You can add distilled water to latex paint for finer paint misting.
If you need to paint large quantities of wood, an airless sprayer makes the job much easier. Unfortunately, you need to thin most common paint for use with an airless sprayer, to produce a fine mist for even coverage. While it is possible to literally "water down" paint for an airless sprayer, you'll get better results with specialized thinning agents.
Instructions
1. Measure your paint with liquid measuring cups. If you plan on watering down the entire gallon of paint, then just pour the entire container into a larger bucket for easier mixing.
2. Consult your airless sprayer's instruction manual to see how much you should thin the paint, as brands' thinning recommendations differ. In most cases, you'll just need to thin about 10 percent. If you don't have access to the instruction manual or if you simply want to water down the paint, start at 5 percent. Test the paint on a piece of scrap wood and add dilute the paint further if the 5 percent thinning doesn't work well enough.
3. Measure your ideal percentage of thinning agent using liquid measuring cups. One gallon is 128 fluid ozs. Therefore, if you're diluting a gallon of paint by 10 percent, you need to add 12.8 cups of thinner. Latex paints are water-based, so you can dilute the mixture with water. Tap water may contain chemicals that react with the paint, so distilled water is your best choice.
4. Stir the mixture gently with a paint stir stick for 10 minutes. Don't whisk the mixture; vigorous motion creates unwanted air bubbles. Once the solution is mixed, your paint is appropriately thinned for easier wood painting.
