Primer Question (1 Viewer)

[Vincenzo]

I am on the ever so slow resto of my 72 40. I have been wire wheeling/sanding body panels to bare metal and then using a basic rustoleum grey primer to protect them as I move on to the next panels.

When it comes down to the epoxy primer stage, can I just spray it over the rustoleum, or will I have to remove it first?

Thanks for any input

 

[Krondor]

I would recommend removing it first. Paint is only as good as the surface below it. You really want clean metal for the epoxy primer to bond with. Also some 2k primers and products can react badly with single stage rattle can primers.

 

[Vincenzo]

Thank you, looks like i'll be doing some double work

 

[macdaddy59]

Yep return to bare metal than epoxy prime to insure good adhesion and rust prevention.

 

[DougAustinTx]

If you want really good paint adhesion to the epoxy primer, scuff it with 500 wet/dry (add a few drops of Dawn dishwashing soap to the bucket you are using to wet the sandpaper you are scuffing the primer with, and you are less likely to get fisheyes in your final paint)

 

[DangerNoodle]

If you want really good paint adhesion to the epoxy primer, scuff it with 500 wet/dry (add a few drops of Dawn dishwashing soap to the bucket you are using to wet the sandpaper you are scuffing the primer with, and you are less likely to get fisheyes in your final paint)

I'd not use any soap or water. I would use a wax and grease remover specifically designed for use in paint, and dry sand. Mechanical adhesion is the best, so scuffing the paint is the best way to go. Good prep, good paint.

 

[Vincenzo]

Thanks for the input. I'd hate to leave body pieces sitting around bare metal as this process is going slow for me and may take some time when I actually will primer the whole thing. Any suggestions on leaving bare metal panel inside the garage? coatings? I am in Phoenix, so I'm not worried about humidity?

 

[DangerNoodle]

Thanks for the input. I'd hate to leave body pieces sitting around bare metal as this process is going slow for me and may take some time when I actually will primer the whole thing. Any suggestions on leaving bare metal panel inside the garage? coatings? I am in Phoenix, so I'm not worried about humidity?

Get a good epoxy coat down and stop worrying. That is what I have been doing. As long as they stay inside after being coated you should have no problems at all.

 

[macdaddy59]

Yep bite the bullet and put some epoxy paint on them. That reduces the rework of sanding and painting.

 

[rainingagain]

A wipe down with wax and grease remover, then a tack cloth should be the last step right before painting. Definitely do not skip on that or you will have fish eyes.

It's best to leave the primer / old paint on until you are ready to actually paint. Like you said, you don't want bare metal pieces laying around for long. Do you know what kind of primer was layed down? Like was it actually rustolem? Some high quality rattle can primers are fine to paint over as long as you are not looking for a show quality job. You will for sure want to scuff up the surface first. No need to wet sand until you are on the final coats of primer.

 

[Vincenzo]

A wipe down with wax and grease remover, then a tack cloth should be the last step right before painting. Definitely do not skip on that or you will have fish eyes.

It's best to leave the primer / old paint on until you are ready to actually paint. Like you said, you don't want bare metal pieces laying around for long. Do you know what kind of primer was layed down? Like was it actually rustolem? Some high quality rattle can primers are fine to paint over as long as you are not looking for a show quality job. You will for sure want to scuff up the surface first. No need to wet sand until you are on the final coats of primer.

It was rustoleum auto primer grey, I had to get something on it while the vehicle was transferred from Houston to Phoenix. I am unable to put down any epoxy primer as I haven't repurchased a compressor yet, and with what's going on with resurgence of COVID, expenses are limited.