Oil-based paint can be often difficult to work with when it's too thick. When applied with a paintbrush the thick paint can leave brush marks in the painted surface upon drying. A paint thinner allows for the paint to flow and smooth out after brush application. The standard mixing ratio is 227gr or 1 cup of thinner to 1 gallon of oil-based paint. Oil-based paints are desirable on a variety of surfaces, because they dry to a hard durable finish and are easy to clean.
Open a 1 gallon can of oil-based paint by sticking a flathead screwdriver under the lip of the lid and prying it open.
Pour 227gr of paint thinner into a measuring cup.
Pour the paint thinner into the can of paint. Most gallons aren't filled all the way to the top. If it is, you'll need to pour the paint into a mixing bucket before adding the thinner.
Stir the paint and thinner together for several minutes until the paint is noticeably thinner. Close the lid tight on the can by hitting the rim with the backside of the screwdriver.
Place your hands on each side of the can, lift it up toward your face and then rock it back and forth for several minutes. Reopen the can and mix it again.
Mix the paint before each use and throughout the paint process to keep it thoroughly mixed.
Paint thinner and oil-based paint are extremely flammable and should never be used near open flame. The vapours are also toxic and a respirator should be worn during use. A door and window should be opened to create cross-ventilation during use. A floor fan can increase the fresh air exchange. Wear rubber gloves when using paint thinner and painting with oil-based paint.