Rivet nuts and access panels

[DND]

I find myself needing access to the fuel pump via behind the passenger seat and wanting access to the tunnel with the cabling et. al. running through it.
So I plan to replace the rivets with rivet nuts and screw/bolt the panels back into place for easier access.
My questions are:

Should I use aluminum or steel rivet nuts?
Are rivet nuts sufficient or should I use something stronger like plus nuts?

[DND]

I should clarify, with regards to the fuel pump, I'll have to cut an access hatch, not remove the whole panel.

[flynntuna]

ok I was going to say that just tap the frame and use button head screws , but since your cutting an Access hole I'd use aluminum rivenuts in the aluminum panel

[STiPWRD]

I used aluminum rivnuts all over the place (including at the rear firewall) and haven't had any issues. I would imagine steel rivnuts are a bit tougher to install (since steel is 3X stiffer than aluminum) and are more prone to galling with SS fasteners. FFR supplies you with a box of aluminum 1/4-20 rivnuts with the kit.

[mikeinatlanta]

Since you asked for opinions. Rivnuts and other such fasteners are for blind locations with no back side access. If you have access to both side of the metal a more appropriate fastener would be a nut plate. IMO, rivnuts and other blind fasteners in non blind locations are not indicative of a quality build.

95724

[Mitch Wright]

I second the nut plates, I have used them on anyplace that I had access to the back of the panel to install them.

[Scrmblr2]

Since you asked for opinions. Rivnuts and other such fasteners are for blind locations with no back side access. If you have access to both side of the metal a more appropriate fastener would be a nut plate. IMO, rivnuts and other blind fasteners in non blind locations are not indicative of a quality build.

95724

Where might I find these nut plates? I am getting close to being mounting my body panels and am investigating the best way to have the body panels attached but easily removable. I have been exploring dais fasteners and well nuts… but have been unwilling to comment due to the strength of fiberglass. I am also investigating pan buttonhead screws as an option when securing to the frame.

[Kodiak]

Aircraft spruce have them but for install You will also need ms470AD3-3 button head or ms426AD3-2 to -3 counter sunk solid rivets that you need to form a shop head on . Aluminum rivnuts will be fine with the low torque on the small fasteners either is fine.