Checking for the Proper Amount of Fluid Delivery in an Automated Paint Delivery System
Spray guns are simple in that they require air and fluid to operate. The amount of fluid will dictate the speed of painting and to a certain extent depth of coating applied. When it comes to issues with achieving a desired finish due to a spray gun you have to determine is the issue at the gun itself or is it an issue with the supply of material or air to the gun.Typically air is the biggest limiting factor in spray operations, the compressor that your shop has must have enough air production to support all the air powered tools in your shop. However, if you have determined the amount of air that you are using at peak (meaning when all air tools are run in your shop) and you still are having issues with spray coverage you may want to look at the amount of fluid being delivered to the guns. This is especially pertinent when you are using an automatic system to feed your spray outfit. For example, if your using a diaphragm or piston pump that is feeding your spray guns from a 5 gallon drum you will want to ensure proper fluid delivery to the spray guns. If the spray gun is not getting the appropriate amount of fluid you will get a coat that is uneven or spraying that is inconsistent in amount.
The best way to test for the proper amount of fluid and make sure the supply is adequate is to completely turn off the atomization air to your gun. Then you can trigger the spray gun(s) and observe the fluid flowing from the spray gun(s). If there is an appropriate amount of fluid being delivered to the gun the stream will travel 2 feet or so in an arced pattern (assuming your standing and holding the gun at waste level). If there are multiple guns you have to test the guns all triggered together so that you know your supply apparatus is providing sufficient fluid for your spray guns to work efficiently.