I also fabricated doublers from .040 stock for the side channels in order to open more holes through them - the parts come with only two holes, and even though Van's says it's ok to open a third, I'll rest easier with this reinforced:
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| Doublers cut to size |
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| Doublers match-drilled |
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| Fully-drilled doublers for having more holes passing conduits and air lines |
The goal is to run 3 conduits through each side, pitot+AoA on the left and static air on the right.
I also, again per advice from VAF, countersunk the two holes on each of the forward center section bulkhead side channels that will need to de riveted double-flush:
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| Flange holes (top center) were countersunk for double-flush rivets |
Next, I need to prime all these parts and start riveting.
Time lapse:
Total mid-fuselage bulkhead time: 33.3h