Late start tonight so not a lot of progress.
Tonight was mainly a prep work night. First up was drawing new lines on top of the roof to define the two inch overhang. From yesterday you'll remember that I discovered that the forward part of the cabin is narrower than the rear. I thought about leaving the top a consistent width all the way back, be decided that would look funny, thus the new lines.
Next was a lot of thought about how the ribs will go. These will be easier to install, especially the ones that run up the sides as there's no funky curve to deal with. :-) I've decided to run the ribs over the top and space them 15-7/8" apart. That will allow me to get maximum usage out of the foam insulation by cutting it in 16" wide strips and getting a pressure fit between the ribs.
I built the first rib at the back running from side edge to side edge, temporarily screwing it down at both ends. Next I ran a single 1" strip along the new lines on either side to give me a definite set of points to work off when measuring to cut to length the ribs.
Then I very carefully measured and marked for those 15-7/8" gaps.
Finally I picked up all the strips off the floor and counted them out. Turns out I'm several short, so the table saw will get some use tomorrow.
Following the cutting of the strips I'll start the installation of the ribs. Not sure how many I'll get finished as each one is a custom length.
2.5 Hours