The Wagner 404 is a commercial-grade airless paint sprayer. As its name implies, an airless sprayer applies liquid paint or other material without using compressed air to propel it. Instead, a piston compresses the paint itself and delivers it under high pressure through a hose and out very fine orifices in the spray gun's tip. Airless sprayers create far less overspray than compressed air and use paint more efficiently. The Wagner 404 sprays .33 gallons per minute at an operating pressure of up to 2,500 p.s.i. It applies paint, primer, stains and preservative, as well as other liquids like pesticides and liquid fertilizer.
Practice on a test area to determine the best pressure for the material you are spraying. Turn the pressure control knob to the lowest setting and turn the Prime/Spray control to "Spray." Turn the pressure control to the highest setting and release the spray gun safety switch. Spray a practice area. The spray will appear too light if the pressure is too high. If the pressure is too low, the paint will spatter rather that form a uniform, fine spray. Use the lowest possible spray pressure for the material you are spraying. Latex paints and stains usually require a high pressure.
Smooth, even strokes are the key to successful airless spray painting. Spray from a distance of 10 inches to 12 inches from the surface. Do not flex your wrist to move the gun during strokes. Move your entire arm and maintain the spray gun at a 90-degree angle to the surface at all times.
Trigger the sprayer on and off for each individual stroke. Pull the trigger to begin spraying after your arm is already in motion. Release the trigger as you reach the end of each stroke and keep your arm in motion beyond the end of the stroke. This ensures even coating and avoids buildup of paint at the beginning and end of strokes.
Short Term Storage
Suspend spraying for more than one hour but not longer than overnight; perform a quick, short-term storage procedure to prevent clogs at startup. Lock the spray gun trigger and turn the pressure control to the minimum setting. Turn the Prime/Spray control to "Prime." Turn the motor off and unplug the sprayer. For latex materials, leave the suction tube in the paint and pour a 1/2 cup layer of water on top of the material in the container to prevent drying. For other materials, leave the suction tube in the container and seal the container with a piece of plastic. Wrap the spray gun in a moist towel and enclose it in a plastic bag.