The ribs on the left side are now glued to the main spar. Both ends of the ribs had to be sanded to an angle: 3 degrees on the leading end, and 1 degree on the spar end. In addition, the chord line had to be maintained, while keeping the proper measurement between the leading edge strip and spar at each station. After taking off the clamps, I was disappointed to see a 2 mm dip in the leading edge line near the middle. Then it occurred to me the main spar might have some sag, since it is supported only on the ends. I stretched a string, and found 2 mm sag, which I corrected with a 2 x 4 prop. A few ribs are a mm or less too short, so I glued in some shims on the leading edge. After sanding this down, the leading edge strip will be ready to glue in place.
The tips of the ribs are supported with a temporary board on the back side of the jig (lower surface of the wing), and with blocks of pine glued to the board so the ribs can't be pushed to one side or the other. Without this support, the ribs could be quite easily broken until the leading edge strip is glued in.
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