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Choosing the right tip can be as important as having the right pressure gauged on your sprayer. Larger tips generally require more pressure, but can cover more ground effectively. Narrower tips, on the other hand, are best for precision work. If you're unsure about the sort of tip you should be using, contact a hardware professional and give her the details of your project. Latex paint works for airless sprayers, but it must first be thinned out in order to flow easily through the nozzle. Add 1/4 cup of water or chemical thinner for every gallon of paint you're using, then mix the two together thoroughly. You may have to experiment with different thicknesses of paint. Load some into your paint sprayer and check the coverage. If it's not spraying evenly, you may need to add more thinner. Latex paint is the default paint for airless sprayers. Chemical thinners are available from paint and hardware stores as well. These work more effectively than water and don't work against the paint's default properties. The type of paint you use for your project will depend on the surface. No matter how well you mix the paint, there may still be little clumps of solid paint. It doesn't take much to clog an airless sprayer nozzle. Take a strainer and strain your paint into another bucket, catching the solid bits and discarding them. An airless sprayer draws paint from a hose. Attach your siphon hose to the back and place it gently in your paint bucket. It's a good idea to do this prior to priming. That way, you'll be able to tell priming is done because paint will start coming through the nozzle. All airless sprayers require priming before they're ready for use. Luckily, this is a fairly straightforward operation, as many airless sprayers will have a "Prime" setting. If your airless sprayer isn't priming successfully, it may help to give the device a slight tap with a hammer. This can loosen any clogged paint inside the sprayer. Keep the nozzle face downward in a bucket to account for paint drips while you're getting the sprayer ready. Making sure your sprayer's in working order before you use it can help prevent big messes. Check the hose for microfractures. Check the nozzle and make sure the filter is clear. Give the paint a quick test run on a surface to make sure the paint's being distributed evenly.
Pick the right tip. Thin the paint. Strain your paint. Set up the siphon hose. Prime the pump. Give your sprayer a quick check before each use.