There are two main types of powered paint sprayers: airspray and airless. Airless applicators can be further subdivided into two kinds, based on the pump they use: diaphragm and piston.
Also known as HVLP (high volume low pressure) units, they combine a large quantity of air with the desired covering material. The low pressure allows smooth coverage with very little overspray. They're best used for smaller areas where a glossy smooth finish is desired, such as shutters and cabinets. Other airspray models use an air compressor.
The most common type for the do-it yourselfer, paint is pushed under high pressure through an applicator tip, eliminating the need to reach for a bucket or tray to reload. Since the pressure is provided by a pump rather than air, overspray and waste are reduced. Airless sprayers are great for painting walls or other large areas, as well as smaller areas. The paint capacity ranges from one quart in a self-contained handheld sprayer to a basically infinite capacity for units that pump straight from the paint container. In addition to handheld, units are available for use with a shoulder strap/backpack or mounted on wheels for portability.
The basic homeowner/do-it-yourselfer models use a simple diaphragm pump. The painter primes and delivers material to the applicator.
A piston pump enables the user to spray conventional coverings but can also deliver thicker liquids, such as block fillers.
At the high-end of the power painter spectrum, double-stroke piston units deliver material on both the up and down piston strokes for maximum power. Consistent pressure delivery at slower speeds provides good coverage and prolongs the life of the machine itself. Depending on the model, more than one user can paint at the same time by adding additional hoses. These models are usually the machine of choice for professionals.
First determine the types of jobs you'll be doing with the paint machine.
Large, even spaces such as walls require less power than irregular areas like lattice or fencing. Various spray tips adjust and direct the paint just where it's needed. Multiple speeds let you turn down the volume for smaller, tighter areas.
When it comes to how much you need — from a one-quart handheld sprayer, to a one-gallon backpack unit, to a five-gallon piston pump model on wheels — you'll find one that fits your project.
Painters with higher psi (pounds per square inch), GPM (gallons per minute), and HP (horsepower) are able to spray thicker materials. Spray tips are designed to accommodate each type of covering. The basic classifications of thickness are:
Indoors or outdoors, if you're working from a ladder make sure the length of the hose or cord is sufficient. Smaller painters are available in corded or cordless models. Check the battery run time on a cordless unit to make sure it's enough for the job. If you don't have access to electrical power, use a generator.
Make the most of your painter and your project. Remember the following: