A: In an internal-mix airbrush, the air and paint mix inside the paint tip. This produces a thorough atomization or mixing, which results in a very soft, fine spray pattern. In an external-mix airbrush, the air and paint mix outside the tip, producing a coarse spray pattern.

Q: What is meant by dual-action and single-action?

A: These are two different types of airbrush triggers. Single-action airbrushes are activated by simply depressing the trigger; a preset amount of paint is automatically sprayed. To change the amount of spray, you must stop airbrushing and reset the needle adjustment screw. These are recommended for students because they are less expensive than dual-action. With the more sophisticated dual-action airbrushes, when the user depresses the trigger, only air is released; the second action of drawing back on the trigger releases the paint. This dual-action--down, then back--enables the user to adjust the volume of spray simply by manipulating the trigger and without stopping.

Q: What types of paints can be sprayed through the airbrush?

A: Any paint can be sprayed through the airbrush as long as it can be thinned to a flowable consistency (such as that of milk or ink) with the appropriate thinner.

Q: At what air pressure is the airbrush sprayed?

A: 25 pounds per square inch (psi) for artwork; 55-65 psi for T-shirts and automotive painting.

Q: Is an airbrush hard to keep clean?

A: To maintain the airbrush, simply flush it with the appropriate paint cleaning agent--Medea Airbrush Cleaner for water-based paints and paint thinner for oil-based paints. Never immerse or soak an entire airbrush. Follow up with an application of Medea Super Lube for continued smooth operation.

Q: Why are there different size tips for the airbrush?

A: Most airbrushes are adaptable to three different tips--fine, medium, and heavy--to enable different size/volume sprays and to airbrush materials of varying viscosity (thick or thin). When the tip is changed in an internal-mix airbrush, the needle must also be changed to correspond (fine, medium or heavy).