I feel your pain. I've used Acryl quite a bit over the years, most of the time with good results. But, I've surely had my share of runs or sags, too. Generally, a fresh bottle needs no thinning to shoot well. Other times, just a drop or 2 of thinner to 1/8 oz. of paint. If your surfaces to be painted are too smooth, with no tooth for the paint to grab onto, you may get results like you experienced. I try for multiple thin coats, without burying the details. I've used flat white & flat black as base coats for a few model cars, but I was a bit surprised that the white primer had a slight sheen to it, not flat. I prefer flat white.
One thing to note, once cured, Acryl is very tough & almost impervious to hotter solvents. Over the past few years, I use it as a barrier coat to prevent hotter lacquer top coats from eating into the plastic.
BUT!..... All of the work you're doing is really looking great!
Steve
