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Hi Stan, Unfortunately I don't think there is much you can do about it right now. At least no guaranteed fix. Many of the 1K enamels have a sensitive recoat period where lifting can occur when you put the fresh coat on top of an uncured base. A while back I asked PPG specifically about recoating OMNI 1K since it is not mentioned on the tech sheet. Here's my question: Comment/Problem Description:
What is the safe recoat period for OMNI MAE acrylic enamel (w/o hardener)? There is nothing to indicate any recoat sensitive period in the tech sheet. It used to be that uncatalyzed enamels were sensitive to lifting upon recoating after a short dry time and before full curing perhaps months later. I have noticed that DuPont's NASON FastDry acrylic enamel (uncatalyzed) indicates recoating after 48 hours. Can MAE (w/o hardener) be similarly recoated without danger of lifting? And here's PPG's answer: Thank you for your interest in PPG products. There is no safe recoat period for uncatalyzed MAE. We do not have any recommendations for recoating uncatalyzed MAE. The best recommendation would be to put a waterborne primer over the uncatalyzed MAE and then recoat with MAE, still there is no guarantee it will not lift. It sounds like you got a dry spray at the edges which can occur if you move the gun in an arc such that the gun-to-part distance is greater at the edges. You need to keep a constant distance (about 6-8" for HVLP). Next time also try a technique called "banding" where you spray a first band of paint all around the edges, parallel to the edges, before your normal coverage begins. That gets some initial paint on the edges before anything else. You also want to carry your regular stroke out beyond any edge before letting the trigger go. I don't know anything about the "waterborne primer" that PPG mentions so I can't address it. You probably could recoat it anyway after a few months of cure but just how long is long enough is not well defined at all. Plus it depends on temperature. If you are seriously considering a possible recoat, here's what I would recommend: 1. Spray a test panel now for a future trial sprayout.
2. This summer try recoating your test panel to check for lifting. 3. If no lifting occurs, then proceed with recoating your truck where necessary. I'd do only complete individual panels where needed, cleaning and sanding beforehand. No guarantees here. I've never tried it. The other option you have is to try a recoat on a single panel only and see if it lifts. If it doesn't, fine. If it does, then you'll need to strip it completely and start over on that particular panel. I don't see any other choices for you. "Color sanding" and/or compounding could smooth the surface but you would never be able to obtain any gloss afterwards. The 1K enamel is simply to soft for that. That's the downside of using uncatalyzed paints - early repair of errors can be troublesome if not impossible.  Rod
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