Brief Description: Start final install of upper window
Figured out my approach to drill/updrill the aft edge of the upper window where it meets the upper fuselage skin. Instead of rivets, machine screws (AN3 size) are used wiith nuts and a cork strip between the window and fuselage skin.
Used masking tape to estimate the spacing if the screws, and used a light from underneath to align the tape with the very edge of the fuselage skin. I then made a mark for the exact spacing I wanted, followed by another mark to indicate 10mm from the edge of the fuse skin.
First drilled thru just the acrylic window, with a plastic bit, then used a regular metal bit to drill thru the fuselage skin. Updrilled to 5/32" using another acrylic bit then finalized with #12 acrylic bit to accomodate the machine screw.
Disassembled all, pulled the protective cover back from the edges and deburred all.
Applied the cork strip (adhesive) and drilled thru it with my #12 bit. Lifed up the aft edge to brush away any cork debris, then inserted the screws. Applied nuts to the underside with no washers as per plans. Snugged in place.
