Internal mix airbrushes are the type most commonly used and can be identified by the fact that they have a needle running through the length of the airbrush body. This needle controls the size and the amount of paint sprayed. As the needle is drawn back and away from the tip (head assembly) of the airbrush, paint is mixed with air (atomized) and then released. The further back the needle is drawn, the more paint is allowed to exit.

Airbrush

The airbrush need be cleaned only in the areas which come in contact with paint; and the paint flows from the paint reservoir (gravity feed, side feed, or bottom feed styles) into the airbrush, around the tip of the needle and out through the head assembly. These areas must be kept clean for optimum performance of the airbrush. Some recommendations follow:

1. Choose the appropriate cleaning agent. For water-soluble paints, use Medea Airbrush Cleaner. For most non-water-soluble paints (automotive, artist's oils, etc.) use spray gun and equipment cleaner. (Use caution--This is toxic!)
2. If there is paint in the paint reservoir, pour it back into a bottle or container and spray out any excess--ideally into the Medea Overspray Eliminator or else into a paper towel.
3. Wipe the paint reservoir as clean as possible.
4. Fill the paint reservoir one-quarter full with the appropriate cleaning agent. With a No. 5 flat bristle paintbrush, slosh the cleaning agent around the paint reservoir to break down the paint. The cleaning agent will turn opaque as this is done. Be sure to get into all the nooks and crannies and, if you are using a gravity-feed airbrush, get down into the cavity at the bottom of the paint reservoir.
5. Spray this now paint-contaminated cleaning agent through the airbrush, and once again wipe the paint reservoir clean with a rag or paper towel.
6. Repeat steps 4 and 5 as necessary until the cleaning agent sprays clear.
7. Using new cleaning agent and a clean bristle brush, gently wipe across the paint tip to remove any build-up of dried paint.

TIP: Do not use cotton swabs--the fibers will release and make a mess!

Needle

Between color changes, you could stop here with the cleaning and then continue to paint. However, periodically and at the end of the workday, you will want to clean the needle that runs through the airbrush. Here's how:

As previously stated, the needle runs through the length of the airbrush. To find it, remove the airbrush handle at the back of the tool. You will see the back end of the needle protruding through a nut (needle chuck nut). Loosen the needle by turning this nut counter-clockwise. Then pull the needle out and carefully wipe it clean. (Be aware that the needle has a sharp point.) Before you replace it, you may want to give it a light coat of Medea Super Lube needle oil to facilitate smooth triggering. Gently slide the needle back. If you feel any resistance, it is most likely caused by the trigger being slightly out of place. Reset the trigger (main lever) and slide the needle forward until it fits snugly in the nozzle. Reset the needle chuck nut by turning it clockwise until tight. Replace the handle.

At this point, your airbrush should be thoroughly clean and in good working order. Daily and thorough maintenance of your airbrush will result in spraying that is smooth, consistent and hassle-free.