Totally confused about primer!

[mjr45]

OK, after reading numerous posts both here and on various auto paint sites, I'm totally confused about primer. My 75 has several small areas and 1 larger area (8 sq. in.) of body filler and glazing, multiple small areas sanded down to bare metal. What primer do I use? I've read "primer 1st with epoxy then high build and another coat of epoxy after sanding." "Primer with high build, sand down then seal with epoxy." "Spray bare metal with self etching, then high build, sand then epoxy prime." So I am totally lost. The entire car has not been taken to bare metal, but sanded up to 320 grit. Help, whats next?

[ncolz]

OK, I'll take a shot here and suggest what I would do with your car...... First - it would be ideal to take the whole car down to metal and go from there. Sounds like you don't want to do that, I understand. So, the 'next best' from my perspective, is to take out as much filler as possible, then prime all the bare metal with etching primer. Add the fill back in to smooth, then to the high build and work that to get it straight to your satisfaction.

I like to know all the body work done on my projects. If the filler was from someone else, I prefer to take it out and see what I have underneath. Yeah, I know that's like opening up Pandora's Box at times - but at least I know what I'm working with then. I also know that all the materials I use are compatible. It really sucks to do nice body work only to have the paint bubble due to some reaction with incompatible stages.

There you have it.... advice guaranteed to be worth what you paid for it.

[mjr45]

You're right I don't want to take the entire car down to bare metal, not enough time before it has to be back on the road as it will soon be my primary ride.The areas that were filled were sanded down to metal before and after filling and are just bare right now as are all the small areas, no primer or paint. The rest of the car is sanded down. I'm trying to figure out what primer to spray first self etch, epoxy, high build? The car only had one cancer spot on the body that I cut out and repaired, the underside was a different story!

Edited June 24, 2011 by mjr45
added info

[ncolz]

Most self-etch primers I've seen suggest not to spray on fill - so you can mask those areas off and hit the bare metal with the etch. Let that dry, then hit it with the high build -- work that down to what you want, then either epoxy or just paint on top of it. Make sue you use compatible products (notice a theme here? ) I just buy all my products from the same supplier and let them know what I'm doing. Sure makes that part of the job much easier.

[steve91tt]

Not all self etching primers are the same. The cheap ones are single pack alkyds. These are great for getting adhesion on bare metal that cannot be perfectly cleaned. However, if it were me and I had to choose between a 2 pack epoxy and a 1 pack self etching primer on clean body panels I would go with the epoxy. I don't see the advantage of the extra adhesion provided by the self etching feature on clean, sanded steel. When you take adhesion out of it, the epoxy will give better corrosion protetion than the alkyd binder used in many self etching systems. In the end it's going to be up to you. Both will likely protect well enough for a car that won't be used much in a corrosive environment. However, if you were planning to drive it on salted roads then I'd definately go with the long term protection afforded by the epoxy.

Just my $0.02

[ZCurves]

..."Spray bare metal with self etching, then high build, sand then epoxy prime."

Once the body is nice and straight, spray EVERY surface with Self Etching, then High Build, finally seal with Epoxy Primer. The key is to be consistant and UNIFORM. Obviously the Self Etch will only react with the bare metal -but it will seal the rest of the surface at the same time and provide an uniform surface for the High Build. Make sure to use products from the same manufacturer. It is NOT a good idea to mix and match as these "Paint Systems" are designed to be compatible and provide consistant quality results. You can see the various stages that my Z went through by looking in my Gallery (Albumz) below.

Edited June 24, 2011 by ZCurves

[Patcon]

Everything I have read says epoxy first, body work then epoxy again or sealer coat. You could spent some time on the paintuction forum or the eastwood forum if you wanted to get some more opinions. There tend to be a good number of full time painters on those forums...

Charles