Fiberglass to steel. Panel bond or glass it in?

[oldcarnut]

I'm getting to the place where I'll be attaching my fiberglass rear window plug to the body on my Superbird clone. I've heard some may glass it on and others panel bond. I don't want to get a bunch of cracking or other issues down the road.  I'm using real glass window so I will be beefing up the plug some beforehand.  What's your recommendations from past experiences with bonding glass to steel and the prep beforehand such as no paint bare steel or apply paint then bond.  I've got no experience with either bonding types.  I know I have to buy an applicator for the bond.  Any advice or experiences?

[b5blue]

  1st off the age of any cartridge product is critical! I bought a case of stuff and didn't find out it was old till too late, what a costly mess that was! That said I have used panel adhesive for steel to steel with outstanding results. The steel was both bare and in some cases coated with Eastwood Rust Encapsulator. Both being epoxy I would think fiberglass would be no issue but would contact 3M, Evercoat, Lords or Eastwood directly before buying. Some supply houses will lend the gun if you buy the stuff from them local.
  Pay attention to the overlap area required in the spec. I had to back plate some areas butted together rater than offset flange to fix what I was doing. (To get ample surface area.) Temp is critical working time, fast set in hot temps might not give you enough working time for a big run like you will be doing. Think about clamping...how are you going to hold everything in place? Many areas I used tiny steel framing screws that I removed after cure and plugged the holes with more panel adhesive. You can kinda flood the joints to get good fill and shave off what oozes out with a razor blade before full cure, I found the cheap knifes that normally have you snap off the end to get a new tip worked nicely to have a very sharp 5" blade.
Good luck!