BEDE - 4

Repairs:  5/12/2016

Right Wing - Upper Surface: 

Here is the damaged area with a ball-point for size reference.
Here is the damaged area with my initial cuts marked.  Sorry about the glare in the photos - I'll see if I can proceed without using the flash from now on.
After making the straight cuts, I used a sanding drum on the Dremel to eliminate any sharp or square corners.  (The white powder is a result of the sanding - it will all be removed.
We examined the material removed from the damaged area and found that it appears to be a single, thick  lamination.  I also spent a considerable amount of time evaluating that "scratch" descending away from the punctured area.  In the end I decided that we needed to remove the "scratch" too and so I marked out the cut-lines.
After completing all the cutting and sanding, I vacuumed the sanding dust from the area and from inside of the wing cavity.  (The joints in the vacuum system are taped so that none of the parts can become dislodged and fall into the wing.)
The next step is to make a piece of material for a patch to fit inside and to epoxy to the upper skin. In order to match the contour in the area which is going to be patched, we will lay-up a single layer of 7.5 oz. fiber glass on a piece of plastic on an adjoining section of the wing.  First a piece of plastic is taped to the wing skin; second a piece of fiberglass is cut large enough to cover the opening; and finally a piece of peel-ply is cut to place on top of the fiberglass.
The fiberglass was thoroughly wetted out with epoxy and then the peel-ply was placed on top and also wetted out.  Finally the excess epoxy was removed by squeeging.

We rolled up a paper towel and taped it on the bottom of the plastic in order to have a Damn to prevent any of the epoxy from running off the plastic onto the wing.

And now you can see the fiberglass and peel-ply curing at least over night on a section of the wing next to the damaged area to be patched.

The next step will be to cut the internal patch to the correct size and shape and epoxy it into position closing the hole.  The patch should be cut and shaped to overlap the hole by at least 3/4 inch on all sides.

Norman Tracing the shape of the opening to be repaired.  The wing itself acted as his "light table".
After tracing the opening, Norman added a 3/4 inch border all around the tracing.  The tracing will be sprayed with an adhesive and bonded to the patch material.  Then the template will be cut out from the patch material.  Sorry but the photo failed to capture the lines made on the paper.
The finished patch waiting for the tracing paper to be removed.  Next after some additional sanding and vacuuming we will maneuver the patch into the wing and bond it with epoxy to the underside of the top surface of the wing to support the rest of the patch work.