View Full Version : Rubbing compound on plastic bumper?

03-26-2004, 11:59 PM
brand new car and some F* who doesn't know how to drive, hit my car while it was parked and ran away ...

The PLASTIC bumper is chipped ... can it be repaired using "chip repair" techniques such as fill, sand, rubbing compound, wax, etc??


03-27-2004, 04:29 PM

03-28-2004, 10:31 AM
rubbing compound is too abrasive chip repair paint is usually solid pigment and needs no clear coat,which yours probably has.so just use the paint and see how it looks.

03-28-2004, 11:32 AM
The only way to properly repair paint chips is to have the whole bumper painted. You can use touch up paint, but it will never match properly.

03-28-2004, 06:38 PM
is it plastic bumper that is the same color as the car? or a black one that is textured. YOu can repair either one, just make sure you are suing proper plastic fillers, and primers

03-28-2004, 06:43 PM
plastic bumper is the same color as my car ... what kind of plastic filler should I be looking for .. and where can I find them?

03-30-2004, 02:33 PM
how big is the swipe? You're probably better off getting the whole thing re painted, but if you insist on doing it yourself, might as well get you to do it right.

Find out what kind of plastic your bumper is, you usually have to take off the part to find a symbol for the plastic on the back, if you don't know what kind of plastic it is. Take a razor and scrape a small chunk of plastic off it where it is not visible (preferably on the back of the bumper) and do a water test. Drop it in a glass of water, and let me know if it floats or not.

If it sinks, it's thermoset plastic, meaning you need adhesion promoter for the bumper before you attempt to paint the swipe or else the paint will just fall off. If it floats, it's thermoplastic. Let me know I'll tell you what products you'll need to get it done right (it won't look professional but it will stick until you get it done by a body shop). What ride of yours got the swipe?

03-31-2004, 02:07 AM
thx serusnak ... very detailed info ...

Its a brand new V8 Limited 4runner ... about 3 big scratches approx 1inch long on a corner ... I was planning to slowly fill it with touch up and then sand it down ... just something a bit better looking than right now .. right now its just looks like a few tear marks which are very noticeable thou

04-05-2004, 11:52 PM
Yes, but it's important that you find out what kind of plastic it is. Because if it is thermoplastic, it can be repeatedly softened and reshaped by heating with no change in their chem makeup. They are weldable with a plastic welder or they can be adhesively repaired.

Otherwise, thermoset plastics- when you heat it and reshape, you can't reshape it again meaning you'll be fucked. They are usually repaired with flexible parts repair materials.

You mean, you were planning on filling it up with touch up paint? You could try that, though you will need to roughen the inside of the cuts up before putting in anything, at least it'll give whatever you put in some grip, with or without the adhesion promoter.

Because I don't know what kind of plastic you've got there, best bet is to use chemical adhesive bonding, 3m sells those and they are often used as filler before applying the final repair material. Get a 2 part adhesive system, it looks like two tubes sharing one tube.

Roughen the surface up, and fill in the cuts with the stuff, and remember you'll only have about two minutes to smooth it out before it sets. You can either choose to sand it down to shape it or leave it, until you can get it fixed properly. It won't look the greatest and it will be the color of black so unless you repaint it to cover it up till you get it fixed, it'll be pretty noticeable. Use adhesion promoter on the repair area before you repaint.

Like I said, I don't know what kind of plastic you've got there or how deep the cut is, best bet for you is just to have it get done professionally.

Good luck.... heh.