The first pic is just because the spar box looks nice at this point.
The plans call out hard points from 2024 T3 alloy which I imported via Spruce. It was cheaper and easier than buying locally which is a bit sad. These become where the main bolts go through to hold the wings on.
I cut the pieces to size on my bandsaw and curved one end as required. Then all the sanding marks were removed and finally scotchbrite scrubbing.
Its pretty easy to alodine with gloves and plenty of ventilation. The metal is preped first in some pretty nasty stuff and then washed with water. Next a minute or so in the Alodine, rinse with water and let it air dry.
