SEM self etching primer on top of color/clear/underseal?

[Benson]

Etched it up, wooooooooooot!

[Len]

If I were using those materials and wasn't real concerned what the end result looked like I'd prep and mask then spray my primer and paint materials out of the Preval. If you want it to look good the procedure will get more involved. Personally I'd opt for flat black to make the repair more unnoticeable.

[Benson]

Hi Len,

thanks for your prompt reply.

I'm not too concerned about what it looks like as it is the bottomside of the fender lip.

I just want to do it once and do it right without the paint lifting or anything of that nature.

Will the high build primer by itself suffice for this job or do i need to use self etch? But I'm worried that the self etch primer will damage the existing underseal and/or clear and color.

Benson

[Benson]

I'm thinking I can omit the etch primer since there is no rust whatsoever. What do you think?

[Steve g]

The acid in the etch is not so much about rust, it's about adhesion. Bare metal needs either etch or epoxy for proper adhesion. The etch won't be a problem over the previous finish, but if done right most gets sanded off anyways. The idea is that you cover the bare metal with the etch. Your primer surfacer builds the area back up to the level of the existing paint around the repair area. When you sand it you level out the repair with the surrounding area. In the process of doing this you are sanding off the etch and primer that accumulated beyond the repair on the existing finish.

Steve g

[Benson]

Thanks Steve. Will report back shortly.

[CrimsonCustoms]

if ur bout to paint and have bare metal or bare bondo, I spray decent coat of the sem spray can primer over those areas. This works great and stops the base from sinkin into the bondo.