Several tasks were done to the fuselage bottom skin.
First was removing the plastic where the rivets go that connect the skin with the main spar. These rivets will be the stainless steel rivets according SB0014. To prevent galvanic corrosion I will follow the same procedure as the wings. First Alodine, then 2K epoxy primer and set the rivets with tank sealant. I used the Alodine pen:
2 coats of Alodine followed by the primer:
To do a good test fit, I riveted the transponder antenna doubler to the stringers:
Test fit to the top floor skin:
Transponder antenna doubler in place:
One 4 mm hole was missing, this was an easy fix:
3 holes on either side needed upsizing to 4.1 mm:
Last task was de-burring, de-greasing and shooting the primer:
