The Bubble Doors utilize the same fabrication method as Plexiglas Skylights – the same skylights as typically seen in school gymnasiums and factory spaces.  Luckily I had a local company who made these Skylights.  They had the equipment and know how to make my Bubble Doors and instructed me on how to make the tooling.

The first thing was to weld together a steel door frame that followed the contour of the airframes door opening.  I used a 1″ square 4130 steel tube and carefully tack welded the door frame inside the airframes frame.  With one of the wings attached I could determine if the future Gull Wing type Bubble Doors would interfere with the bottom side of the wing when it was raised.  I also  designed the latching method and gas lift spring locations needed to open and close the doors.   After I finish welded both left and right steel door frames I then began to build the wooden molds around the front and back sides of each door frame.