metal sanding

[grim0404]

i have a 1967 mustang i started to sand down the mustang to bare metal i got 90% done then i cleaned it with a degreser then primered it very heavy amonth later it started to rust what do i need todo??or what is the process to paintin from bare metal and where can i find it??

[Geeko]

Did you use any cleaner or sanding between the degreaser and the primer? also, how many layers of primer did you put on, and how thick were they? in general, you want thin layers of paint, with some sanding in between to help it stick.

I could be wrong, though, I havn't painted many entire cars.

[grim0404]

after degresing it i didnt sand it i cleaned the degreser with a dry rag then i proceeded to primer then a month later im getting rust i regret sanding it

[jveik]

yeah you maybe had a film of crap on there from when u degreased it that wouldnt allow the primer to stick very well. also, ive heard from some people that primer lets water through it so if it was wet a long time maybe it let water in because it didnt have normal paint on top to keep the water out.

[astroracer]

What kind of primer was it? Probably a SS primer/surfacer. It will let moisture through and the steel underneath will rust. You'll have to sand it all off to make sure all of the rust is gone. Next time shoot it with a 2 part Epoxy primer to seal it then spray the primer/surfacer over that to finish your body work and blocking...
Mark