Once the short carlins are secure, the longer ones fit in notches in the bulkheads, a notch in the mid-frame, and end abutted to the short carlins. Through the middle section of the boat, these carlins define the edge of the decking.
Fitting them in place was a bit fussy. On the 1:1 version, there are all sorts of clamps that might be used. Not so at this scale. I ended up devising a clamp made up of a short board with notches in each side. Wedging the board between clamp and carlin did the trick.
We can see the painted watertight compartment in this picture.
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