: I am prepping the exterior of the Merganser for glassing. The kit
: instructions call for 80 grit sandpaper on the wood.Do you try to get the
: wood supersmooth both visually and tactile-ly (is this a real word???) Or
: just smooth to the touch, so that the glass lies easily on it? Should I do
: a second sanding with finer paper (120 grit) or would this be a waste of
: time best left till the post-glassing, pre-varnishing stage?

The general concensis is to sand to 120 grit and stop. Stopping at 80 grit could leave visible scratches.

: Also, before the sanding but after I planed the joints to radius the edges, I
: painted all the joints and pinholes with epoxy to seal any small exterior
: voids. (The panels were beveled earlier and most joints are tight, so I am
: not talking about filling large gaps between side-to-side panels.) I used
: a small amount of wood flour in the epoxy and now the stuff has left
: stains. I have sanded those areas so they feel smooth and continuous with
: the adjacent undarkened wood, but they still show as dark stains. How much
: will they show when glassed, and should I sand deeper to try to get rid of
: them? I assume I *can* sand them off entirely without going into the 2nd
: ply but am not sure.

Wet out the whole boat w/ epoxy prior to glassing. The new epoxy should blend in the already epoxied areas to the rest of the surface. Otherwise the boat could look blotchy/stained in the areas where there's already some epoxy cured in/on the wood surface. It only takes a couple of ounces of epoxy to do this and there's no effect on the yet-to-come glassing steps (well, you MIGHT use a tad less epoxy at that point but otherwise...).