Once all of the F705 bulkhead parts were match drilled I disassembled everything and then did a little countersinking. There are 2 nutplates on each of the side channels that needed to have their corresponding rivet holes countersunk. Also, there is one rivet on each of the doubler bars that needed to be countersunk. I screwed up here. For one thing, I drilled an extra hole in each of these doublers. These were in the joggle area and looked like they needed to be drilled in the plans but as it turns out, the hole were only to be in the long bar and the channel and not through the joggle in the doubler bars. Bummer. The second thing that I did wrong was countersink the one hole that needed to be countersunk in each doubler bar on the wrong side of the bar. Bummer again. I decided that since this is such a critical area where the rear wing spars will be bolted that I would replace both doubler bars. Another order to Van's. $6 something each. Not too bad...
