Hey guys...I am wet sanding my bumpers and I was wondering what everyone fills in the imperfections with. I got some pretty big dings and chips to fill in? Do you guys recommend fiberglass or just bondo for a good fill? I am excited this is kind of my last thing to prep before the car goes into be painted, but I don't want to take any shortcuts. Thanks

 

when I did my bumper covers I sanded the area all the way down to the plastic, then cleaned with wax/grease remover, sprayed on adhesion promoter such as bulldog or 3M #5907, the filled in the gouges with Evercoat's poly-flex glazing putty and sanded til smooth....I also used this method to shave the rocker emblems and nose emblem.....just make sure you sand it nice and smooth......bondo and glass won't really stick well to the plastic and also becomes too brittle.

 

ohh alright thanks. I got a huge tube of poly putty that will work out good. I had read about that bulldog stuff on another thread. My brother is painting the car in his auto body class and the teacher told him the high build primer will work good on the plastic. Is this true or should I look to get that bulldog ahesive or 3m stuff?

 

I used the adhesion promoter at the repair spots and on the entire cover before each step....so before the poly-flex, then sanded, then adhesion promoter, then flexible primer, then sanded, then adhesion promoter, then paint

 

The thing is that you want something that will flex with the bumper or when the bumper flexes (and it does flex), it will pop out and take paint off with it. You may find that taking the paint all the way down to the bare urethane will help with the gouges, but some WILL be in the cover for some reason.

 

oh alrightyy...thanks guys I was in the progress of sanding to the urethane.

 

Wash panel with soap and water. Dish soap is recomended for its ability to remove grease. Just use basic dish soap, no scented or "soft hands". Block your old paint with around a 150 grit, as the lows (dings/scratches) work out progress grits in 100 grit steps. Eg. 150, 220, 320, for primer 320 is sufficient. You can go to bare plastic if you want however, (1) its more work (unless you have catastrophic paint failer) and offers no benefits, (2) you run the risk of making the plastic have burs, which you may fight later. It should be noted that nothing more aggresive than 50 grit should be used in plastic repair. For imperfections that need filler, Evercoat "poly-flex" glaze. Glaze will stick to anything, plastic, metal, paint/clear (scuffed). Adhesion promoter is required when applying product to bare plastic. Note that adhesion promoter is applied with a "mist coat" and not a "full wet coat". A good primer to use is Epoxy. Epoxy will stick to anything, and anything will stick to epoxy (exept acid primers). Apply Epoxy, then high build. Note your "windows" and "flash" times for your products. Block high build around 320-400 grit, finishing over the 320 with around 500-600 grit using an inerface pad with the 500-600. If it does not block the first time, you can re-glaze, re-apply high build and try again. Apply sealer, then two color coats, two clear coats (for non-tricoat, bc/cc systems). Also note, that regular wax and grease remover can not be used on plastic, only wax and grease remover specifically labeled for plastic use can be used.

Long winded.

 

hey thanks for the detailed response.... I was using 320 grit the p/o had spray painted black over the gold bumper it came off easy but we did take it right down to the urethane. We didn't go to deep into it tho just lightly. Your instructions will be a good guide for me and my brother.