I was not happy with the smaller and larger hand tools for setting rivnuts and during the build of the tanks I had some spinning rivnuts which is annoying to fix. So time for improvement.
Interesting to read is this article: Kitplanes
TAF advices to use high strength Loctite, but I did some test and the result was a bit disappointing; adding Loctite did not prevent a spinning rivnut; actually there is no difference with or without Loctite.
I tried the suggestion the the article from Kitplanes and did a test and applied some JB Weld and let it cure for 24 hours.
The result was amazing, a M4 bolt will snap before the rivnuts spins:
I purchased a new tool for setting rivnuts: Astro Pneumatic Tool ADN14 Rivet Nut Drill Adapter Kit
The advantage of this tool is that you can use the torque limiting clutch on the cordless drill to apply a consistent and correct force.
The rudder box requires setting 6 M4 rivnuts, good moment to use the new tool and add JB Weld:
Rivnuts are in, so the box could be mounted to the rear fuselage (a piece of cardboard to prevent scratches):
While working on the rear fuselage I pulled the rivets for the step support brackets: