When should I "sand" using sand paper before I paint?
There is a black strip of metal between my driver’s side window and the car door. The black strip of metal had been losing its paint such that you can see the silver metal underneath. Today I sprayed flat black paint onto the black strip of metal and the paint did not adhere to the black metal strip (you could still see the silver metal).
Given this, I had read that sometimes “sanding” with sand paper and then spraying the metal strip would help the black paint adhere to the metal strip. Is this true? If not, what should I do so that the black paint would adhere to the metal bar?
Observing members:
0
Composing members:
0
4 Answers
You need to scuff it up so paint will adhere, sandpaper works great for that
Welcome to Fluther.
It sounds to me more like the paint was too thin, or perhaps too thinly applied. That is, if you can “see through” the paint… but it’s still there. So while @ARE_you_kidding_me‘s advice is good in any case: the metal surface has to permit the paint to adhere in the first place, the paint also has to be a type that is suitable for the purpose. Some spray paints adhere to some metal surfaces better than others.
Since you’re talking about a “silver” metal (in an automotive trim application) it sounds like a chrome (chrome-plated) surface to begin with, and I’m wondering why it was painted in the first place. Still, if the surface is slightly scarified to permit adhesion of the paint, that’s a good start. But if the paint isn’t actually flaking or peeling off from your first application, then just let it dry suitably, and apply more on top of what you’ve already got.
Mask off the areas that you do not want to sand. Remove all loose paint, then sand the metal with fine (at least 200 grit or finer, like 400 grit sand paper), wash area sanded with soap and water, then wipe areas you sand with lacquer thinner on a clean, lint free rag. Then apply your paint. If you apply primer before the paint, you will have to lightly sand the primer, too.
What kind of paint are you using?
Answer this question 
This question is in the General Section. Responses must be helpful and on-topic.
Composing members:
0
