All Spray Guns are tools designed to exacting specifications and (especially for automatic Spray Guns) have a large number of small parts that need to work together to make your spray cycle efficient and leak-free. But even with as many as 40 parts in a single gun, only a few are high-use parts that experience wear with each firing cycle. About 90% of problems are caused by general wear and tear of these parts, including clogs, leaks (air or material), intermittent spraying, and uneven spraying. Here's a quick troubleshooting list of common issues and their associated fixes. Here are some common Spray Gun problems and how to fix them.
When the gun is not triggered, the nozzle tip drips or leaks: this means the needle and nozzle are not seated properly. This can be caused by wear, damage, blockage or debris. Remove the nozzle and make sure there is nothing in it that will prevent the needle from seating. After resealing, if there is still a leak, you will most likely need to replace the needle and nozzle. These should be replaced at the same time.
Material is not flowing: There is a material blockage somewhere in the gun or in your supply. If you're using a gravity gun, check to make sure your cup fits properly. If yes, check to see if your cup is venting. There should be a small hole near the top of the gravity cup through which air can enter as the material exits; make sure the hole is not blocked. If running feed, check your feed pressure. If the pressure is good, make sure it retracts from the nozzle by watching the needle as you pull the trigger. If not, then you will need to replace the needle assembly. Note that additional spare parts may be required.
Package leaks: You need to adjust the package. Simply tighten the packing nut until the leak stops. If this doesn't work, the needle seal needs to be replaced. Note that additional spare parts may be required.
Asymmetrical spray pattern: This is most likely due to a clogged, dirty or damaged air cap. If you're not getting even airflow from all the holes in the air cap, the way you spray will suffer. Remove the air cap and clean it with solvent and a brush from the maintenance kit. Do not use picks to clean the holes as they are easily damaged. If you do not get a good spray pattern after cleaning the air cap, it is damaged and should be replaced.
Airbrush problems end up affecting everyone who uses some kind of coating system. With a little knowledge and prioritized maintenance, you can better reduce problems and save money and time.
