An airless sprayer turns tip selection into paint engineering: the tip's orifice size and fan width determine how much paint flows, how finely it atomizes, and how wide the pattern lands. Latex paint, thick and fast-drying, is picky about all three. The right tip lays down a smooth, even film in efficient passes; the wrong tip spits, tails, or starves the surface. Understanding tip numbering and sizing logic makes selection a calculation instead of a gamble.
Reading tip numbers
Airless tip sizes are coded in thousandths of an inch of orifice diameter, with the fan width encoded alongside. A commonly seen format expresses the fan width as roughly twice the first digits in inches at a standard distance, followed by the orifice size: so a tip described as a 12-inch fan with a 0.015-inch orifice tells you both pattern width and flow rate. Larger orifice numbers mean more paint flow; the fan number describes coverage width.
The orifice primarily controls flow rate and atomization quality for a given paint viscosity and pump pressure. The fan width controls how wide each pass is. These are independent choices serving different goals: orifice for the paint, fan for the surface geometry.
Sizing the orifice for latex
Latex paints, being relatively viscous, need orifices in the mid-range of the tip spectrum to atomize properly without excessive pressure. Too small an orifice for the paint forces the pump to high pressure to push the viscous material through, which accelerates tip wear and can produce a harsh, over-atomized pattern with excessive overspray. Too large an orifice at normal pressure delivers more paint than the surface needs, causing runs and sags.
Match the orifice to the paint's viscosity and the manufacturer's recommendation, then fine-tune with pressure. Heavier-bodied paints and primers want the larger end of the latex range; thinner enamels and stains want smaller. When switching products, switch tips; running everything through one tip is the source of half of all airless complaints.
Fan width and surface geometry
Wide fans cover broad walls efficiently but waste paint on narrow trim; narrow fans suit trim, doors, and detail work but make wall coverage tedious. A practical kit includes a wide fan for walls and ceilings and a narrow fan for trim, with orifices matched to each paint. The fan width also affects film build: the same flow through a narrower fan deposits a heavier coat, which matters for hiding and mil thickness.
Overlap passes by roughly half the fan width for even coverage. The fan pattern is heaviest in the center and feathers at the edges, so the overlap evens out the distribution. Inconsistent overlap shows as striping; consistent technique with the right tip hides it.
Pressure, wear, and pattern quality
Set pressure to the minimum that fully atomizes the pattern with no tails, the unatomized streams at the fan edges that indicate starvation. Tails mean more pressure or a smaller orifice; a fuzzy, over-atomized pattern with excessive bounce-back means less pressure. The sweet spot is a soft-edged, even fan at the lowest pressure that eliminates tails.
Tips wear. An orifice that has eroded larger flows more paint at the same pressure and atomizes worse, showing up as gradually increasing flow and degrading pattern over a large job. On big projects, budget for tip replacement; a worn tip wastes more paint than a new one costs. Flush and store tips properly, since dried paint in the orifice ruins the pattern permanently.
Safety and cleanup discipline
Airless sprayers operate at thousands of PSI, and the spray can inject paint through skin, a medical emergency, not a workshop annoyance. Engage the trigger lock whenever not spraying, never point the gun at anyone, and use the correct tip guard. Treat the pressurized system with the respect its pressure demands.
Clean the system thoroughly after latex use; dried latex in the pump, hose, or gun causes the next job's problems. Flush with water until clear, then run pump protector through for storage. A clean rig sprays like new; a neglected one sprays like the last job's leftovers.
Tip selection is orifice for the paint, fan for the surface, pressure for atomization, verified by the pattern. Size latex in the mid-range, keep a wall tip and a trim tip, replace worn tips without sentiment, and respect the pressure. The finish will look sprayed by someone who knew what they were doing.
Related Guides
- Cleaning Airless Spray Packings to Eliminate Pulsing: Your airless sprayer used to lay down a smooth, even fan, and now it pulses: the pattern surges and fades with every pump stroke, leaving stripes on
- Straining Latex Paint to Eliminate Gun Clogging: A spray gun that sputters, spits, or clogs mid-coat turns a fast job into a slow one. Most of those clogs are not gun problems; they are paint
- Wet Film Gauge Thickness Audits for Acrylic Enamels: Acrylic enamel, the workhorse coating for trim, doors, and cabinetry, delivers its hardness, washability, and durability only at the specified dry
- Atomization Pressure Calibration for HVLP Clear Coats: Clear coat is where a paint job is won or lost, and atomization is where clear coat is won or lost. The spray gun's job is to break the liquid into