I talked to mike at F3A Unlimited a couple of days ago and he recommended starting at .75, Probably splitting hairs here due to angle machine acuracy but that's what I'll shoot for.
Anywhoo, I finally got to start building after not being able to for a while. First thing I did was the hinging. Unfortunately whoever worked on mine at the factory didn't give a rats az about precision. ALL of the holes were drilled crooked or off center, horns too. After I had opened them up enough to allow good geometry they were very loose. So I decided to try something different. I used Hysol as hinge and horn glue because it doesn't run. Worked great BTW. I used a fine sharpie to mark he centers of the hinges, I replaced the perfectly good stock hinge points with Robart ones just because I had some. I hinged both sides of the hinges at the same time, worked them back and forth to line up the hinges, made sure they were centered by adjusting the sharpie marks with an eXacto, taped them in place with little squares of cardboard to help align them top to bottom, and prayed. Worked out great! The hinge gaps required varied quite a bit as my surfaces had some warps and off angles but its done and everything is aligned and free, also I'll tape the gaps. Should be good.
