Regarding the vacuum seal issue with wing tubes: I drilled a very small hole in the center of the wing tube (1/16") and a 1/8" hole in the center of the wing socket. The holes are exactly on top when the wings are installed. Put your wing tube into the wing with the hole on top, slide into the fuse and mount your other wing. No trapped air and the holes don't seem to affect affect strength. If you'drathernot drill holes in the center then just put 2 small holes in the wings (on the bottom of the wings) through the tubes like you would do if you were using screws at the end of the wing tubes to hold the wings on.

John Pavlick
Team Black Magic, Tech-Aero Designs