Wing, part 2

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After dry-fitting the wing ribs, leading and trailing edges, and bottom spar I glue them together. Following this step, and after the glue had dried, I glued the top spar, wing tips, and center-wing 1/16" balsa covering. The wing tips are a simple 1"x1" balsa block formed and sanded into shape.


Next came the tricky part of sanding the center edges of the wing to fit the dihedral angle, and then accurately cut a slot through the spars for the dihedral brace. The rib on both center-facing edges are of 5/32" balsa so that there is enough material to sand down at an angle. I raised the wing tip to half the dihedral angle and used a wide sanding block to sand the edges perpendicular to work bench edge. The slot for the dihedral brace was created by cutting through the spars' length with a mini hacksaw, and then carefully widening the slot to fit the 1/16" plywood brace.

Both wing halves glued with epoxy.


Next, I made room for installing the aileron servo. This is a 9 gram servo that fits nicely beneath the top balsa wing covering. I had to cut a gap in the center rib, so I made sure I did not epoxy this area. In order to reinforce the center I added two half-ribs (trailing edge to spar) on both sides of the servo and made sure I left room to route the servo's wire harness.

Next I covered the bottom of the wing with 1/16" balsa sheets, and glued the servo holder (1/16" plywood) with epoxy.





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