Thread: how to repaint bumper?

moved to not the how-to section.

Visual/Body Modifications At Your grandprixforums.net
there you go

I've got plenty of experience to go around, but first things first;
1. You want to sand the bumper.
2. You then need a proper prime. Sand your bumper all the way down with a 600 grit sand paper until it turns black. Then clean it with denatured alcohol or your basic paint thinner. The reason why I used denatured is because it's potent and a better cleaner, but paint thinner is cheap and effective. Then you need to sand down to make it fine with an 800 grit. or better known as "wet/dry" sand paper. If you were sanding to metal you can use the wet sand technique, but this is not exactly what you are looking for.
3. Now you have to tape everything off, and I mean everything. All the seams, and even down the sides due to over spray.
4. You want a good prime coat. You have your "can" measurements wrong unfortunately. If you are going to rattle can it, 3 cans of primer will do the trick, and that's way overdoing it since it's only a spoiler.
To the basics; you want to get a nice coat going, so you'll need it to be suspended in a dust free room. Suspend it by the two screw holes. If you can't suspend it place it on an area that can have low visibility that can be somewhat messed up, but I don't advise it.
A. Apply you first coat. Be very careful when applying your first coat because this is the one that is your foundation. Wait 30 minutes - 1 hour and sand with a 1600 grit to get a good clean foundation. Repeat 3 coats and it should be good.
B. Next would be bottom coat or "Color". There are some automotive paint shops that can sell you hardener and paint mixed into the cans. I would suggest going this route since it will save you a lot of time with your seal coat and Gel Coat. If you go this way you will be using the method I explained above. NOTE: be warned if you don't let the hardener set up in a hot room or overnight, you will FUBAR your whole project~! If you are using the method I'm about to mention it will provide you with a cleaner look in the end, but it will cost you valuable time which is worth it.
C. Use the method I described above with sanding, you MUST use a different sheet of sandpaper for each coat! Some people disregard this and eff it up. When you have applied your 3 coats let it set up overnight. Now on to the hardener
D. When working with the hardener, it's the thing that makes it shiny. I advise you not to use and sandpaper between coats because it will cause "wrinkles" or "divots" in your shine. This is what will be making the time go very slowly for you. Top coat set up times are 3 hrs for excellent results. 4 coats will perfect it. So do 2coats per day and you'll be golden. Some others that paint may look at this like a little amateur, but use your best judgement as this is the best way I could break it down to you in my own words. Hope that helps!