Preparing to Build
Preparing the Ribs
Two coats of Poly Brush were put on the rib capstrips to prepare them for the fabric. Prior to this work, all edges were smoothed with Super Fill and rivet heads that will fall under glued fabric were covered with anti-chafe tape.
Right Wing Top Fabric
The fabric was installed on the top of the wing in the same manner as the bottom. I spent a lot of time with an iron at 225 degrees removing wrinkles and bubbles from the leading and trailing edges. The inboard and outboard edges were wrapped around the end rib capstrips and glued. The entire wing was then heat shrunk with an iron at 250 degrees. This has prepared the cloth for rib lacing. The lacing will be done prior to the final heat shrinking at 300 degrees in order to avoid pulling the fabric away from the ribs on the concave bottom wing surface.
The metal flanges which are used to attach the fiberglass wingtips was installed using flush rivets at the outer end of the wing.
When the rib lacing was completed, the fabric was heat shrunk to its final tension. Then, the first coat of Polybrush was applied. This chemical is a pink colored liquid vinyl. It seals the fabric and provides a strong foundation upon which the other exterior coatings will be applied. Another strip of fabric (called the finishing tape) was bound to the fabric over each rib, false rib, trailing edge, and leading edge. Once everything was completed, two more coats of Polybrush were sprayed over each wing using a gravity feed HVLP paint gun.
Flight Control Covering
The empanage structures were covered with fabric in the same manner as the wings and fuselage. A single piece of fabric was used for each side of the horizontal stabilizer. Scraps were used with the rudder and elavator - overlap joints at both the leading and trailing edge. I purchased a roll of bias tape to use at all the curved areas. I also had to purchase an extra roll of 2 inch tape and an extra gallon of polybrush to complete this phase of the work.