Top wing

I started with building the top wing then the bottom wing, and included some picture and comments as I progressed with this first step. I followed the exact same process when building the bottom wing.

For each wing I traced and cut the set of four LE and four TE sheeting according templates. I made the templates out of packaging cardboard. The top-wing templates are visible in top right of this picture. The bottom sheeting (3 pieces) of each wing panel include the LE, TE, and wing root sheet that I glued together to form a single piece. 



Closeup of magnets holding 1/16" balsa sheeting.



Spar and ribs.



Left wing with-top sheeting attached with clothes pins. The top sheeting was glued in three stages: TE then LE, and finally wing tip. I used water to dampen the the top sheet, mainly LE and wing tip, to help form and curve the sheet to the ribs. The plans call for the top sheeting to have the same dimensions as the bottom sheeting. I found that if I extended the overall width by 1/8" to account for the top curvature, then it was easier to manage the task and trim/sand later.



Right wing panel getting ready while left wing panel top sheeting dries at the back. The plans only have the left panel, so I mirror-printed the wing section of the plans to get the right panel. Outerzone also posted the mirror images.



A 10 degree dihedral is in place, after which the right wing panel sheeting will be glues in place. I built the wings around the dihedral brace because I did not find a good method to insert and glue the brace after the wing panels where completed and covered.


Complete wing ready for sanding.


I am fairly happy with the results. The instructions for constructing the wing were a bit vague, but after rereading them carefully it was apparent that I missed an important point: the bottom sheet of a wing panel must be firmly pinned to a flat surface while the top sheet is glue on. I managed to develop a small warp in the wing tips because when the top sheet dried it pulled the wing tips up a bit. This will not be an issue to fix, but I could have avoided it in the first place.

Anyway, I'll start the bottom wing and this time I'll change the build process a bit. First, I will remember to pin the bottom sheet down while gluing on the top sheet. Second, I am going to glue the top sheet in sections: LE, TE, then wing root. I'll be fitting each section into place individually, holding them magnetically, instead of gluing it as one piece held with clothes pins.


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