Check nowSize the spray tip according to the tip rating of your sprayer. Make sure that the sprayer can support the tip you are planning to use. If you plan on using multiple spray guns on your job, pick a tip size that matches the multiple gun tip rating of your sprayer.
Choose a tip with an orifice size rated for the paint or coating you’ll be spraying. Light coatings such as lacquers, stains, and enamels require a small tip, while heavier coatings such as texture require larger spray tips. Many paint manufacturers will specify recommended spray tip sizes on the container or product specification sheet.
Case in point – a 317 tip and a 517 tip both have the same orifice size – 17-thousandths of an inch. But, the 517 tip sprays a 10-inch-wide fan, while the 317 sprays a 6-inch-wide fan. Because the same amount of paint is leaving the orifice of the spray tip, but is being dispersed across a wider fan, the 517 tip will deliver a thinner coating with less mil build.
Most spray tips are identified by a three-digit code. The first number, when multiplied by 2, tells you how wide of a fan the tip will create when sprayed at a distance of 12 inches from the surface. The second two numbers are the orifice size of the tip, in thousandths of an inch, that determines how much fluid will leave the spray tip. For example, a 515 tip will spray a 10-inch-wide fan and have a 15-thousandths of an inch orifice. It’s the combination of fan-width and orifice-size that determines how thick of a coating you’ll spray.
While Graco tips are made out of the highest grade of tungsten carbide – the most abrasive-resistant material available – all spray tips will wear with normal use. All coatings contain solids that are abrasive -- some more than others. Using a worn tip can cost you hundreds of dollars in wasted paint and labor; because when a tip wears the size of the tip orifice increases and the fan width decreases. This forces more passes to cover the surface, more labor, increased overspray, and a substantial waste of paint.
For example, assume that paint costs $15 per gallon, labor costs $25 an hour and the contractor sprays 5 gallons of paint per hour. If the contractor uses a worn tip (a 12-inch fan pattern worn to 9-inch) he will spend an additional $36.25 in wasted paint and labor per hour. If the painter continues to use the worn tip, it will cost him around $300 per day!
Always turn down the pressure as low as it can go, while still spraying a good spray pattern. This not only saves paint, by reducing overspray, but it also reduces tip wear and prolongs pump life, saving you money.
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