Years ago my front door was painted with Kelly-Moore “Acry-Shield 100% Acrylic Exterior Semi-Gloss Enamel”. Recently a so-called professional painter painted over it with Sherwin Williams “SuperPaint Paint and Primer; Exterior Acrylic Latex”, with no separate primer. The result is a disaster; the paint is bubbling and peeling. I assume the acrylic latex is not compatible with the acrylic enamel. What would be the best way to fix this? I’m assuming I need to at least strip off the latex down to the original enamel (chemical stripper? sanding only?), then use an appropriate primer (what kind?) and an appropriate color coat (again what kind?).
BTW don’t suggest having the original painter fix this. I already tried that; they sanded it and repainted with the same latex, and the same thing happened again after a few months. I’m done working with those incompetents.
If the original paint was oil-based, which I’m guessing it is (I’m not familiar with that particular paint, I tried to look it up but I didn’t find any information), then the original idiot painter should have used a separate primer designed to separate the new water-based paint from the original oil-based. Kilz is a good brand for that.
If the new paint is bubbling and peeling, I would start with a scraper to get that off. Then sanding or chemical stripper, either one. I think you only need to get the new paint off. Once you have a smooth surface free of the new paint, prime with Kilz or equivalent, then paint.
I strongly recommend 2 things: if you use chemical stripper, take the door off the hinges and use the stripper outdoors or maybe in your garage with the door open. Be sure to protect your lungs with a chemical-proof respirator, your eyes with goggles, and your hands with butyl gloves. Wash the stripper residue off with 0000 steel wool and mineral spirits, let dry, sand as necessary. Then do the re-paint also with the door off and set on a horizontal surface, to get a good finish, especially if you are using a brush instead of a spray machine. Painting a door vertically guarantees that you will get drips that you will never see until they are dry.
I am not a professional, and this is all IMHO.
Good info from @Roderick_Femm.
What is the door made of? You might get it powered sanded. Pricey and the door goes to the shop, I guess. I can’t imagine they’d do it on site. Of course the door material would be critical.
Yes, priming is crucial for paint to work properly in my experience.
Also, MOHO
ETA…use a bonding primer for difficult surfaces. Kilz may be one. Not sure.
Stripping is more difficult than sanding, you run the risk of gouging or deep scratching with your tools unless you are experienced with scraping tools.
KIlz is a good primer, fairly sandable, and dries fast, so if you need to fill low spots,(scratches or flaws) you don’t have to wait forever. Small “weiner” rollers can give you a very nice texture, not as perfect as spray, but better than brush finish, which may still be needed if door has detailed mullions etc. You can also roll it with the door hanging and you wont need to mask off or protect areas as you might with spraying. (random handyman here)
I have employed a lot of painters. I don’t think ‘professional’ painters use ‘paint and primer in one’. All in one products are for convenience not performance.
Acrylic isn’t oil, but when painting over a different product it is standard to roughen the surface and use an appropriate primer.
Stripping / sanding down the messed up surface is the only solution now. Sanding off old paint is a pain. Sanding off recent paint is even worse. Everything is going to gum up. A power tool with wire stripping wheel might work better. I really don’t think scratching is that significant a concern with stripping, a profile is s pain to strip whether by you are doing it by scraping or sanding.