I know this is one topic that had me confused for a while. I have seen so many lessons where teachers add lots of water to acrylic paint to make drips and glazes and I wondered if this was a good idea. I had seen warnings that this could cause your paint to flake in the long run, so I decided to do some research because not knowing was bugging the hell out of me. 😉
I had read about the safe 30 percent water to paint ratio, but that doesn’t give you lots of playing room. As it turns out, it’s the quality of your paint that’s really important here (there I go again, preaching about investing in high quality paints).
If you are using cheaper paint, you can respect the 30 percent rule or, even better, add a Flow Improver acrylic medium to them. This won’t break down their acrylic binder and you can play with drips and washes without worrying if your painting will hold up over time.
If you’re using Golden paints, you can be way more bold with your water to paint ratio. How much depends on the colour you’re using. For instance, you might want to be a little bit more careful with pigments like Raw Umber, which has a high clay content, or the more dye-like Anthraquinone Blue. Interesting, right?
Golden has tested this subject matter thoroughly in this super interesting article. I highly recommend that you read this if you want to know what your paints are capable of.
Even though I’m not a very drippy person, I decided to play a little bit with it today, I like to know what I’m talking about. I tested the Liquitex paints with lots of water in my journal. If this portrait will flake off after a while, I’ll be sure to let you know!