Airless Spraying—From Pump to Pattern | Article 3 of 18
How to Choose the Correct Airless Tip Size
The Right Tip Starts with the Coating—not the One Already in the Gun
There is a familiar method for selecting an airless spray tip: reach into the toolbox and use whichever one happens to be there.
Sometimes that works. Sometimes it produces tails, runs, slow production, excessive overspray, poor coverage, an overworked sprayer, or a coating that refuses to atomize properly.
The correct tip is not selected by habit, popularity, or the number stamped on the tip you used yesterday. It is selected by looking at the coating, the surface, the desired production rate, the finish requirements, and the capacity of the sprayer.
Tip Selection Is Really Two Decisions
Choosing an airless tip requires selecting:
- appropriate for the coating.
- A fan width appropriate for the surface and the amount of control required.
The orifice determines how large the fluid passage is. The fan-width designation determines how broadly the coating is distributed.
Those two decisions work together, but they solve different problems.
Coating requirements help determine the orifice.
The size and shape of the surface help determine the fan width.
The sprayer must be capable of supporting both.
Step 1: Begin with the Coating
The coating manufacturer’s product data sheet should be the first place you look. Many product data sheets provide a recommended airless tip-orifice range, operating-pressure guidance, thinning instructions, and other application information.
A recommended range might allow several tip choices. That does not mean every tip within the range will produce identical results. It means the coating manufacturer has identified an orifice range generally suited to applying that material under the stated conditions.
Coating characteristics that can influence tip selection include:
- Viscosity
- Volume solids
- Required wet-film thickness
- Pigment and filler content
- Particle or aggregate size
- Shear sensitivity
- Application temperature
- Whether the material may be thinned
- Required finish quality
A thin stain does not behave like an elastomeric roof coating. A fine-finish enamel does not move through equipment like block filler. Asking one tip to handle all of them is like asking one wrench to fit every fastener in the building.
General Orifice Ranges
The following ranges are broad educational examples—not universal specifications. Coating formulations vary considerably, even among products with similar names. Always verify the correct range in the coating manufacturer’s current product data and the tip manufacturer’s selection guide.
| General Material Type | Illustrative Orifice Range | Selection Considerations |
|---|---|---|
| Light stains and thin clear materials | Approximately 0.009–0.013 inch | Fine control, low material delivery, and finish quality may be priorities. |
| Lacquers, varnishes, and light enamels | Approximately 0.011–0.015 inch | , solids content, and desired finish can shift the appropriate size. |
| Primers and architectural coatings | Approximately 0.015–0.021 inch | Product formulation and production requirements vary widely. |
| Industrial and protective coatings | Approximately 0.017–0.031 inch or larger | High solids, film-build requirements, pot life, and equipment capability matter. |
| Elastomerics, block fillers, mastics, and heavy coatings | Often 0.025 inch and larger | May require specialized pumps, larger passages, larger hoses, and manufacturer-approved components. |
Do not treat this table as permission to ignore the data sheet. “Latex paint” describes an enormous family of materials. One architectural coating may spray well through a 0.015-inch tip, while another may require a larger opening.
What Happens When the Orifice Is Too Small?
A tip orifice that is too small for the coating may:
- Restrict material delivery
- Slow production
- Require more passes to reach the specified film thickness
- Plug repeatedly
- Struggle to pass pigments, fillers, or larger particles
- Encourage the operator to use excessive pressure
- Produce an unsuitable or incomplete spray pattern
Installing a smaller tip does not automatically produce a finer finish. If the coating cannot pass through and atomize correctly, the result may be worse rather than better.
What Happens When the Orifice Is Too Large?
A tip orifice that is too large may:
- Deliver more coating than the operator can control
- Produce runs and sags
- Create excessive wet-film thickness
- Increase coating consumption
- Overload a sprayer with insufficient capacity
- Reduce the operator’s ability to work on narrow or detailed surfaces
- Create excessive overspray or bounce-back under some conditions
A larger hole is not free production. The coating still has to land in the correct place at the correct film thickness.
The objective is not to move the most paint possible. The objective is to apply the correct amount of coating, at the required film thickness, with acceptable control and finish quality.
Step 2: Match the Fan Width to the Surface
After identifying an appropriate orifice range, consider the size and shape of the surface.
A broad wall, roof, tank exterior, or large structural panel may benefit from a wider pattern. A railing, column, door frame, narrow beam, or small fabricated component usually requires more control.
| Surface | Fan-Width Consideration | Reason |
|---|---|---|
| Large wall or broad panel | Wider fan may improve production | Covers more surface with each properly overlapped pass |
| Door, cabinet side, or medium panel | pattern offers a balance of production and control | Helps keep the pattern on the workpiece |
| Railing, frame, pipe, or narrow beam | Narrower fan generally provides better control | Reduces the amount of coating sprayed past the edges |
| Detailed or irregular fabrication | Narrower, more controllable pattern may be preferred | Helps the operator address corners and changing geometry |
Selecting a 12-inch fan for a 4-inch rail does not make the work faster. Much of the pattern misses the target. The production number may look impressive at the tip while the coating-cost number tells a different story.
Same Orifice—Different Fan Width
Consider a 315 and a 515 tip:
- The 315 has an approximate 6-inch nominal fan and a 0.015-inch nominal orifice.
- The 515 has an approximate 10-inch nominal fan and the same 0.015-inch nominal orifice.
Under comparable conditions, both tips share the same nominal orifice size, but the 315 concentrates the material into a narrower pattern. The 515 distributes it across a broader pattern.
The narrower fan may provide better control on smaller work, but it can also deposit more material over a smaller area if travel speed and other conditions remain unchanged. Fan width changes how the material is distributed, so technique and film-thickness checks still matter.
Same Fan Width—Different Orifice
Now compare a 513, 515, and 517:
- Each has an approximate 10-inch nominal fan.
- Their nominal orifices are 0.013, 0.015, and 0.017 inch.
The fan-width designation remains the same, but the larger openings can deliver progressively more material at comparable pressure and fluid conditions.
The change from 0.015 to 0.017 inch may look small on paper. At the tip, it can represent a meaningful increase in material flow. Small changes in diameter create larger changes in opening area.
Step 3: Confirm Sprayer Capacity
Every airless sprayer has a maximum recommended tip size. The selected tip must remain within that limit.
A sprayer rated for a maximum 0.017-inch tip should not be expected to support a 0.021-inch tip simply because the tip fits the guard. The larger orifice demands more material than the pump was designed to deliver.
When tip demand exceeds pump capacity, the system may:
- Lose pressure while the gun is triggered
- Produce spray-pattern tails
- Pulse or surge
- Run continuously without maintaining the selected pressure
- Produce inconsistent material delivery
- Wear prematurely from excessive demand
Maximum tip ratings may decrease when two or more guns operate from one sprayer. The combined flow demand of all installed tips must remain within the pump’s capacity.
New Pump Capacity Versus Worn Pump Capacity
The published maximum tip rating generally describes equipment in proper operating condition. A pump with worn packings, valves, balls, seats, or other fluid-section components may no longer support the tip size it handled when new.
If a previously successful setup begins losing pressure, do not immediately assume that the original tip selection was wrong. Check tip wear, filters, inlet conditions, coating condition, hose arrangement, and pump performance.
Step 4: Consider the Required Film Thickness
A tip must help the operator achieve the specified wet-film thickness without moving so slowly that runs develop or so quickly that coverage becomes inconsistent.
High-build coatings may require greater material delivery, but film thickness should still be verified. A larger tip can help deliver material, but it cannot tell the operator how much coating actually remains on the surface.
Use a wet-film thickness gauge when appropriate and compare the result with the coating manufacturer’s requirement. Visual appearance alone is not a reliable film-thickness measurement.
Step 5: Consider Finish Quality
The largest tip that the coating and sprayer can tolerate is not always the tip that produces the desired result.
Finish-sensitive applications may benefit from:
- A more controlled material-delivery rate
- A fan width that fits the part closely
- A tip specifically designed for fine finishing
- Lower-pressure tip technology where appropriate
- Careful filtration and coating preparation
- Consistent gun distance, angle, speed, and overlap
Standard airless spraying, low-pressure airless, fine-finish airless, and air-assisted airless are related but different approaches. Select the tip family designed for the spray technology and finish requirement.
Step 6: Check the Filtration
The tip must work with the filters and strainers in the system. A fine filter may help protect a smaller tip from debris, but a filter that is too fine for a heavy coating may restrict flow or plug repeatedly.
Filter recommendations vary according to the material, tip size, equipment, and manufacturer. Check the tip manufacturer’s guidance and the coating product data before changing filter mesh.
A Practical Tip-Selection Process
- Identify the exact coating being sprayed.
- Read its current product data sheet.
- Find the recommended airless orifice range.
- Determine the required wet- and dry-film thickness.
- Choose a fan width suited to the surface.
- Confirm that the sprayer supports the selected orifice.
- Confirm tip, guard, gun, filter, and system compatibility.
- Condition and strain the coating as directed.
- Install the tip after properly relieving system pressure.
- Begin with low pressure and increase only enough to produce an acceptable pattern.
- Apply a test pattern on an appropriate surface.
- Verify coverage and film thickness before beginning production.
Common Tip-Selection Mistakes
- Using the same tip for every coating: Similar-looking materials can have very different application requirements.
- Selecting from memory instead of reading the data sheet: The coating manufacturer’s recommendation is more useful than yesterday’s habit.
- Choosing the widest possible fan: A pattern wider than the workpiece sends coating past the target.
- Choosing the largest tip the sprayer can handle: Maximum capacity is a limit—not a recommendation for every job.
- Ignoring film thickness: Good hiding does not prove that the correct amount of coating was applied.
- Trying to fix an incorrect tip with pressure: Pressure cannot change the physical size of the tip opening.
- Judging a tip without considering wear: A worn tip delivers and distributes material differently from a new tip.
Before You Start Spraying
- Verify the coating manufacturer’s recommended tip range.
- Choose a fan width that keeps the pattern on the work.
- Confirm the sprayer’s maximum tip rating.
- Account for multiple guns if more than one will be used.
- Confirm that filtration is appropriate.
- Inspect the tip and guard for wear or damage.
- Test the pattern using the lowest pressure that produces acceptable atomization.
- Measure wet-film thickness where applicable.
Safety Notice: Tip Changes Require Pressure Relief
Airless spray equipment produces fluid pressure capable of penetrating skin and underlying tissue. Never place a hand, finger, glove, or rag in front of the spray tip. Never use your hand to check or stop a high-pressure leak.
Engage the trigger lock and follow the equipment manufacturer’s complete pressure-relief procedure before removing, reversing, cleaning, inspecting, or replacing the tip or guard. Switching off the sprayer does not necessarily relieve pressure trapped in the gun and hose.
Use only tips, guards, guns, hoses, fittings, and accessories compatible with the equipment and rated for its maximum working pressure.
A suspected injection injury is a medical emergency. Seek immediate emergency treatment. Do not treat the injury as an ordinary cut.
This article provides general educational information. Always follow the current instructions and warnings supplied by the equipment, tip, and coating manufacturers.
Check Your Understanding
- Which coating document should normally be consulted before selecting an airless tip?
- Which part of tip selection is primarily influenced by the coating: fan width or orifice size?
- Why might a narrow fan be preferred for a railing or narrow beam?
- What may happen if the selected tip exceeds the sprayer’s capacity?
- Why should wet-film thickness be checked after selecting a tip?
If you can explain why the right tip must fit the coating, the workpiece, and the sprayer, you understand the foundation of airless tip selection.
The Bottom Line
Choosing the correct airless tip is not a contest to find the largest opening or widest fan. It is a matching process.
Start with the coating manufacturer’s recommended orifice range. Select a fan width that fits the surface. Confirm that the sprayer can support the tip. Then test the pattern and verify that the required film thickness can be applied with control.
The right tip does not merely fit the gun. It fits the entire job.
Free to Learn. Earned Through Completion.
Finishing Starts With Understanding.
AirSprayTech.com
The Finishing Authority®
© 2026 Azimuth Spray Systems, LLC. All rights reserved.