Need a paint guy to set me straight

I just put some PPG two part primer on the Buick. I have some salt flat like cracks in it. I had wiped the car down with lacquer thinner, was that a no no ? If not that, what?

 

never pre clean with lacquer thinner. what did u primer over? lacquer? give a run down of the steps u used.

 

The car, a 64 had been repainted some time ago with what I don't know. I used a little bondo like filler and some glaze. Put rustoleum primer where I had worked on it first. The cracks are random, some , but not all where I worked on the body.

 

is it a catylized primer?

 

I believe the rustoleum primer is your problem. The PPG primer attacked the underlying rustoleum

 

what did you sand it with before you primed it?

 

I believe the "salt flat cracks" you are referring to is called "lifting" in the paint world. Proper procedure for that would be to sand to the base of the lift, in this case back to bare metal. If it is just in one spot, then follow procedure for spot repair. If it is the entire car, take it all to bare metal, hit it with 180 (some use 80 grit), use some wax and grease remover to remove any dust, wax and debris, then use a tack cloth and spray your primer (self etching primer preferred).

I may be wrong...pictures would help.

 

Maybe the cracks were already there. Lippy

 

I just read post #3. Could it be as Lippy said and the cracks were there already? Like when old laquer paint starts to give up the ghost?

 

Rustoleum is enamel based and the catalized stuff will eat into it. My guess.
Needs to go to bare metal.

 

The reason I said that is, you know how 2k catalyzed primer wont go into a pin hole? You can rub your finger over it while it's wet and it will. When you put catalyzed primer over a cracked surface it will do the same thing. It seems to be drawn away from the crack. Just guessing.I agree it needs stripped. Lippy

 

yep thats your problem. Rustoleum is a no no in the paint world.

 

No cracks were on it, I had washed the car with Dawn, sanded with 220 and washed again. The primer is "Shopline" JP202 with a reducer and a hardener' I got it from a PPG dealer here. I just sanded a couple of the 1/2 dozen places off, dosen't seem to be a common denominator. It did it over the paint, the filler and the Rusto, then again it didn't do it over all the same stuff.

More answers while I was slow typing, I can sand down to metal if needed, it's not the whole car. But it will be a pain. How bout just the places it cracked?

 

Did you use wax and grease remover before you sanded it in the beginning? Lippy

 

Just the Dawn, I was typing when you were posting.

 

We will call you strip from now on instead of Skip. lol. Got any pics of this deal? Lippy

 

Try and repair one spot and see if it happens again. If it doesn't "crack" again you should be good to repair the others. Just remember to not spray too "wet". That could also be a problem.

 

Just a fine pencil like line, they won't show up. And I'm calling myself a couple new ones right now. And I can't wait until the"why not hire someone to paint it" wife gets home!!

 

Don't tell her!! Simply say, yep it's looking good hun!, no problems here, see ya later for supper.

 

well if it did it on the old paint, i assume it's not to the bare metal unless the cracks were already there, and you say they were'nt, so i think you either put the first coat of primer on way to heavy, or you didn't wipe it off good and you left some kind of film on it that contaminated it and made it seperate. wet sand the affected area's and reprime it by dusting a tack coat first and then 2 wet coats after that. if it don't crack, wet sand it again w/320 and try not to sand thru it and put 2 more coats on it. if it cracks again, you'be taking it to bare metal. good luck.

 

First I pitch the Rusto, I'll let it dry overnight and try that. What can I wipe it down with?

 

Hey Skip,

Don't kick yourself over what you may or may not have done when it comes to paint work, there are plenty of people willing to do that job for you!

Ya learned somethin' that won't work and atleast this wasn't the top coat and ya had a couple grand tied up in paint materials. Sometimes ya can do everything to spec. and still have everything turn to shit, it happens!

" Spending a nation into generational debt is not an act of compassion "

 

Rustoleum will do that if you don't give it enough time to dry. It needs lots of time. Several days or even a week, depending on the weather. Once it's cured you should be ok. A lot depends on how heavy the Rusto was applied.

 

The Rustoleum is most likely the problem. I would take down any area that you applied the Rusto at least to the old paint, if not bare. Then try the primer again.

 

When I run into a lifting problem, I sand the lines away and apply a water based primer. As long as you dont break through the
water primer layer, you are good from there.

 

Look on the bright side. You just got your wifes blessing to have a pro paint it!
Take it in, get it painted, hand her the bill & tell her you love her for being so understanding!

 

+1 to the rusto being the problem, sand the "cracked" areas down till they are smooth, to bare metal if needed, put a few dry coats of primer over to seal the area, sand the car, careful not to break through the surface and re-shoot the whole shebang, a few dry coats. wet coats will bite into the rusto. Take your time

 

Thanks for all the help, I'll check back tonite with the results.

 

Don't feel too badly. I've painted bunches and a couple of weeks ago, I was getting ready to paint two bass guitar bodies. The plan was to epoxy prime, 2k, smooth and paint.

Snatched up my gallon of epoxy, added the hardener, let it set the 15 mins required, dumped it in the gun and sprayed the bodies. I thought it looked a little dark and man, it sprayed thick and was difficult. Got it done though.

Went back to dig up the 2k and noticed the epoxy in the rack. Hmmmm...why is the epoxy here, what's on the mix table....

Sealer. I sprayed sealer with hardener. Well...dumb mistake, let's go ahead and do what I wanted. Sprayed epoxy over the sealer. 2k over the epoxy and they sprayed well and it looked great.

Came in the next day to start sanding....huge 1/8" wide cracks all over both bodies.

Restripped them both. Glad it was only bass bodies and not a car. Sometimes I amaze myself by my idiocy.

 

Ditto what the others have said about the Rustoeum.

& you want to stay away from the Dawn as well, that stuff is mostly salt....