Today I started by drilling the three seat back hinges to the right aft seat floor. I then fabricated the two F-637C seat bottom reinforcement angles only to find that I had already made them. That's what I get for laying off the project for over a month...
I then fabricated a seat back lower hinge. I carefully laid out and drilled the end holes, then used the rivet spacing fan to mark the rest. Instead of using the fan as a drill guide and risk enlarging the holes, I used the 3/32" transfer punch shown to mark the holes. There are only 7 intermediate holes so I only marked every other space. I will use this hinge as a template to drill the hinge for the other seat.
I finished the day by radiusing the outside vertex of the top stiffener angle. Tedious work!