I finished flanging the lightening holes and then fit the center reinforcement and drilled it to the forward channel. The rear flange won’t be drilled to the skin until the frame is clamped back to the fuselage.
The side reinforcements are much trickier. The flanges placed around the holes severely distort them, and it takes quite a while to bend them even close to the final shape.
After much fiddling, I drilled the forward flanges to the channel. I then tweaked the aft flanges so they lay flat against the skin. I need to do a little trimming along the inner edge (along the black line that’s partly visible on the left) to provide some clearance from the hinge supports. The reinforcements needed to be shifted inward so that one hole that’s shared with existing structure will have sufficient edge distance.
