Brushes are a necessity on most paint jobs for their ability to reach tight corners and cut in along trim. Sizes of brushes used for painting and decorating are given in mm or inches, referring to the width of the head.
Common sizes are:
- ⅛ in, ¼ in, ⅜ in, ½ in, ⅝ in, ¾ in, ⅞ in, 1 in, 1¼ in, 1½ in, 2 in, 2½ in, 3 in, 3½ in, 4 in.
- 10 mm, 20 mm, bob 40 mm, 50 mm, 60 mm, 70 mm, 80 mm, 90 mm, 100 mm.
Paint brush bristles come in two types: natural and synthetic. Natural bristles are preferred for oil-based paints and varnishes, while synthetic brushes are better for water-based paints as the bristles do not expand when wetted. Filaments can be hollow or solid and can be tapered or untapered. Brushes with tapered filaments tend to give a smoother finish.
A paint roller is a paint application tool used for painting large flat surfaces rapidly and efficiently. A typical paint roller consists of two parts: the roller frame and the roller cover. The roller cover is a cylindrical core with a “nap” covering that absorbs the paint and transfers it to the painted surface, the roller frame attaches to the roller cover. The roller frame is reusable; however the cover is typically disposed of after use. It is possible to clean and reuse a roller cover, but not if it has dried paint on it.
There are three types of covers that can be used for painting: wool, fabric and foam.
- Lamb’s wool covers are great for oil-based paints and all surface textures (smooth, semi-smooth, and rough).
- Synthetic fabric covers are great for water-based paints and all surface textures (smooth, semi-rough, and rough).
- Foam covers are great for oil or high-gloss latex paints and work well on smooth or textured surfaces.
Covers also come in a variety of nap sizes ranging from 3/16 in to 1.5 in. Shorter naps work better on smooth surfaces while covers with longer naps are used on heavier textured surfaces.
An airless sprayer works by pumping paint at a very high pressure, up to 3,000 psi, through a hose and out a tiny hole in the spray gun tip. The tip is designed to break up the paint evenly into a fan-shaped spray pattern. Spray tips come in multiple sizes for a variety of applications, for example:
- 413 – interior latex
- 515 – some interior latex, some exterior latex
- 517 – exterior latex
- 311 – oil-base stain and water sealer on decks and fences
An airless sprayer simplifies painting in two ways: First, if you want to speed up a job that requires several gallons of paint, you can apply it twice as fast as with a roller or brush. And second, if you want a glass-smooth finish on woodwork or doors, the airless sprayer can lay the paint on flawlessly with no stipple or brush marks that can be left by rollers and brushes.
An HVLP (High Volume Low Pressure) spray gun applies finish at relatively low pressure (4 to 10 psi); about one-tenth that of a conventional high-pressure spray gun (25 to 80 psi). This means the finish hits the work at a much slower speed, so more of the product sticks to the work rather than bouncing off and creating a fog. Depending on the finish and the gun being used, as much as 90 percent of the finish will stick. That’s almost twice the efficiency of a high-pressure gun.
Two types of HVLP guns are available: turbine-driven guns and compressor-driven guns. Sprayers that use compressed air are called conversion guns or compressor HVLP guns. They convert high-pressure air coming from the compressor to low-pressure air in the gun. Compressor HVLP guns typically require a large compressor (at least 3 hp) and line filtration for moisture and oil. These guns are preferred in industrial settings because they’re more economical to run and can apply finish more quickly.
In electrostatic spray painting, the atomized particles are made to be electrically charged, thereby repelling each other and spreading themselves evenly as they exit the spray nozzle. The object being painted is charged oppositely or grounded. The paint is then attracted to the object and wraps around the surface giving a more even coat than conventional spray painting, and also greatly increasing the percentage of paint that sticks to the object. This method also means that paint covers hard to reach areas.
Electrostatic paint will stick to any surface that is conductive. Metal definitely. Wood has water in it, and the wetter the wood, the greater the positive charge. Surfaces that include plastic, stucco and wood that are old and very dry will need a thin coat of conductive adhesive promoter applied before painting.