Last summer/late, I sanded my older wooden garage door exterior then used 2 coats of oil primer before finishing with a very dark Sherwin Williams “Aqua” latex paint.
I didn’t paint the inside of the door but did seal all edges/sides.
Looked beautiful for a month or so then coastal damp weather was on and the paint started to bubble. After painting, can’t remember if next day or later, the weather was humid moist maybe a few drizzles.
Now I am sanding off bubbles and wonder what to do next as under the spots the wood looks bare. Where did primer go? I am stuck. Do I strip it all and start again? Do I paint over removed bubbles?
The paint peels in areas after I sand…did none of it adhere?
I also put a clear crack filler around panels last year which took forever to dry…7 days plus. In some spots it still had a bit of stickiness when I painted over it but I was told that was fine. So do I remove that as well?
Can’t say I know how to prime just bare spots then repaint. Worry it will just keep bubbling. There doesn’t seem to be bubbles on framing of door around all panels just on panels so I wondered if I could just leave that area alone. Stuck!
The problem arises from the dark finish coat transferring heat through to the coats of primer beneath. The primer react to the heat as if you had used a heat gun on it and lets go especially if there was old residue of old linseed oil based paint. This softens and lets go and with the surface tension that is created when acrylics dry (they pull together as they dry) it tends to pull off unsound coats beneath. Also the water base paints don't adhere well to oily primers and tend to peel eventually. Best to used an acrylic primer and lighter finish colour to reflect rather than absorb heat.
