I use acrylic washes over enamels that have a coat of future.
I use an eye dropper kind of thing, and put 5 drops water, 2 drops liquid dish soap and 1 drop paint in a small bottle cap (like off a Coke bottle). I stir it with a toothpick.
I test it in a place or two (it dries quickly) and if it rubs off fine, I go with it. If the wash has trouble coming off (I use Qtips), I add another drop of soap.
So far it works well.
Jon Bius
AgapeModels.com- Modeling with a Higher purpose
"For I know the plans I have for you," declares the Lord, "plans to prosper you and not to harm you, plans to give you hope and a future." ~ Jeremiah 29:11