Originally Posted by PNW_Steve
For sealing, I used brushable auto body seam sealer and 3M 5200.
When I was patching holes in the floor, I used 3M 560 Polyurethane Adhesive Sealant. That has worked well. It makes sense to use a liquidy sealant rather than a solid.
Why did you use both the seam sealer and 5200? Do you have a build thread that showed this process?
The thing I was thinking about the butyl tape is that you could put the rivets through the tape and it would seal the holes. I guess you could do that with the sealant, it would just have to be done while wet.