So I'm dealing with door wood trim that's peeling away from the metal backing, trying to find the best adhesive to deal with heat in the summers and cold in the winters, was thinking construction adhesive but wondering if anyone has any other suggestions?

 

My experience with construction adhesive is that it's not a stand alone bonding agent. It works applied to floor joists before you screw down a sub-floor to prevent squeaks, but you have to use secondary fastening. With repairs such as you describe, best results usually require stripping away the old adhesive before applying new. Removing the entire panel and sanding off the old stuff might be more work than you want to do. So you could try some 2-part epoxy, such as JBWeld, on the separated area and see if you get a lasting fix. If it separates again, then do the full repair method.

 

That's an excellent suggestion, thank you!

 

Forgot one other point. No matter what type of adhesive you use, you need to apply some clamping pressure for a couple hours while the adhesive sets up. A door panel is a challenge, but you might try looping a cargo strap around the door with the window down. Use some towels or blankets to protect the paint and other surfaces. Cinch the strap snug, and then squeeze a wood block between the strap and the trim piece you're gluing. You don't need a lot of pressure -- just enough to keep the surfaces being glued in contact during curing. Good luck!

 

That won't be a problem, the current trim piece on my door panel is broken off, and I've ordered a replacement piece that's peeling away from the metal backing plate, so I'll be able to do the gluing before I replace it on the door