How does a spray gun operate?

A spray gun operates primarily by utilizing compressed air to atomize coatings, allowing for a fine mist of paint to be evenly distributed over a surface. This process involves the compression of air which, when triggered, mixes with the paint and forces it through a nozzle. The force of the air is crucial as it breaks the liquid paint into tiny droplets, creating a smooth application that minimizes runs and drips.

In the context of the other options, while gravity can be involved in some spray systems (such as gravity-fed spray guns), it is not the primary mechanism in most professional spray gun designs. Manual force is not typically used in spray guns; instead, they are designed for consistent and controlled application without the exertion of force by the user. Heating the paint before application is not a function performed by the spray gun; instead, it may be more common in specialized equipment rather than standard spray guns used for painting and refinishing tasks.