Conventional spray guns use compressed air to atomise paint and apply it to a surface. Air and paint enter the gun through separate channels and are mixed using an air cap to form a controlled spray pattern.
Paint can be fed to a conventional spray gun via different methods. These vary from a cup attached to the bottom of the gun which supplies the paint by suction (suction fed), or a cup on the top of the gun which supplies the paint by gravity (gravity fed). Gravity fed guns generally require less air than suction fed guns and generate less overspray.