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Epoxy over EDP Process?

I haven't been able to find a definitive answer as to the process for painting over EDP. I will use the lacquer thinner on a rag test to make sure it's good, and if it is, how should I prep? Ideally, I would like to scuff with the appropriate grit, spray epoxy 1:1:1, then straight to base/clear. But in my experience, EDP is thin and I will sand through it in spots no matter what grit I use. So what grit should I use in this approach?
If the EDP is in real good shape and OEM you can maroon scotchbrite and seal, done every day. I usually 320 DA lightly, then scotchbrite, because of scuffs or defects. Is this a collision job or restoration? If it is a restoration best to strip and put 2 coats epoxy, IMO.


Paint Fanatic
Staff member
Both the above is perfect advice.

Since the e-coat tested good you can sand with 180, 320 or red pad and shoot epoxy.
If on your C10 Id take to bare metal, one thing my blaster told me when he did my box this past weekend was that on one of the fenders there was a chalk or marker writing under the ecoat. Its just too big of a gamble with these Taiwan repro panels to leave it in my opinion.


Paint Fanatic
Staff member
Thanks for the input everyone. Sounds like I better strip the EDP since they will be repro panels.
I have always had mixed emotions about this question since it passed the lacquer test.
Reason is I have been inside the ecoating automation plants and we cannot duplicate the perfect cleaning of metal before ecoat that the automation process does
But!! the million dollar question is how are the offshore people doing it.
Maybe we can do better, I just don't have the answer.
we had some EDP panels come in that almost looked like rust underneath, like pebbles, maybe a 3x4 inch area. Sanded it to bare metal and it was just the e coat. The biggest problem is when the cleaning agent gets too hot and the parts dry before getting rinsed. But the e coat will most probably be peeling off it that happened. They say if the oxygen cannot get to the rust it cannot continue to grow.


Paint Fanatic
Staff member
Had same thing happen on a door with my epoxy, shop was in 40s or low 50s that night and in morning shot epoxy with no heat.
Moisture on metal and 3 months later rusting under epoxy.