Any damage to your needle can cause very bad paint spray patterns. It is important to keep your needle from getting bend and either straightening the needle or replacing the needle. The air cap and head assembly are on the front of your airbrush and they cover the tip of the needle. The purpose of these parts is to control atomization of the paint spray. The internal mix is when the air and the paint both mix inside of the airbrush. This will create a atomized fine dot spray pattern. This makes the internal mix a good choice for fine detailed work in your airbrush art. The point at which they come together is in the head assembly. The external mix is where the air and paint come together outside of the head assembly or the fluid assembly. When a person looks strongly at your artwork on the hood of the model car they can really see the capacity of the skills that you have as an airbrush artist. Or imagine that no matter what size your project is, even the fine details are brought out to the point that they demand to be noticed. All this can be done if an artist takes the time to learn micro airbrushing. The method believed to be used in this primitive form of airbrush art was the use of a hollow bone in which to spray the paint out of by blowing through it. While this is a very primitive method compared to modern day forms of airbrushing, it does still work. Take a look at children's airbrush art kits that require the child to blow through one end of tube to create the airbrushed art. Airbrush art can also be seen in magazines geared toward airbrushing cars or bikes and such. Making for much more precise content toward a more specific niche. Airbrush Technique Magazine is a broad spectrum magazine that is geared to teach techniques of airbrush art no matter what you are airbrushing. Airbrush Art On Automobiles By airbrushing art onto your automobile you can create a unique paint job that really shows off your style. Once you have the basics down on how to work the airbrush then you can pretty much create some great airbrush art on your automobile. It does not matter if you can draw or not.