took my plastics off last night and was wondering how much I need to sand. Do I need to go down to bare plastic or just enough to knock the shine off?

 

That depends on how well the existing paint sticks and how many layers there are. Also, make sure it wasn't can painted previously (enamel). If so, you have to get rid of all of that (unless you're can painting again). Make sure you feather out any chips/deep scratches. I'd recommend starting with 220 grit and moving on to 400 after a couple good primer coats (more if it's needed to fill very small imperfections) The best way to go is all the way down to the plastic, but it's very time consuming, unless you know somebody who can media blast plastic (check around, this could save you alot of hassle). If you can get all of the paint off, make sure you 400 grit the bare plastic and use an adhesion promoter (bulldog is best) right before (and I mean right before you paint). What kind of paint are you planning on using? Some say that a single stage urethane is best for flexibility, but a base/clear urethane will work perfectly.

 

Yup, its a urethane. I told the guy at NAPA I wanted something easy and that is what he gave me. The plastics have factory paint on them so I was thinking all I would have to do is sand it to a dull surface without going to bare plastic. Bare plastic vs. dull surface ... I have been told either will work fine , but I am counting on the dull surface to work because all I have laying around is 800 grit and its a b$tch getting down to bare plastic and all the shops are closed now so I cant get any paper.btw paint is a graphite metalic pearl from the lexus/toyota line.

 

800should work, it'll just take a little longer. A regular 3m scotch brite pad seems to work great for me, if all I need to do is knock the shine off. Good luck man, sounds like a sweet color.

 

thanks, I'll post pictures when I'm done

 

You're gonna put down a urethane primer first, right?

 

The guy told me I would be fine with just sanded plastics. If I'm only dulling the surface do I need to prime?

 

You really should... and the more I think of it, the more I would really like you to get some 400 grit. I'm not sure that 800 will give a rough enough surface for the paint to hold on to. By all means, get a second opinion from a pro. I just do this in my spare time.

 

Problem is, they are a few different schools of thought about bodywork and painting, so don't be surprised if you hear a diferent answer from everybody. They best way to learn this stuff is from experience.

 

I know a guy who painted his truck on top of a sanding with 180 grit! It turned out great!! He is just amagicianwith the paint gun, i guess...