Wings 49, total 512 - Scuffing and Cleaning rear Spar Parts

Just to properly document the reason for my lack of work on the project all last week, here are couple of pics of the old shed doors and frame remnants:

I completed the work on the new priming table yesterday. I used some chicken wire that I still had lying around from when I made the slammer table that I used for priming many of the empennage parts. Note that I would recommend that you use the small square type of wire as this is much easier to work with than the real chicket wire. The challenge was trying to get it tight enough to support the weight of several ribs and other parts. I used the 1x2x8s to make in internal frame, clamped everything together, and used 1 1/4 inch wood screws to secure the frame to the cardboard.

Then I had some small 1/2 inch hex head sheet metal screws that I still had to drill 3/32 (#40) pilot holes for. I started down the long side, securing the wire under each of the screws in such a way that I would be able to pull on the remaining wire to stretch it as much as possible to tighten it up as I attached it each of the other three sides of the box. These screws were inserted on the top side of the 1x2 wood frame. After it was done, everything was pretty tight, but my hands were sore from all the pulling and tugging I did. After the long side was done, I secured one short side, and then the long side on the other side, and thenfinally the short side on the opposite end pf the box. I continued to pull and stretch the wire diagonally to take up the slack as I drilled and secured each screw to the frame. Then I trimmed the excess wire from the edges and called it good.

And finally a shot of the support brackets and doublers for the rear spar all scuffed with the scotch brite pad, sand paper, etc., and cleaned with acetone and a microfiber towel. The doubler forks presented me with an interesting problem, in that they still showed all the cut lines along the inside edges of each fork, and I had no easy way of getting to these insude edges with a scotch brite wheel to debur these ragged cut lines. The last place I want to see cracks starting to appear is on the support brackets for the wing spars. So I really wanted to try to clean these up somehow. Solution - that small 1/4 inch dremel sanding wheel. I ran it across the inside edges of each fork to remove the obvious cut lines from the factory, then went over the edges again with 220 to 320 aluminum oxide sandpaper to smooth everything out. Seemed to work pretty well.

Now I need to get both rear spars scuffed and cleaned - I think I am going to need more scotch brite pads. Actually there are still some skin attach holes that I need to drill to final size and dimple per the plans, because you cannot get a squeezer in the proper position to dimple them after the support brackets are riveted to the spar, because the thickness of the doubler covers the hole, so these must be done ahead of time.