43. A key point of painting often overlooked is that you must have a clean and dry air source. Water is common in compressors due to humidity and temperature changes, and it can play havoc with drying times, adhesion, and reliability. An expensive refrigerant-style air dryer is the choice of most pro facilities, but an affordable option for quality, dry air that we can recommend is a four-stage desiccant dryer from Eastwood. Check out www.PopularHotRodding.com for more on this system.