Need some opinions on the PPG shop line JP epoxy primer I've sprayed on my car It was my understanding that epoxy primers once cured would not be affected by lacquer thinner In cleaning some overspray off the epoxy I sprayed I noticed primer coming off on the rag I used The local PPG rep tells me this should not happen , I tried every panel I have sprayed . Doors and deck were sprayed at a different time with a different quart and they do this as well I even tried the rear end I sprayed with Napa Martin Senour and it does this as well Thoughts ? Thanks Mike Posted using the Full Custom H.A.M.B. App!
I'm no expert but lacquer thinner near any green paint ,paint it gonna lose. Just my two cents worth.yruhot.Doug
can the PPG rep come look? he can sort it out, other than that, perhaps not cured enough? correct hardner and amount?
Thanks The counter guy stated that he thought it was no cured either. I sprayed his last fall, can't believe I mixed it wrong on multiple occasions Also given the time that has passed I would have thought this would have cured regardless by now The other thing that concerns me is the rear end will do the same Posted using the Full Custom H.A.M.B. App!
Is it lifting (crazing) or just coloring the rag? Is it sanded? Can you simply wash it off with lacquer thinner? Of all the common solvents we use in this car stuff lacquer thinner is the most aggressive to refinish materials of any type. If it's not wrinkling then it's fine. All primers, epoxy, urethane, old school lacquer primers, even self etch, they're "cellular" in nature. That nature allows a primer to hold a finish both chemically and mechanically. FWIW, color grade lacquer thinner is the most aggressive, and most all of them will even remove semi-gloss and flat powdercoats if scrubbed hard enough.
Thanks for the post lacquer it is not wrinkling the primer, I get some off when I wipe it. It seems brittle and has chipped in a couple places, this is what started my concern and search for info. Mike
It is common for lacquer thinner to soften epoxy primer. The primer is cured if mixed properly, but stays "open" so the topcoats can chemically bite into it. Thats why epoxy primer is a good product. Sticks to everything and everything sticks to it.
Sounds like you need to quit using lacquer thinner. Sand off the overspray, you're blocking the car anyway, right? The chipping or brittle paint is concerning, were those areas prepped well, anytime I've used epoxy prime it was pretty tough, occasional bumping to align panels didn't phase it.
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