paint stains

[MikeAtkinson91]

Hi guys, I'm new to the forum here and I have a problem.which I would like some information about

I have been asked by a work colleague to have a look at a particular stain he has on a car which he has just bought 2nd hand, its an ex-police car so at first glance I thought it was an adhesive stain from the decals which would come right off with some tar remover, unfortunately this did not seem to work, i then tried some clay on it, still no joy, i then went all out and tried to buff it out with some M83 and a microfibre pad, still, no joy!
The stain lessened as i worked the buffer for longer but it's no where near gone

The only other step after that would be for me to wet sand around the area, however,not knowing much about the history of the paint I chose not to follow sanding up and called it a day for now

It is a yellow stain, The surface feels smooth with no noticeable edge on the stain so it can't be above surface, i think it may well have stained deep into the clear coat coat, what do you guys think?

Now to end it on a bit of a laugh - the guy my work cocolleague bought it off said 'the paint had faded in the sun' I believe that may be a load of BS, but what do you guys thinK? Also, the filler cap seems to have been brush painted with some white gloss :lol:

Thank you for your time :)

http://i149.photobucket.com/albums/s52/atkinson_91/Mobile%20Uploads/Screenshot_2015-02-19-20-19-39.png (http://s149.photobucket.com/user/atkinson_91/media/Mobile%20Uploads/Screenshot_2015-02-19-20-19-39.png.html)http://i149.photobucket.com/albums/s52/atkinson_91/Mobile%20Uploads/DSC_0077.jpg (http://s149.photobucket.com/user/atkinson_91/media/Mobile%20Uploads/DSC_0077.jpg.html)

[Setec Astronomy]

That looks like the remnants of some police marking paint that hand painted on top of the factory paint. I once made the mistake of convincing my friend that we could sand the painted stripes off the front doors of the ex-cop car he was buying. He wound up having to get the car painted.

I'm sure you'll get some better opinions, but you could try to carefully wetsand, as you suggested, or get something more aggressive than M83 (M100, M101, M105, FG 400, Wolfgang Uber, Optimum Compound, etc.) on a MF pad as you alluded to. Just be careful not to remove too much material from where the yellow isn't.

There is no evidence of similar marking on the other side of the car?

[Mike Phillips]

Defects in paint are either "on" the surface that's called topical defects. Or they are "in" the paint, these would be called below surface defects.

Topical defects are pretty easy to remove, simply use a compound, polish, paint cleaner or AIO by hand or machine to remove.

Below surface defects, if they are not too deep can also be removed by hand or machine. In most cases you'll need a compound to remove these types of defects.


Troubleshooting
Here's how you test. Simply place a tape-line of painter's tape over a section of the stain and then rub or buff on one side of the tape line. After a few about a minute, wipe off the residue and compare the side you worked on with the side that you left alone.

Your eyes should be able to tell you if you're making any progress or not. If you see progress, even just a little that's a good sign. It means with more rubbing or buffing you should be able to remove the stain.

:)

[Mike Phillips]

The pattern of stain around the gas cap looks like this was in fact caused by some type of graphic and the circular pattern is just to exact.

If it were me... I'd either get a quality compound like the Pinnacle Advanced Compound (http://www.autogeek.net/pinnacle-advanced-compound.html) and a microfiber applicator pad and rub hard and fast to a small area at a time or whip out my trusty, dusty Flex PE14 with a wool pad and the same compound and have a go at it.

Let us know what you find out...


:)