The Difference: bottom feed and gravity feed spray guns

Spray guns are essential tools for apply­ing smooth, even coats of finish, whether you’re working with lacquer, paint, shel­lac or other materials. Two common types are bottom feed (also known as siphon feed) and gravity feed spray guns. While they both serve the same general purpose, they differ in design, performance and ideal applications.

A bottom feed spray gun has a cup mounted beneath the spray gun body. When the gun is triggered, air passing through the gun creates a vacuum that draws the finish up from the cup and into the spray nozzle. Because this system relies on suction, bottom feed guns typically require more air pressure to operate effec­tively. They’re particularly well-suited for spraying large quantities of finish, since the cup can be larger and doesn’t affect the bal­ance of the gun as much. Bottom feed guns are also commonly used in automotive and industrial settings, where a high volume of material needs to be applied quickly.

In contrast, a gravity feed spray gun has the cup mounted on top of the gun, allow­ing the finish to flow down into the nozzle by gravity. This setup requires less air pres­sure, resulting in better transfer efficiency and reduced overspray. Gravity feed guns are often preferred for fine finishing tasks — found in woodworking, cabinetmaking or automotive touch-ups — where control and material conservation are priorities. Because the finish is fed into the gun more easily, gravity feed models can also handle thicker materials more effectively, without requiring thinning.

Choosing between the two depends largely on the task at hand. A bottom feed spray gun is ideal when you’re working on large-scale projects that require extended spraying time without frequent refilling, such as painting fences, walls or large fur­niture pieces. The larger cup capacity and balanced handling make it a workhorse for high-volume jobs.
On the other hand, a gravity feed spray gun excels in precision work and is bet­ter for smaller-scale or detail-oriented jobs where finish quality is critical. It’s easier to clean, uses less finish overall and produces less overspray — making it a popular choice for woodworkers, especially in smaller shops or when working with expensive or limited-quantity finishes.