Today, I started on the first step of wing construction. Which unfortuneately is a long job. Countersinking the main spar flange for nut plates. Appraently there is 128 nut plates on the main spars, which require three countersunk holes appiece, two for the rivets and one for the screw. So I wanted to get a running start at the long task.
I started by creating a doubler to fit below the flange and keep my countersink cutter vertical. Then I setting my countersink cage to have the rivets sit at or just a shade lower than flush on a practice piece of material. Once satisfied with that, I had to first match drill all the rivet holes to let the countersink guide slip into the holes.
After all the prep work was done, I began countersinking the rivet holes, and checking them with a spare 3-8 rivet. The process went faily slowly. I would cleco up a part of a row, countersink and check one side, then cleco another length of row, and swap the previously drilled holes to the other side of the platenut (nutplates). Just doing one flange took quite a while. So I stopped for the night after getting one flange done.