|1975 Dufour 27
Refit | Monday, November 24, 2008
I'd lined up some help for the day's work, and it's a good thing I did. Both installing the rubrail and the ports would have been exceedingly difficult alone. As it was, one job went better than expected, and the other less well than hoped, though both saw their way to successful completion this day.
We began with the aluminum rubrails, extruded, formed pieces that fit just over the hull-deck edge and extended down onto the hull. Originally, these had been installed with rivets, but I'd removed those and filled in the holes in the hull in anticipation of using machine screws to reattach the rail.
On each side, we dry-fit the rail, during which time I drilled and tapped all the new fastener holes in the hull, while the rail was in place. After removing the rail again, I applied a heavy bead of sealant along the top edge, where the extruded curve of the rail's lip would rest, and at all the fastener locations; the original installation had contained no sealant in either location that I could determine. Then, we replaced the rail and installed all the fasteners--1/4-20 x 1" flat head machine screws. As I mentioned earlier, I was rather tied to this particular fastener size--larger than I might have otherwise chosen--because of some pre-existing holes and countersinks in the rail from earlier repair/refastening attempts.
With each rail in place, we cleaned up the excess sealant, and the job was complete. The job went very smoothly and without issue, though it still took several hours to complete.
After lunch, it was time to install the two hull ports and a similarly-constructed deck skylight in the head. Earlier, I'd precut the port blanks from new material, using the old ports as templates, and , with the port temporarily held in place, marked off the paper on the inside (bearing) surface so I could remove the paper where the material would rest against the flange for bedding. I left the paper on the rest of the port surface to protect it during installation, and taped around the outer edge of the openings to protect the hull, since I planned to let the sealant cure before cleaning up most of the excess.
Confident, therefore, in the ports' ability to actually fit, I proceeded with the installation by applying sealant (Life-Seal in this case, a silicone/polyurethane blend) to the bearing flange, after which we attempted to install the ports using the original barrel nuts and screws from the inside, which threaded into the barrel nuts.
This was where the problems began. Firstly, the fastener holes didn't line up as well as I'd expected, despite my having sighted several of the holes during the test fit. So I ended up having to slightly re-drill most of the holes as we went. Worse, aligning the first hole pushed the port blank just far enough forward that the forward end wouldn't sit down flush in the opening, forcing me to remove it and trim the blank just a bit. Fortunately, I was able to accomplish this and get the port back in place without having to clean up all the newly-applied sealant.
With considerable effort, therefore, we managed to get the first port completely and successfully installed. Using the lessons learned on the first side, we then dry-fit the second port completely, using all fasteners, in order to prevent the same issues, after which the second installation went more smoothly.
Finally ,we installed the skylight on deck, located above the head. Again, we dry-fit this, and I made some minor modifications to the size of the blank as a result. Final installation was relatively straightforward.
In between the
various other jobs, I moved the jackstands and applied barrier coat and,
finally at the end of the day, bottom paint to complete the work on the