Do you varnish your models?

[m0nolith]

Yeah, the same thing happens with washes. If you thin with water and use a brush, if you let it pool it tends to dry white. Even if you airbrush this can happen.

If you need to thin an acrylic, I suggest using the appropriate medium. Acrylic medium/thinner for acrylic varnish, lacquer thinner for lacquer varnish, etc. Or simply wick excess away from your brush on a paper towel so your brush isn't dripping in varnish, then try to spread what's on your brush over a larger portion of the model. Varnish is clear so it's not like you'll have to worry about thick varnish covering up details, unless you absolutely slop it on.

Was using Vallejo Satin varnish, and I tried to mix it with two mediums, Vallejo regular acrylic thinner and vallejo airbrush thinner. Both were better than water, but both ended up whitening no matter how much excess I washed off. Think the problem may be that im varnishing metal.

In the end I went with very thin coats of pure satin varnish and that seemed to solve the problem. I am loving the results tho, the shading really looks great with it!