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The craziness continues!

My continuing flirtation with Aviation:
I've purchased a 90% complete Mitchell U-2 Flying Wing!
(Which in Aviation math usually means, 90% is left to be done.)

Patching small "Dings" to the center section wing

I was aware of some "hanger rash", small dings in the wing's surface, which at the time of purchase I thought were minor.  Surprise, a couple of them were not so minor. 

Working on the smallest "Ding" which is on top of the wing not involved in the accident.
   
Initially this small break in the plywood skin looked like it was nothing more than a scratch or snag in the covering fabric.  But then I found the plywood below the fabric was broken and water damaged - probably by some heavy object falling on it.  The plywood which is wrapped around the leading edge of the wing is a structural element so it must be repaired.
   
I start by cutting out a circular hole around the damaged area.  Then I cut the fabric back away from the hole.
Before proceeding, I made a template of the finished hole so I can properly shape the patch.
 
This is the doubler which goes inside the wing to support the patch.  The little slot in the doubler allows me twist the larger doubler through the smaller hole.
   
Using Norm's little clamps again to hold the doubler while the epoxy cures.  Again,  the clamps need to be shimmed up tight - a noble use of old business cards!
   
Preparing to Epoxy the patch in place.
   
After being sure all new wood surfaces have been sealed with T-88, the patch was Epoxied into place and weighted down to hold the correct shape.
   
The patch didn't take the profile shape perfectly and will need some minor filling.
   
Norm just hates it when I take his picture but he does have to work to earn his lunch!

Here he is removing paint from around the patch in preparation for the fabric covering.

   
Working on the Second  "Mystery Ding" which is on the bottom of the Opposite wing
   
This is one of the original photos from the seller.  But it turned out to be a mystery "ding" because it is on the bottom of the wing on the opposite side of the aircraft, away from the accident damage!  And we didn't locate it for several weeks after returning to Colorado!
   
After opening up the "ding" we found that a rib had been effected and damaged.  It had been crushed slightly, concave and pulled away from the plywood skin.
   
I carefully cut away the damaged area of the rib and then sanded it.
   
Replacement pieces were cut out of foam and epoxied into place.  The repair foam is being held in place with Popsicle sticks. 
   
   

Working on the Third  "Ding" which is on the bottom of the wing damaged in the accident

   
This is one of the pre-purchase photos sent by the seller.  The damage looked superficial when I looked at it while loading up the plane in Oklahoma.  When I got it home and started poking around in earnest, I found that the underlying plywood was damaged more than I had thought - another major repair.
   
Sorry about the angle but this spot is on the bottom of the wing, very near the floor and it is hard to get a good angle for a photo.

But you can see how big of an area I had to cut out in order to remove all the damaged skin.  Fortunately no ribs were effected.

   
Before proceeding with the doublers, I cut out a template for the patch.
   
Then I Epoxied the first doubler and clamped it into place.
   
The next morning I removed the clamp and Epoxied the other 3 doublers in place with Norm's clamps and some more shims.

Yeah, that is a "real" airplane in the background.