I played Santa to myself and got a new, more powerful 6" random orbital sander made by Bosch, plus a variable speed polisher by Makita. My old 5" Makita palm sander, which is lighter, will be used for vertical surfaces and tighter spots. In retrospect I would have bought the Festools line of power tools from the start of this boat-building project, as a kit. Once you use good tools on a big project, you appreciate the better quality stuff.
Christmas day was spent sanding the deck again, while the weather was cooperating. It will go back days of rain again in the near future but I'm hoping to get the sanding done and out of the way by the weekend, and hopefully if the Awlgrip primer I ordered arrives on time, I can start priming this weekend (we're supposed to have sunny weather, and in the 70s.)
One of the problems I'm having is that the previously-applied primer is peeling off certain sections of the deck where there's a yellow material beneath. Not sure what that is, perhaps some sort of filler/fairing compound? Whatever it is, it absorbs moisture and causes things painted over it to peel off. In a way, leaving the boat for 15 months with the primer on was a good idea because it exposed such weaknesses -- had I painted over this stuff, the paint would have peeled off too and I would have had to completely re-paint the deck in a short while. So I'm glad I caught it. But now I have to chisel away the peeling primer and sand off the yellow stuff until I get to bare fiberglass.
I am also finding damaged gelcoat that needs addressing.