Need a painters advice..

[Sparky73]

I'm getting ready to spray my tailgate, and ran into a little problem I cannot figure out. After I finished with the body filler, I coated with a standard light grey High-build primer and sanded smooth. I figured the color might be a little too light considering it's going to be painted black, so I picked up some black sandable primer and re-coated with that. It layed down really well, so after a few hours I went on to wet sanding that as well. Got ready to spray the paint, and started wiping down with PPG Wax & Grease remover...

BAD IDEA. The wax and grease remover basically took off the top layer of black primer like I was using paint thinner. Now, to my question.. do you think the primer or the grease remover was the cause? I always used this before between each coat and never had any problems!

Another question.. could I just spray the black paint over the light grey filler primer, or would I have to put a bunch of coats down to make it look decent?

[heimue]

It's very strange that a de-greaser wipes away any kind of paint or primer. Are you sure it is de-greaser, is it possible somebody filled in laquer thinner and the primer was synthetic resin based? Anything else is unthinkable to me.
You can paint black over any base color, or to say it in basic words: You can always overspray with a color that is about the same "darkness" or darker than the original coat. You have to spray two layers anyway.

Dieter

[Sparky73]

Exactly my thoughts. No, it was not mixed with laquer thinner or anything like it. I keep ALL my paints, cleaners and chemicals on top of my toolbox, and am also the only one that uses them. Hell, I'm usually the only one in the garage lol.

The bottle of de-greaser I used has been used on other projects as well. There must have been some sort of chemical reaction as the grey primer underneath was unharmed.

So I should be okay to just sand everything smooth again, and paint with the grey primer showing through the black primer?

[Mike Trout]

The wax and grease remover didnt cause it, it was the primer, there was a chemical reaction between 2 components that did go good together get yourself some DPLF Epoxy primer, you can put it right over bare metal and filler and sand it, and you can get it in grayish black color so you can achieve great color hiding, the stuff is fantastic we use it on all our restorations, clean with wax and grease remover and spray 2 coats of the epoxy and lightly sand or scuff any dirt out in between the 1 and 2 coat, then scuff lightly the second then put your base down
Mike,

[blancojp]

The primer you had should work just fine with a black color coat.

The problem there was the bottom primer had cured but the top black primer had not. I ran into a similar problem some time ago by trying to go from primer to base coat within a few hours. Other than the Gargoyles making fun of me the remainder of the day, the part was re-sprayed, cured in the bay and then sprayed OK.

[Tru-Craft]

I agree with JB.
One thing nice about having light primer base and then a dark primer over it, is it shows low spots when final sanding.
Using a long block sander or a paint stick works great.
Lyle

[ungermm]

Just wondering if you were using Dupli-Color Sandable Primer. I have used this rattle can for spot treatments before and haven't had any real problems. However, I do think it is important to let it cure for a couple hours at least. If it is humid or cool, it's better to give it extra time. I did have a problem with this primer wrinkling on a set of wheel center caps after months of cure time and then laying down a very thick color coat over it.
I just went out a tried wiping a spot that was sprayed with the above gray hot rod primer over a couple weeks ago. I used a pre-paint cleaner/de-greaser. Guess what?, even though it didn't all come off, I could see that the cloth that I used with the cleaner/de-greaser had taken off some of the primer.
Jerry

[Sparky73]

Thanks everyone. I will probably just sand it smooth again, and not worry about the grey primer. If it takes more coats.. I'll add them! lol.

Mike, I do believe you are right about the chemical reaction as well. But isn't Epoxy primer used for bare metal? I sprayed the epoxy primer before applying the body filler. Then you spray high-build primer, then then sealer, correct?

Humidity was quite high, as it always is, so I'm sure that didn't help with the curing. Temperature was around 75 or 80.

I'll stick with the original primer I've used for years (the grey High Build) and forget about trying to make the primer a different color. I'll post pictures of how it comes out.

Thanks again!