What is primer?

[maxpower]

I have a quart of Auto Air sealer. Is this good enough as a base coat to use instead of primer or do you still need a primer (the stuff in the cans you get from the store) as the first coat?

I thought I asked this before but couldn't remember and didn't see it on the forum.

Thanks

 

[RimfireJim]

In the PPG auto paint products I've used, a sealer is a non-build product intended to seal between different products to prevent compatibility problems (such as new paint over OEM), whereas a primer has solids that build and fill and can be sanded out to get a smooth surface as prep for the finish coats. And then there are primer-sealers, high-solid primers, etc., etc., that all get very confusing if you try to learn just by reading the data sheets. I just asked the guy at the paint store what I needed

 

[Stymye]

the AA sealer is a low build( and non sandable) coating that can be used over a prepped surface, just before painting the actual colors, they have a white sealer and a black sealer.

it's not for filling imperfections or anything like that ,, look at it as simply a basecoat between the primer and first color

basically what Jim said

 

[maxpower]

OK. That makes sense. AA has a primer but it says it is for metal surfaces so I thought maybe the sealer was for wood. However, since it is low/non build and not sandable it is not going to work. I will stick with the smelly rattle cans.

Thanks