'72: Are factory bonding strips "black 'glass"?

[Patricia Brown]

Hi everyone,

My '72 is a mix of old, standard "black 'glass" and SMC. I will be installing press molded, standard 'glass rear quarters. Did the factory make any bonding strips of SMC, or can I assume the bonding strips are all standard 'glass? If they're standard I can just use polyester glue for my new panels, but if the strips could at all possibly be SMC I'd better use epoxy. Wondering if the factory mixed-and-matched their bonding strip materials as they did the panels in '72.

Relatedly, my rear deck top panel is made of SMC. My new rear quarters will be of standard 'glass. If I use polyester glue it would hold the new quarters to the bonding strip just fine (assuming the factory bonding strip is also made of standard 'glass), but would there tend to be any seperation or cracking or problems where the polyester glue abutts the SMC top deck at the bonding seam?

Thank you,
Patricia

[Chuck S.]

Re: '72: Are factory bonding strips "black 'glass"

I don't think anyone can answer that question for any given car without seeing the bonding strips; but, it shouldn't be hard to identify the material once you have them visible.

As Wayne said before, if the bonding strips are polyester FRP, then you can use whichever adhesive on the material is appropriate. However, I would not depend on polyester adhesive to fill the gap between the two panels since it's adhesion to the SMC is questionable...I would default to the epoxy materials for the gap fill, or just use body filler.