Section 21 Primed F-1202F Bulkhead flange and six F-1212L&R Step Rib flanges. Pg. 21-14 Step 3: Dimpled nutplate rivet holes in top flange of F-1202F Bulkhead. Step 5: Dimpled bottom holes in fwd. flg. of both outboard Step Ribs and corresponding holes in F-1202F Bulkhead. Ran into a problem dimpling the top flange of the center Step Ribs. My dimple die was too large to align with the holes in the flange (see photos). Ordered a small #30 dimple die from Avery Tools.
