Initial Prep (Debur, Trim, Drill, and Cut)
3/1/23 - 1.9h
3/3/23 - 2.1h
The flap, like all the other build steps, starts with preparing parts for assembly. The first job is to lay out a 4-hole pattern in the joggle of a left hinge bracket, drill the 4 holes, and then use that hinge bracket as a template for the other three left hinge brackets. Note that the right hinge brackets do not get drilled in this step.

Preparation of the nose ribs comes next. The faceted curved forward-edge flanges get buffed with a 6” Scotch Brite Cut-and-Polish wheel to “minimize the tendency for them to appear faceted instead of curved.” I didn't need to flute any of the ribs since they were all straight, so I moved directly to deburring the holes and edges.

The final parts that get some attention in this step are the rod-end assembly doublers. The doublers don't have any complex curves or crevices to complicate deburring, and I did most of the edge deburring with the 6” Scotch Brite Cut-and-Polish wheel since it was already out to buff the nose rib flanges. After I deburred the doublers, I cleco'd one each to the outside of a left and right nose rib to form the outboard rod end rib assemblies. There is a nut-plate pattern in the doubler that is used to match drill the holes in the ribs. The center hole of the nut-plate pattern is also match drilled with a 1/4" drill bit.
[Hole and Edge Deburring Tools, #40 Drill, 1/4" Drill, Bench Grinder with 6” Scotch Brite Cut-and-Polish Wheel]

Final Prep (Dimple, Countersink, and Shape)
3/2/23 - 0.7h
3/3/23 - 0.3h
The final task for this step was to countersink the nut-plate holes in the doublers flush on the exterior side. The rod end rib subassemblies are then disassembled to clean and debur the holes, and then reassembled with the clecos inside the flange of the ribs.
[Bench Grinder with 6” Scotch Brite Cut-and-Polish Wheel, Microstop Countersink Cage with #40 Countersink Cage]