Morning guys,

I did some specific searches but did not find a thread asking about the black primer that comes on some of the body panels. I removed it everywhere I had to weld. Do you guys remove all the black primer or leave it? Does anyone know what kind of primer it is? I read somewhere it was epoxy but find that hard to believe.

 

Wipe it with reducer, if it comes off it is just cheap black primer to prevent rust. If it stays on it should be good to scuff and shoot.

 

I have never found the primer supplied on new pieces of very good quality . I would remove it then you know your base is the same everywhere . Just my 2c .

 

There are fairly decent e-coatings on quality panels and there are any number of spray coatings that "look" like e-coat but are only good for keeping flash rust off the panel. As a rule of thumb, I sand the black coating down to the metal in one area of the panel...if the coating feathers out then the adhesion is good. If the coating goes from black to silver immediately then the coating is flaking and should be removed.

 

The new front panel for my truck bed came with good primer on it.
Truck bed front panel

It looked like black ecoat powder was used but not sure as acetone did not touch it and it was flawless. I did rough up the surface with 400 grit before painting it.