re-painting black undersides

[CorvallisBMW]

I want to re-paint the black parts of the body below the doors, bumpers, etc. Mine is looking really crappy. What kind of primer/paint should I use? I know it sees a lot of abuse, so I was thinking about some of that flexible undercoating stuff but I don't know what the finish is like. Anyone have some recommendations? self-etching, regular, sanding, rubberized, etc......

[JGood]

I want to re-paint the black parts of the body below the doors, bumpers, etc. Mine is looking really crappy. What kind of primer/paint should I use? I know it sees a lot of abuse, so I was thinking about some of that flexible undercoating stuff but I don't know what the finish is like. Anyone have some recommendations? self-etching, regular, sanding, rubberized, etc......

I just use Duplicolor trim paint and do it once a year or so. No matter what paint what you use it will get bitched up, but it only takes like 1/2 an hour to do a decent prep/tape job. I'm talking about the rocker panels here... not sure what other parts you are referring too. And I wouldn't recommend this on a show car, does just fine for a daily driver though.

[CorvallisBMW]

Yup I meant the rocker panels, i just couldn't find the right words for em.

[Jordan]

I washed my car paying extra attention down there, dried it, masked off the line, and then hit it with SEM trim black, same paint used for shadowline.

Looks OEM, and has not a single chip as of yet.

No sanding, no self etch primer, just shoot it with SEM.

[KenC]

On my 84, I cleaned all of the road grime off with goof-off, and then shot it with duplicolor rubberized undercoating spray. It took several hours to dry, but I thought it looked pretty good.

[Jordan]

oh and FYI.. the SEM will be dry enough to drive in the rain in 10 minutes.

[Van Westervelt]

SEM and Duplicolors Trim Paint are pretty much chemically identical. Duplicolor is just more readily available.

[nando]

dupilicolor trim black is pretty decent. I can get SEM just down the road but it's a lot more expensive..

[smonkbmw]

i did the duplicolor undercoating. held up a piece of cardboard to "mask" it off and just ran over all the trim with it.

[Jordan]

My condolences.

[jw 325ic]

i did the duplicolor undercoating. held up a piece of cardboard to "mask" it off and just ran over all the trim with it.

My condolences.

hahaha i wonder what kind of overspray you got.

[Sponce]

haha, im lame, i used rustolem, semi gloss black, took no time, still looks great, 1 month later.

[dinanm3atl]

I washed my car paying extra attention down there, dried it, masked off the line, and then hit it with SEM trim black, same paint used for shadowline.

Looks OEM, and has not a single chip as of yet.

No sanding, no self etch primer, just shoot it with SEM.

This is the only stuff I have heard to use. I am going to use it also :)

Worked great on the spoiler 8 months later!!!

[smonkbmw]

got zero overspray. just takes some talent.

[xLibelle]

SEM Chip Guard is THE thing to use for this! no primer, nothing else