I was a bit reluctant to forge ahead on the centre section until I hear back from Van’s so I decided to move onto the electric aileron trim assembly.
The first step is to drill a couple of holes in the plastic to #10 for mounting holes. This seems relatively straight forward however experience in drilling the flap mounting blocks has taught me to go slow and be certain that everything is square.
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Next the plans have you notch the top of the plastic. Turns out this isn’t exactly easy. I ended up figuring out by a lot of trial and error that 120 grit sandpaper wrapped around a drill bit on the drill press would allow me to “sand” a perfect notch into the plastic. The trick was to clamp a guide on the drill press base that would allow the drill bit to stay in one place and not have the piece wander.