Is it normal to have very fine lines or cracks in primer?

[Chlngrcrzy]

Been working on the primer on my front quarters, and no matter how many times i shoot (PPG NCP), it seems to have some very fine cracks in it. I have sanded this stuff down untill their gone and it almost takes it to the metal. I have tried slower reducers, that doesn't seem to matter either. Maybe this is normal, don't know. I have my fenders smooth as glass from apperance and touch, but i don't know about this crack thing. After i spray the sealer shot, it is not noticeable, but i haven't been entirely satisfied with the sealer, so i have wet sanded with 600, and that is when i notice the primer cracks. Do i need to keep working on getting my sealer perfect or should i just move on to the base?

[QuartermileCuda]

I did my cuda all will PPG products. Even the NCP 270. I love the stuff. I had never run into that kind of problem where it would crack. I have used that primer for fixing cars in our body shop for the past two years. How old is the primer and hardeners you are using?

[torredcuda]

Are you spraying on bare metal or over old paint?If the old paint is cracked the primer may also look cracked.

[dutch]

never heard of that before.  did you keep the primer above freezing...?   

[farmboy70]

Could you post some pictures? I would guess it is shaddowing something under your primer but if it has been stripped that is out. What is under your NCP?
Dave

[Chlngrcrzy]

Ill do my best to get a good shot. not sure if my camera will go down that close.  It was all bare metal treated with PPG epoxy primer. Not sure i descibed my problem very good when i called it fine cracks. Let me descibe it again.
I have applied about 6 shots or so of primer. After the first 2 or 3 i threw on a guide coat and began sanding with 180. Once that was done i applied 2 more shots of primer, threw on a guide coat and sanded with 180, and then with 320. That looked pretty straight after that. I applied again and then began to wet sand with 600. everything lays straight and feels as close to perfect as i thought i could get it. However after washing all the materials off, i noticed that i had very small freckles, cracks or whatever you might call it in certain areas, nothing specific to the metal, more like i didn't sand down far enough. However if i began to work it down further to get rid of the freckles, etc. i start to break through to the metal in places. So what am i doing wrong. I have applied so much primer on just my front quarters and hood (1/2 gal) i am going broke trying to get it perfect. When i did the work on the car earleir it never showed up like this. whats my chances that the base will be fine? This is not a show car and never will be, but i want it to be as right as i can make it.

[QuartermileCuda]

How clean was the metal when you first stated laying primer down? Did you use any cleaners?

[Chlngrcrzy]

Clean, clean and cleaned. Call me a bit paranoid, but i have read about too many incidents where something created havoc on a paint job.

[OUTLAW]

you are shooting it too wet. also are you using reducer or laquer thinner? for the temperature you are shooting in, the surface is flashing then as it cures deeper you get cracks-also if you reduced it in the wrong ratio it will crack too

[Chlngrcrzy]

you are shooting it too wet. also are you using reducer or laquer thinner? for the temperature you are shooting in, the surface is flashing then as it cures deeper you get cracks-also if you reduced it in the wrong ratio it will crack too

Using Reducer. Tried 870 and then 885, with a heated garage. I will try a drier shot, not so wet this next time. Thanks