Yesterday’s temperatures were finally in the high 50s, and I was able to glass in the new section of engine bed. I went to Home Depot looking for lumber, and came home with an 8′ length of Douglas Fir 4 x 4. Douglas Fir is a well know boatbuilding wood, especially for spars, with plenty of resin to resist rot.
I began by measuring the space, and found that I needed a 9″ length roughly 3.5 inches wide, and 6+ inches tall at the forward end, tapering to slightly less than 3 inches tall at the after end. Obviously, the forward end was going to be comprised of two sections shaped to fit, set one on top of the other, and the after end was going to need a slight trimming to fit the profile. My apologies – at this point, I was focused on capitalizing on the warm weather, and didn’t plan out my photographs at all, so I don’t have any photos of the shaped blocks that made up the repair section.
At the boat, I mixed epoxy and painted every surface to be bonded with unthickened epoxy. Then I thickened epoxy, mostly with West system 404 for adhesion, and poured it into the void, making a bed of epoxy mush to set the blocks into. This took perhaps 6 ounces of resin and more than a cup of 404 to get the right consistency. I didn’t want it to flow once in place, so it was pretty thick. I set the foundation block in place, mixed more epoxy and 404, and filled all the voids around the sides of the block with it. Another batch gave me a good layer of mush for the top and transitional sections of the shape. I placed the smaller shaped section of fir on the forward end of the foundation block, completing the basic shape, then filled any abrupt angles with thickened epoxy to accommodate the glass cloth.
For glass I used 15 ounce biaxial glass tape 4 inches wide. I’m glad I didn’t use anything heavier, as this was difficult to wet out, and not very flexible where corners were concerned I think heavier would have been more unwieldy. I pre-cut all the pieces to shape, then wet them out and applied them to the newly glued in sections. The final result looked like this (again, please pardon the photos. These are from my low-quality phone).
I will wash this with water and a green scrubby, then grind down smooth and look for voids around the edges. After filling voids and sanding those smooth, it will be ready for paint.
Glassing the window I cut in the side of the bed, which you can see forward of the glassed in block, involved filling voids and edges with thickened epoxy, then wetting out the glass and laying it in until I had built up the thickness of the laminate again. If I were very concerned about strength, I would use one larger piece of glass to tie it all in with the surrounding laminate, but I’m here to tell you, that piece of glass isn’t going anywhere. It’s plenty strong just like that. Similar to above, I’ll grind it smooth, looking for voids, patch the voids, then sand again and paint.
My biggest concern with the glassing was to get all the exposed and new wood sealed and waterproof. I am confident that it will be impervious to water intrusion when I’m done. I also filled my test holes on the starboard side – this just involved injecting epoxy resin into the holes. There was some settling of the resin, and I need to repeat the injection to fill out the holes to the surface, this time with thickened epoxy.
This was an incredibly simple process. The material is so easy to work with – and mistakes are fixed easily by simply grinding out the error, and redoing it correctly – or at least the way you had intended it to be done. Everyone should be encouraged to attempt their own repairs if they have time. Time is the big factor. Expertise is the easy part.