Refreshing Interior Plastic

[JSanford]

When I pulled back the drapes to get to my rear speakers, I discovered my rear speaker grills appear to have been painted white. This is really odd since the plastic rear cap is a putty color. The back side of the speaker grills are bare putty colored plastic. I thought perhaps they had oxidized like some old plastic does, but I think it is paint. I have fixed chalky oxidized plastics by using a heat gun in the past, but when I tried that on the speaker grills they burned and melted (you can see the damage in the lower left corner). I tried a non-toxic paint stripper, but by itself it didn't have much effect. I used a palm sander with a scotchbrite style pad with the paint stripper, which had moderate effect. Lastly I got pretty aggressive with a stiff wire brush I got about 98% down to the bast putty plastic.

Yes, yes, I know, the speakers are hidden behind the drapes and no one is ever going to see them, but I am anal like that and will lie awake at night with those thing taunting me ?

Anyone else had this issue or know of a good way to strip paint off plastic?

Here is the one I have done and the other one that I have not done yet, the back side is untouched.

 

[tmsnyder]

Seems like I remember there being a product / cleaner / whitener that was activated by sunlight, for getting the old yellowed plastic white again. I'd never do it personally but remember seeing someone was doing it. Too high a risk of breaking that old fragile plastic imo. My plan is to clean and spray it all with a reasonable off white color, not a bright white spray bomb though.

 

[JSanford]

Hydrogen peroxide, in the form of Salon Care 40 Cream Developer, works great for restoring old plastic that has turned yellow from UV exposure. I have had great results turning old clock radio cabinets white by coating with Salon Care and then putting them in a plastic bag in the sun.

I guess it is possible that the white on my speaker grills is some sort of UV damage. A round of Salon Care can't hurt I guess.

 

[tmsnyder]

You might have to whiten the plastic that wasn't painted, and then color match paint to re-coat the one that was painted in order to get it to match. Maybe?

 

[JBurt]

It looks to me like your speaker covers have been painted. My unpainted speaker covers and headliners have turned a darker brown with age.
Anyway, here is a link to reversing UV damage on ABS.

Reversing UV Damage on ABS Plastic

Reversing UV Damage on ABS Plastic: Like so many others, I have been in love with Star Wars since I first saw the movies as a child. I also have a lifelong love for costuming. These loves finally came together in the mid 2000's when I first met some members of the 501st Legion at a …

www.instructables.com

I plan on using this technique on my headliners when I get to that part of my list. I don't know if it actually reconditions the plastic so it's not so brittle, but I doubt it.

 

[JSanford]

You can skip all the other ingredients in "retrobrite" and just use straight Salon Care 40, or any other 40% peroxide hair "bleach."

My plastic headliner caps are more of a putty color. I don't think they were bright white to begin with.

 

[JSanford]

A several hour soak in a product called "Motsenbocker's Lift Off Spray Paint and Graffiti Remover" followed by scrubbing with a soft wire brush got most all of the white paint off.

Now the speaker grills blend in better with the plastic walls. Of course one I put the curtains back you won't see any of it LOL

 

[Kevin F]

Were the walls originally white or where they a cream color? I always thought they were white and browned out due to sunlight over time?

 

[JSanford]

Were the walls originally white or where they a cream color? I always thought they were white and browned out due to sunlight over time?

Yes, the plastic ages and gets yellow. It is interesting that the speaker grills were originally putty colored and had to be painted white, where the plastic walls were white and have become putty colored. It is much easier for me to make the speaker grills match the walls than vice versa!

I am pleased with the outcome.