How would I reattach drooping headliner without taking it out, replacing it, or... thumbtacks

[Roxy_the77diplomat]

For my base model 77' diplomat coupe, if that changes anything

 

[Mikes5thAve]

Unless you want to add bows across the ceiling to hold it up you don't. It's come down because the foam under the material breaks down. You could try replacing the material whole it's in the car but that would make a pretty big mess and gravity might not let the glue work properly.

 

[Duke5A]

Without doing any of the aforementioned? Flip the car upside down.

 

[Roxy_the77diplomat]

Without doing any of the aforementioned? Flip the car upside down.

 

[AMC Diplomat]

For my base model 77' diplomat coupe, if that changes anything

View attachment 56010

You need the @Camtron solution

Link: Post in thread 'Sagging headliner' Sagging headliner

 

[Oldiron440]

I’ve done this before a couple of times, remove the trim from the edges of the headliner then remove the fabric and scrape off the foam. Clean the cardboard base and then you could apply either a thin layer of foam first then a layer of fabric or a new layer of fabric that matches your interior. You can pull out the cardboard base and then do the work outside the car which is easier but you risk damaging the base removing and installing it especially if you have never done it before.
To adhere foam to the base you need a spray adhesive 3M makes one, you spray the base and the foam let it set up and then apply it to each other. Then to apply the fabric to either the base or the foam just spray the base or the foam and then apply the fabric before it fully sets up.

If you try this in the car a good shop vac is necessary and I like having compressed air so I can blow everything out.

Good luck and have fun with it, you can get creative if you like with the fabric.

 

[Camtron]

For what it’s worth; those twist pins are still holding just fine, lmfao.
It’s a bigger/tedious job to do it right. Whenever you get to it, the prep work of the surfaces will make or break a lot of your effort. Get a good adhesive remover and clean everything up before you spray any new glue down, get a legit headliner fabric that will have foam backing attached from manufacturer and if you can swing the extra cash, may as well put some insulation on the sheet metal before you reinstall everything.
Fun pattern may help cover up little mistakes when all said and done. There’s a little bit of a learning curve but nothing you shouldn’t be able to figure out with a couple tries. Start with the small pillar trim pieces to get a feel for it.

 

[Roxy_the77diplomat]

Sounds like a plan @Camtron & @Oldiron440 I'll probably do it here in a couple weeks, I'll let you know how it went when I do get'er done

 

[Dippy Daddy]

Sounds like a plan @Camtron & @Oldiron440 I'll probably do it here in a couple weeks, I'll let you know how it went when I do get'er done

Hey Roxy, did you ever replace your headliner fabric? I need to do this on my '86 Fifth, and the headliner in my '84 Diplomat parts car is just about perfect. I'm going to try pulling it out of the Diplomat and maybe dyeing it dark red to match the Fifth. The Dip has a light gray interior. I understand you have to take out the seats to get the headliner & backing out in one piece. Never done this, so I'll probably wait until the warm weather returns to northern Ohio.