Conventional spray: 30-40% transfer efficiency, best atomization. Airless spray: 150-250 bar, high efficiency. Electrostatic (liquid): 60-90kV, 60-80% efficiency. Robotic painting: 6-axis robot — standard in automotive. Each method has different coverage and quality characteristics for different part types.
By function: primer, intermediate, topcoat, clear coat. By resin: polyurethane (durable, auto refinish), acrylic (fast drying, OEM), epoxy (best adhesion), alkyd (cheap), nitrocellulose (fast dry, being phased out for environmental reasons).
Runs: too thick paint. Orange peel: wrong thinner. Pinholes: solvent flashes too fast. Blistering: moisture under coating. Blushing: high humidity. Lifting: subsequent coat dissolves previous coat. Spray booths require temperature control (20-25°C, RH 40-70%). Waterborne paints now replace solvent-based, reducing VOC by 90%.