My instrument surround has suffered the same failure that a lot of them apparently have...the two lower mounting points fell apart and the screws have nothing to grab ahold of. Notice in the 4th pic that I also broke one of the rear tabs removing the surround. I've just applied some JB Weld to try and repair that. Fingers crossed it holds.

https://imgur.com/a/qN2h2YL

Anyway, I know the tried and true repair for the lower mounts is to just use 1-5/8" drywall screws, which I'm prepared to do. But I thought I'd at least try a proper fix first, to see if I can keep the countersunk look. I was about to just try adding some globs of JBW on the back of those holes, roughly shape them, let em dry, then drill them out. But I think JBW dries too brittle for this.

Is there a better product (Bondo, JB Plastic Weld, etc.) that's more flexible and sturdy for this type of work? And while I'm at it, should I undo the JBW on that tab and use something better there, as well?

Anyone else tried a similar fix? Cheers.

 

I have been repairing old plastics from all year cars/manufacturers for 20+ years. JBWELD is by far a superior product for this.

Jb weld is stronger than the surrounding plastic, providing you're using the correct jb weld.

if you're using the two part gray/black that takes a few hours to dry, then you have the correct jb. There is jb that you roll together, this gets harder but I feel it's not good for small jobs.
There is also a quick dry jb that isnt as hard as the gray/black.

what I do, wash my item in dawn dish soap. Rinse, let dry. Wrap the area to be repaired with the shiny side of aluminum, Reynolds wrap. Mix your jb. Put the jb weld onto the broken piece and mould that aluminum to make a better cast and to hold the JB where you want it. Areas that dont "need, to be detailed can be left thicker as this will strengthen your repair.

another trick is to drill small holes near your break and allow the jb to flow into those holes as well thus making the whole repair even stronger.

use a straw and put the straw through the hole to be repaired. Smaller holes, use a small spray can straw. Form your jb around the straws. The jb will adhere to the straw but if the straw is a good fit in the hole the straw wont matter.

let dry for the rest of the day then drill your holes, shape and mould.

 

Thanks for the reply. This is all super helpful. Yeah, the JBW I used on that tab is the KwikSet, unfortunately. But I've also got some standard 4-6 hour stuff. I'll try the mounting point fix with that. Using a straw to cast the hole is a great idea, I'll definitely try that, if I can find something the right width.

But I'm not fully following your use of the aluminum foil. Can you explain further? Is that something I'd do when just using the JBW to build up new screw holes? Sorry...just not following you there.

Cheers.

 

so for example...

let's say you're repairing a flat piece of plastic with a hole in it...or a pipe.

Fold the foil a couple times to add strength to the foil or buy thick foil. I normally use Reynolds. The JB doesnt usually stick to the shiny side. I've made repairs and pulled the foil right off the JB without leaving any foil behind. It provides a nice smooth surface that you may not have to modify much.

so you tape the foil over the hole on the flat piece and then fill the area with jb. Let dry. Remove foil. You should have a reasonably flat repair.

on a pipe, you mould the foil to the contour of the pipe, fill the repair with jb and let dry.

for things with texture, if your good, you can rub the foil over the texture which transfers it to the foil. Put the textured foil over the repair and fill with jb. If you do it evenly, your texture should fill in the repair and leave you with a textured repair with possibly the line where the jb meets the plastic.
use a dremel, carefully to remove any imperfections. While it may not be perfect, some rustoleum plastic paint can usually cover many of the lines etc if you take them down some.

I hope I clarified, if not let me know and I'll elaborate some more.

 

Ahh gotcha, yeah that makes perfect sense. Thanks!

 

I wonder if the JB weld will work on the center console for the window switch panel.
The screw mounts are fragile and broke off so the panel has nothing to mount to. I shoved a large empty medicine bottle behind the panel just so it wouldn't fall inward.

 

of course it will. If you buy the long set JB it will be even stronger.

JB Weld and a dremel are two of my favorite tools to fix just about anything.