We planned to do the port and starboard rail installation in 3 steps:
At this point the goals are to make sure there aren’t any serious high or low spots in how the rail mates with the deck as well as to mark the locations of the fastener holes in the toe rails. Except for some reinforcement at the bow and in the area of the genoa track, the old rails had fasteners about every 14 inches, so we decided to stick with that.
Before doing the test fit I went below and meticulously recorded the relative location of every bulkhead or other obstruction. I then marked these locations on deck so we wouldn’t inadvertently position a through bolt where we wouldn’t be able to secure it from below.
Next, we fit the rail to the deck, fixed gaps by slightly sanding the bottom of the rail on one side or the other of the deck-hull joint, and refitting until we were happy with it overall.
Finally, we marked the location of the fastener holes in the top of the rail, making sure to avoid bulkheads and other obstructions. We used my tabletop drill press to get nice, straight holes (I don’t trust myself using a handheld drill for this), and a high-quality forstner bit with a 1/4” pilot bit sized to fit our fasteners. Except for the genoa track, I prefer slotted pan-head bolts to phillips because I think they’re less likely to strip if you ever have to really torque them. The bow-most piece required some adjustments on the drill press because the profile is angled out at that point, and the larger timber requires longer bolts.
The genoa track was a bit of an exception. My track takes 3/16” flathead machine bolts every 4”, no forstner bit, but countersunk for whatever sealant goes between the track and the toe rail (we’re planning on using butyl tape to seal the track).
(to be continued…)