If you are using Createx Colors, here is the commen t form the manufacturer... "Createx Airbrush Colors work best out of the bottle with a 0.5mm tip-sized airbrush operated @ 40 � 50 PSI." http://createxcolors.com/airbrushcolors.html If you are using this then the pigment is too large for your brush. These come in transparent, not really intended for microns... they can be reduced. Just because it's transparent doesn't mean it will go through the brush! If you are working with the PDF tutorial you will see on page 3 under equipment used that the painting is done in Com-Art colours. Similar paints would be Createx Illustration, Golden high flow, Schminke but not Createx colors. Createx Illustration... Much better for what you are wanting... http://www.createxcolors.com/illustration.html If it is over two years old give it a try but a REALLY good stir first. Wicked should be OK.