How do I know what size Spray Tip to use?

Why spray tip size matters

Your spray tip controls two big things: how much coating leaves the gun and how wide the fan is. The right match helps you get a more consistent finish and reduce wasted paint and rework.

Tip selection – understanding the numbers

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.

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.

A practical way to choose your tip

1) Match the orifice to the coating

Use a smaller orifice for lighter coatings (lacquers, stains, enamels) and a larger orifice for heavier coatings (texture, block filler, elastomerics). Many paint manufacturers list recommended tip sizes on the tin or the product data sheet.

2) Match the tip to your sprayer’s rating

Confirm your sprayer can handle the tip you want (and the multiple-gun rating if you run more than one gun).

3) Match the fan to the size of the surface

Broad surfaces usually suit a wider fan. Narrow, detailed areas usually suit a narrower fan for control and less overspray. (Tip fan ratings assume about 12 inch spray distance.)

Tip sizes that we suggest for each job

Job	Common coating type	Start with these tip sizes
Interior walls	Water-based wall paint	413,415,417,419,515,517,519
Ceilings	Flat Water-based	515
Exterior cladding, weatherboards	Exterior Water-Based	413,415,417,419
Fences (pickets, rails)	Stain or exterior paint	413,415,417,419
Roofs (typical acrylic roof paint)	Heavy Water-based	413,415,417,419,515,517,519
Roofs (elastomeric or very heavy coatings)	Elastomeric	419,519,525
Architraves, trim, doors (fine finish)	Enamel or fine finish products	210 to 310
Cabinets and joinery (fine finish)	Lacquer, enamel	208 to 212, 308 to 312

Quick Checklist before you spray

Confirm the paint’s recommended tip range on the tin or product data sheet.
Confirm your sprayer’s max tip size rating.
Pick the fan width that matches the surface size, then pick the orifice that matches the coating.
Use the right gun filter mesh for the tip size and coating type.
Start with lower pressure and increase only until the pattern cleans up.