Not sure if this is the correct forum to post this question in but what the hell.
I told my buddy I would touch up some nicks in his 98 caddy catera. Unpon further inspection I found a pretty good sized rust spot at the rear wheel well. I was wondering if anyone could recommend a good product as a pre-treatment before I apply the touch up paint. Thanks.
Matt

 

Nothing ... if there is rust is needs to be totaly removed, which could be either sanding the area down or if its through the metal replacing the pannel or rested area. You don't want to just paint over rust ... unless to get rid of it totaly it will come back and ruin the area you just painted.

 

True, very true. I guess I didn't fully explain myself. I have these cool bits with sand paper on them. they are all different grits and shapes. I am going to go in there and just get rid of as much as I can. Then I was thinking I would treat the edges and touch up slightly. It is not directly visible, its right on the underside of where the metal folds into the wheel well. Astetics aside, what can I pre-treat the area with before touching up, or is it not even needed?