Walmart Paint
I have been using airbrushes for about 3-6 months now and had the same problem with this style of paint. What I found out is that I had the answer setting on a shelf in my living room. I have a Central Pneumatic airbrush and an Iwata Eclipse airbrush, both being dual action. I couldn't seem to get the paint to flow well with either brush, so I purchased a .5mm needle for the Iwata and still no joy. Then it dawned on me that the paint wasn't like Createx, and being 58 years old didn't have the time to figure it out. So I went to an old stand-by. I had a single action CP airbrush with 5 siphon feed bottles and decided to give that a try. To my amazement, it worked the first time without thinning the paint. The coat was very smooth and looked very good for what I was doing. I make fishing lures here in Kansas and my setup is now complete. I hope this helps the rest of the community with whatever problems you're having with the Walmart paints.
Sincerely,
WBPappy