So, despite the fact that I work this evening, I spent most of the morning doing work on the boat, putting in some additional supports on the loft, taking measurements......
Im in the midst of screwing in a brace when there's a POP and I drop about 5 feet......
okay, it was more like three inches, but it FELT like 5 feet.
One of the boards propping up the sides had simply popped off, shearing off the screws and allowing the middle of the boat to sag a couple of inches.
I of course freaked out, fearing the whole thing was about to crash to the ground, and leap off the boat. I grabbed my little bottle jack and some cribbing, jacked the boat back up, and rebraced the port side.
On investigation, our torrential rains had undermined a couple of the concrete blocks that were supporting the side abaft the port beam (and yes, I did just construct that sentence solely so I could use the word "abaft" :) ) I spent the better part of an hour resetting the supports all around the vessel and feel a bit better about things now, but two things stand out to me if you're doing this sort of project:
One is, these kinds of floating docks are intended to have the general support of the floatation spreading force across the vessel, not to be pinned up by only one or two stress points. We need to get this thing in the water as soon as possible and
Next time I build a smaller boat, no more than 8' wide, no longer than about 22 feet. If I need additional room Ill build a float for an addition and use the boat as a tug to handle it.
A level building space would have avoided a lot of this as well.