Runs, sags, and wrinkles in coatings are primarily caused by which factor?

Runs, sags, and wrinkles in coatings are primarily caused by using improper spray technique. When applying coatings, especially through techniques such as spraying, the angle of the spray nozzle, distance from the surface, and the speed at which the applicator moves can greatly influence the uniformity of the application.

If the spray technique is incorrect—such as spraying too close to the surface or at an improper angle—this can result in an uneven distribution of the coating. When too much material is deposited in one area, it can start to run or sag, leading to those undesirable defects. Additionally, improper technique can disturb the coating before it has a chance to cure properly, thus creating wrinkles.

Understanding the importance of proper application methods is crucial for achieving a smooth and high-quality finish in coatings. This involves not only mastering the technique but also understanding factors such as pressure settings, the viscosity of the coating, and environmental conditions during application to avoid defects.