Typically we use twill tape laced in a zig zag between ribs to hold them from twisting between the spars. The tape is place half way between the spars. You start at the root end of the wing and go from the bottom of the root to the top of the next rib then back to the bottom of the next rib, etc., wrapping around the capstrip of each rib as you go. When you get to the wing tip you wrap around it and then keep going back to the top of the root rib, forming an "X" between each rib.
WACO did this by glueing a stick of the 1/4" x 3/8" capstrip wood, the length of the wing, on the inside of the rib capstrips. The drawing shows the stick 16 7/8" from the center of the rear spar to the center of the stick.
So far I've only done the piece on the bottom of the ribs out to the secondary strut. I need to complete the wing tip bow to finish this to the wing tip. I also need to figure out how to assure the saw horses don't break the strip along the upper cap strip. When the wing is setting upside down, and top of the spars are resting on the saw horses, the top stick would get broken. I need to modify my Cessna 140 wing stands to use with these wings. They hold the ends of the wing so you can rotate the wing to work on it.
My plan for the leading edge wood strip is to cut it from a piece of spruce 1 1/16" wide by 1/2" tall. I think I can get it to near net shape with 3 saw cuts. Then I'll glue it to the ribs and finish shaping it by hand on the wing.
Before I do that I'm going to get the lower wing, I started, up to this same point, then do the leading edge and wing tip for both wings at the same time.
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