Believe it or not, there is a life to your airless spray gun tip. All airless spray tips will wear down under normal use. The more solids within the paint you're spraying, the more abrasive the paint is as it comes out of the tip under high pressure. This means that over time the opening that paint comes through will become larger. Most paint tips are made of high grade tungsten carbide. Tungsten carbide is a very hard material that extends the life of the spray tip beyond what it would be if it was using stainless steel. Tungsten carbide only extends the life, but every spray tip will wear out over time.
A worn out airless paint spray tips will show itself in how it lays your coating on a surface. The spray pattern width, the 'fan', will decrease as the spray tip wears out. The following graphic shows you what that might look like. Notice the fan getting smaller. What also happens is more paint begins to come out of the tip. A painter will begin to spray more paint than is necessary which increases paint costs. Also, by placing more paint on the surface you're covering, you risk the possibility of orange peel, runs, bubbles, or other issues that could degrade the final finish. According to Graco, when a tip that had a 12-inch fan pattern is reduced to a 9-inch fan when worn, it will output 40% more paint on 25% less area. You can see that it's a recipe for waste, costs, and maybe disaster (repainting a job).
If your spray pattern begins to change, shorten and widen, making it harder to overlap spray, in an effort to achieve consistant thickness of your coating, then it's time to change your airless spray tip. If you don't you'll easily waste enough money, in extra paint, that could have paid for that new tip.
If you have any questions, or need assistance choosing the right paint tip for your job, reach out to us, we'd love to help.