I only paint from the bottle on very small parts. For larger parts, I put a mix of paint and thinner in another bottle. Less for white and more for gray, etc.
I use Tamiya thinner, too. Mr. Hobby Leveling Thinner works just as well I am told, but I haven’t started using it yet.
Do you also add a retarder? I can’t find any Tamiya Retarder, but I have Vallejo.
Cheers
No, I’ve never seen the need to use one.
The Tamiya Acrylic Retarder is supposed to help the mutli-coat lifting problem as well. I have used it when doing large areas of brush painting. At a ratio of 1:10 a little goes a long way. If you are happy with your brush painting results without it - save yourself the five bucks. In my case it may have just been a confidence booster, but I am happy with the results.