My neighbor Sean loaned me his laser level to re-check the level on my strongback, and even gave me a tutorial on how to use it:Here I am looking at the laser dot on the measuring tape:
I was reasonably happy with the existing level considering that I'm working on a dirt base. The entire strongback was at most 5mm out of level across the entire length, measured at each of the 4"x4" beam mounting points. Using the laser level and the adjustable saddles on my pier blocks, this was trivial to correct.
Next up was mounting the frames, working backward from frame #12. Here is frames 4 thru 12, looking aft:
This is a forward-looking shot, with all frames but #1 mounted:
The plywood I'm using is cheap 3/4" construction plywood (the good stuff costs too much, and I don't want to use particle board outside). While working I noticed that many of the frames had lots of visible voids along the batten mounting edges. So I finished the evening off by mixing a quick batch of high-density putty and filled all of the voids in, to help the batten screws hold better.
Tomorrow I'll start mounting battens. I am still undecided if I will plank and laminate the hull half in two portions, or try to do it all at once. (Obviously I need to think fast, if I'm mounting battens tomorrow!).