Unmask the Secret to Perfectly Sprayed Wall Paint
When it comes to painting the walls in your home, spraying paint offers clear advantages over the traditional brush and roller method. Spraying delivers a smooth, professional-grade finish that simply can't be matched by manual brushwork. Let's look at some of the key benefits spray painting brings to any wall painting project.
Attain a Smooth, Seamless Finish
A spray gun applies paint in an ultra-fine mist that lays down a thin, even coat with each pass. This allows the paint to spread flawlessly across the surface, free of brush marks, stippling, or other imperfections. The resulting finish is remarkably smooth, seamless, and uniform. Areas that were previously marred by uneven paint coverage or touchups become virtually invisible.
Crisp Lines and Uniform Coverage
Spraying also enables you to achieve razor-sharp cut lines along trim and borders with less taping or edgework required. The precision of the spray fan pattern delivers paint exactly where you aim it, preventing bleed under tape lines. You can tackle intricate areas like crown molding without worrying about drips or uneven buildup of paint.
Speed and Efficiency
While spraying does require more prep work up front, the painting process itself is far faster than brushing or rolling. The wide spray pattern and fine mist of paint enables you to coat much more surface area in a single pass. Two light coats of spray paint can achieve the same coverage as three or four brushed coats, with a fraction of the time and effort.
Sprayer Types: HVLP vs. Airless
When selecting a paint sprayer for home wall painting projects, the two main options are high volume, low pressure (HVLP) spray guns and airless sprayers. Both can deliver excellent results, but they operate differently.
HVLP Spray Guns
How HVLP Sprayers Work
HVLP spray systems use compressed air to atomize paint and propel it onto surfaces. Paint is held in a stainless steel cup attached to the spray gun handle. An air cap atomizes the paint into a fine spray pattern. Adjustable controls alter the fan pattern width and material flow as needed.
HVLP Benefits and Drawbacks
HVLP spray guns are lightweight, highly maneuverable, and offer great control and paint atomization. They produce very little overspray and waste compared to airless models. However, they involve a longer setup process, require an air compressor, and have lower pressure output. This makes them better suited for interior wall painting instead of covering large exterior areas.
Airless Sprayers
How Airless Sprayers Work
Airless sprayers use an electric or gas-powered pump to pressurize paint, pushing it through a hose to the spray gun tip. This hydraulic pressure atomizes the paint, forcing it out in a wide, high pressure fan pattern. Spray pressure can reach over 3000 PSI.
Airless Sprayer Pros and Cons
Airless models offer extremely high paint output with less thinning required. Their high pressure allows them to spray unthinned paint over large exterior surfaces. However, all that power comes at a cost - airless sprayers are more prone to overspray and require more containment. They also represent a bigger up front investment than HVLP systems.
Preparing Walls for Paint Spraying
While spray painting may be faster, you'll need to spend more time preparing your workspace for the best results. Proper prep work ensures the paint adheres well and provides a uniform finish.
Filling Holes and Imperfections
Begin by washing walls to remove any dirt, oil or grease. Fill holes, cracks and other defects with spackle or joint compound, and sand smooth once dry. Dust walls thoroughly after sanding to remove any residual debris.
Sanding Glossy Surfaces
If walls were previously painted with a glossy paint, sand them lightly to dull the sheen before respraying. This "keys" the surface so the new paint can grip evenly across the entire area.
Cleaning and Removing Grease
Use TSP (trisodium phosphate) or other cleaning solutions to remove any lingering grease, smoke residue or stains. Rinse thoroughly and allow walls to fully dry before beginning any painting. Address persistent stains with primer or sealers made to block them.
Applying Primer and Sealer
On new drywall or freshly skim coated walls, apply a coat of quality drywall primer before painting. For heavily stained existing walls, use a stain-blocking primer like Kilz. These create a fresh uniform base for the new paint.
Masking and Taping Techniques
While overspray from HVLP spray guns is minimal, you'll still need to take some protective steps to shield floors, trim and furnishings from stray paint mist.
Protecting Floors and Furnishings
Clear the room as thoroughly as possible, including removing wall hangings. Cover floors with plastic sheeting, securing edges with painter's tape. Drape lightweight drop cloths over any remaining furniture or fixtures.
Taping Trims and Crown Molding
Apply painter's tape along the edges where walls meet ceilings, baseboards, trims and moldings. Press it down firmly to prevent bleed under the tape lines. For intricate trim and molding, tape off just the wall area 1-2 inches from the trim to avoid build up.
Masking Off Windows and Doors
Fully mask windows by taping plastic sheeting over the glass to prevent overspray from entering between panes. Likewise, seal exterior doorways with tape and plastic to keep spray mist from drifting outside. Exterior surfaces will also need masking.
Setting Up Your Equipment
Once prep work is complete, it's time to assemble your HVLP spray setup - a task made much easier if you understand each component and connection.
Assembling the Spray Gun
Attach the paint cup, pickup tube and tip guard according to manufacturer directions. Tighten fittings securely but carefully to prevent cracking. Select and install the proper needle/nozzle for the paint type and tip size for the spray pattern needed.
Attaching Hoses and Filters
Connect one hose from the air compressor to the gun's air inlet fitting. Attach a second hose to siphon paint up from the cup. Install inline paint filters to catch debris that could clog the spray tip. Place a regulator at the compressor outlet to control air pressure.
Filling the Paint Cup
Pour pre-thinned latex wall paint into the stainless steel cup, leaving room at the top for airflow. Larger projects may require a paint feed system with a remote cup or direct siphon from paint cans. Make sure pickup tubes reach to cup bottom.
Adjusting Paint Viscosity
Proper paint thinning is imperative for smooth spray results. Follow viscosity guidelines to balance good atomization with sufficient film build.
Determining Ideal Paint Thickness
Check manufacturer thinning recommendations listed on tech sheets or cans. For latex wall paints, a viscosity of 20-30 seconds on a Ford #4 viscosity cup at 70degF is a good target range.
Adding Paint Thinner as Needed
If paint exceeds the ideal viscosity range, thin in small increments with water (latex) or mineral spirits (oil-based) per guidelines. Stir thoroughly and recheck. Thin carefully to avoid over-thinning.
Best Practices for Spray Technique
With prep work and spray equipment now complete, focus on honing techniques for the smoothest possible paint application.
Maintaining Proper Distance
Position the spray tip 6 to 12 inches from the wall surface. Get a feel for the ideal distance based on sprayer power and paint consistency. Move arm across sections steadily rather than wrist only.
Using Correct Nozzle Type
An HVLP paint sprayer equipped with the right nozzle can produce different shaped spray patterns. Use flat spray tips for broad wall expanses. Change to round spray tips for cutting in narrow spaces.
Employing Proper Motion and Pace
Move deliberately, with the spray overlapping the previous pass by 30-50% for uniform coverage. Work methodically section to section. Avoid angling the spray pattern along edges.
Achieving Full Coverage in Each Pass
Feather out spray at the end of each pass rather than shutting off abruptly. Each stroke should leave a wet edge to blend into adjacent sections. Overlap effectively to prevent holidays, bare areas or thin spots.
Avoiding Common Problems
Be alert during the spray process to nip any application issues in the bud before the paint dries.
Preventing Runs and Sags
Apply light coats, allowing proper dry time between passes. Avoid holding the spray gun too close or concentrating spray in one area to prevent drips.
Fixing Orange Peel Texture
If paint dries too quickly, it can develop an uneven orange peel appearance. This occurs due to improper thinning, spraying too far away, or building up coats too rapidly. Prevent this by slowing pace and thinning properly.
Minimizing Overspray Issues
Ensure adequate masking to reduce stray paint mist. Spray test panels first to set distance and pattern size. Clean overspray immediately from any exposed areas before it dries using mineral spirits.
Cleanup and Equipment Care
Completing painting is only half the job - you'll also need to thoroughly clean your HVLP spray equipment and store it properly between uses.
Cleaning the Spray Gun Thoroughly
Follow manufacturer cleaning steps closely to prevent paint from drying inside the spray gun. Flush all paint passages multiple times to remove residue. Disassemble parts to clean fully. Use paint thinner suited to the paint type.
Storing Equipment Properly
After cleaning spray guns, prevent corrosion by lightly oiling any exposed metal parts. Replace tip guards and store upright to avoid straining internal seals. Drain and cap hoses, coiling neatly to prevent kinks.
You can achieve stunning, professional-grade results spraying interior wall paint with the right spray equipment. Your patience in taping off surfaces and adjusting paint flow will pay off in smooth, uniform coverage free of drips or brush marks. Follow these best practices and you'll never want to pick up a roller and paint tray again!