GF13-017NJII
...Currently I'm working on learning how to hand brush Tamiya Acrylic. I've been collecting info from search results from the forum and I'm going to try to congregate them into one place, and if I successfully learn then I'll try to make a tutorial for others since I know others that have Tamiya acrylic highly available but no airbrush for the time being...
I use Tamiya acrylics all the time. They are formulated for airbrushing and are meant to be thinned to some degree. The best advice I can give you is to use Tamiya's proprietary acrylic thinner to thin the paint to apply it. I do this in one of two ways, depending on my mood.
One is to keep a little jar of the thinner on hand, dip the brush in the thinner and then into the paint, and then apply it. I also use the jar lids as little palettes. Shaking the jar throroughly deposits a little paint on the inside, so that's my supply of paint, that's what I'll dip the brush into.
The other is to use my ceramic palette, and to mix a batch of the color in a well on the palette. I will put some paint from the jar into the well, then add the thinner with an eyedropper.
Over the years, as I worked with Tamiya's acrylics and learned these things, I tried other thinners, particularly water, and isopropyl. Neither worked for me; the paint still clumped on the brush and on the piece. And when I would try to apply a second coat, it would lift off bits of the first coat. And this is over Tamiya's fine surface primer. The issue was thinning, and thinning with the right thinner. As I learned to apply Tamiya acrylics with the airbrush, I applied those lessons to hand-brushing.
Now, I can get coats of paint as thin as if I had applied them with the airbrush, using this method.
In the previous post, Rambo mentioned using a wet palette, and using Vallejo's paints. I also recommend using a wet palette, with other acrylic brands, like Vallejo, Andrea, and with craft store paints, any acrylic that can be thinned with water. I use a wet palette, too, with those water-soluble acrylics. A wet palette lets me keep a batch of paint workable past the end of a session. It's basically an air-tight and water-tight container, with a sponge to hold water and provide the moisture, and a permeable membrane that serves as the palette, keeping the paint fresh. There are commercial brands available, but I made one out of a take-out container, a kitchen sponge, and brown package wrapping paper:
Hope that all helps!
Best regards,
Brad