...well, less than transparent. I found a pair of non-opening portlights at a local marine chandlery that had some age to them, but had never been installed. I had the original non-opening portlights with me while inspecting the new ones, and found that I would have to make some modification to the rough opening. I would also have to drill and tap for new fasteners - which as I write this has been completed. In the end, the price was far too good to pass up, so I made the purchase.
My first first order of business was to create a template of the inside frame dimension - the portion of the portlight that would define the rough opening. I do not have a picture to illustrate in this post, but will provide a better visual explanation in upcoming posts. With the template created, I centered it over the existing smaller opening created for the original non-opening portlights. I traced the template onto the cabin side to prepare for cut out.
Using my cordless Ryobi spiral saw, I opened up the rough opening to accommodate the new, larger non-opening portlights. What appears to be a box on the interior is in fact a box - I taped an empty box over the rough opening to catch the fine dust and fiberglass shards created by use of the spiral saw. With 90% of the interior completed, I was attempting to prevent more clean-up - the box worked perfectly.
...and the dry-fit.
Due to the slight convex curve of the cabin sides, and wanting to prevent water intrusion through large gaps in which the polysulfide may fail, I decided to fill the larger fore and aft voids with thickened epoxy. I removed the new ports from their newly fitted rough openings, and roughed-up the interior of the outer flange. Roughing the surface of the flange would provide for the best mechanical bond surface for the epoxy. I then taped the cabin sides under and surrounding the portions of the flange to be worked with epoxy - protecting the cabin surface and preventing the epoxy from bonding to it. Next, I wiped down the sanding residue from the port flanges and then began to mix epoxy. I used West System epoxy with 407 Low-Density filler and 406 Colloidal Silica as the thickening agents. After the epoxy was ready to use, I reinstalled the ports, taping in place to hold firmly in position as the epoxy kicked. Once the ports were in position, I used a tongue depressor to push and pack the thickened mixture in and under the flanges, and created a smooth fillet.
After the epoxy had kicked and fully cured, I removed the ports and cleaned the surrounding surfaces of the cabin sides. I then sanded the epoxy fillets to prepare for final installation and bedding in polysulfide. Results below...again, a dry-fit. (yes, that is non-skid applied)
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