Fiberglass panel adhesive question

[Touring4]

Hi!
I have a bus with the curved fiberglass panels. The panels were 90+% disconnected when I got it.. basically only held on by a handful of rusted off screws on the ends

The metal behind was filled with rust holes from leaks - I didn't realize it was possible to so poorly build a bus

Anyways, I'm wondering if anyone has ideas on what type of adhesive to use to reconnect the panels after getting the frame fixed up.

The paint store suggested I used the 3m panel epoxy, but as you can see in the pics (of the old adhesive) that sometimes the panel is tight against the metal, and sometimes there is a 1/4-1/2 inch gap filled by the stuff. Basically, the steel frame doesn't perfectly fit agains the panel, and the adhesive fills some gap.

Here's the epoxy adhesive: https://www.amazon.com/3M-08115-Pane...s%2C168&sr=8-3

In this article: https://www.assemblymag.com/articles...ailer-assembly
they used Loctite 5570 and H8600.

What do you think about the best adhesive for this?

Before:


Panel removed:


Inside the panel:



Close up of joints:

[rossvtaylor]

The epoxy panel bonding adhesive is good stuff. But I prefer and highly recommend the 3M 5200 Fast Cure, which is about as permanent as you can get...and it can bridge/fill 1/4-inch gaps easily. I don't know about 1/2-inch gaps...that's pretty big...but for short sections of larger gaps, with smaller gaps on either side, it should work.

There's a regular 5200 that takes 7 days to cure. I recommend you find the Fast Cure version for this.

[Touring4]

Thank you for sharing that, it looks like the right one for this!